tag:blogger.com,1999:blog-12909234081095460492024-03-05T03:52:45.194-05:00A Star Close Up"The book said something astonishing, a very big thought.<br>It said that the stars were suns, only very far away.<br>The Sun was a star, but close up."—Carl Sagan, <i>Cosmos</i>, 1980The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.comBlogger41125tag:blogger.com,1999:blog-1290923408109546049.post-83755858487360728782022-04-08T20:24:00.002-04:002023-04-24T19:16:59.961-04:00Dawe 3001A Frequency Counter<div><p>Behold the Dawe 3001A Frequency Counter. It was an eBay steal. No one else even bid on it. </p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg5rtofY7d6mTcZl1r4tlCxcTrLUOZ5DMpaJ20VqS5vMU0nUP_SPNdn3-k-Ngu-jRhpzJkaTX_gWQLVBbni1KVgvAYdPIeiKgQqm5XWC1FyJdF68HJYLkUuICrNDlq1prT62MobEQ0iFMfI9G0ZCp5bTANWPTt3-NiQMo-Ev6ftpWlL4g794ejTtG4w/s1157/Dawe%20Frequency%20Counter.jpg" style="margin-left: 1em; margin-right: 1em;"><img alt="On The Bench" border="0" data-original-height="672" data-original-width="1157" height="233" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg5rtofY7d6mTcZl1r4tlCxcTrLUOZ5DMpaJ20VqS5vMU0nUP_SPNdn3-k-Ngu-jRhpzJkaTX_gWQLVBbni1KVgvAYdPIeiKgQqm5XWC1FyJdF68HJYLkUuICrNDlq1prT62MobEQ0iFMfI9G0ZCp5bTANWPTt3-NiQMo-Ev6ftpWlL4g794ejTtG4w/w400-h233/Dawe%20Frequency%20Counter.jpg" title="On The Bench" width="400" /></a></div><p></p><p style="text-align: center;"><span style="font-size: x-small;">Click to Enlarge</span><br /></p><p><br /></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj_TAlgQLzrN-V8nwZSd-bCT7JtaQs0Yd7J_dgBdxhlvuGVrOAVoKzJjqDSdRsFczW2dapjF1FXu9z93-Nz6OTRvCInDowEPDIeeBU5c2yAJMKtkGKSgoS2rg8XZNMWZM9vVaHmI6oyB2vn_G2FqQbbNj1f2FpqTIo4RlZaNczW0gi3j2L_T8QPsee0/s971/Dawe%203001A%20Frequency%20Counter%20-%20eBay.jpg" style="margin-left: 1em; margin-right: 1em;"><img alt="Ebay Photo" border="0" data-original-height="679" data-original-width="971" height="280" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj_TAlgQLzrN-V8nwZSd-bCT7JtaQs0Yd7J_dgBdxhlvuGVrOAVoKzJjqDSdRsFczW2dapjF1FXu9z93-Nz6OTRvCInDowEPDIeeBU5c2yAJMKtkGKSgoS2rg8XZNMWZM9vVaHmI6oyB2vn_G2FqQbbNj1f2FpqTIo4RlZaNczW0gi3j2L_T8QPsee0/w400-h280/Dawe%203001A%20Frequency%20Counter%20-%20eBay.jpg" title="Ebay Photo" width="400" /></a></div><br /></div><div style="text-align: center;"><span style="font-size: x-small;">Click to Enlarge</span><br /></div><p style="text-align: left;">The counter consists of two separate units. The top is a fully self-contained counter module which attaches to the "front end" on the bottom via a short cable with what look like DIN-5 connectors.<br /></p><p style="text-align: left;">It's hard to believe that three years have gone by since I took the first photo. The Nixie® tube on the left displays zero and two whenever it's supposed to be zero or two. There may be an internal short in the tube itself. I need to check that three years from now. ⏰<br /></p>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-9286155246950478402019-09-10T17:31:00.000-04:002022-04-09T16:56:49.605-04:002015 iMac Display ReplacedThe new display is here and working just fine but I was in for a big surprise when I took the cracked one off. The adhesive had "set up". The display was now firmly attached to the case! I had to use the pizza cutter tool again to take it back off. 😮<br />
<br />
I'm out $446. OTOH, I'm going to upgrade to a 2019 and a close friend has offered me more significantly than the current eBay value for this 2015 so I'll break even.<br />
<br />
Sure would like to have that $446, though. 💸The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-18852198403763266242019-06-19T21:04:00.003-04:002022-04-09T16:57:04.348-04:002015 iMac DisasterWell gang, it wasn't long before the <a href="https://www.astarcloseup.com/2019/05/2015-imac-teardown-and-second-ssd.html" target="_blank">repair/upgrade of my 27" 2015 iMac</a> came to grief. I got up, walked in the room and there before me was a computer with its display lying on the edge of beloved Herman Miller Ferrari-colored computer chair. I was so horrified that I didn't even think to take a picture of that appalling tableau. No, no one else will ever have the sadly-missed golden opportunity to co-experience such an exquisite non-rush. <br />
<br />
I stood there in a daze for some time. Reality itself was beyond my capacity to entertain. <span style="font-size: large;">😑</span><br />
<br />
I finally came out of my stupor. As I gingerly lifted the display up and turned it over I beheld cracks aplenty:<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhBlII6BmhXE0jFFKjbUg-hmmIrpewLHAi9TJJgbmq939mCtZDFl3mB8zLnMQO3M4Y_VpZ9mYwzCRnxeRpHs6Lfxx5WC_k-WxgUHbEZBlrbjUnzEkep69BDgph_dXXgb2DSpvQguSX5f1w/s1600/Cracks-1.1.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="355" data-original-width="676" height="168" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhBlII6BmhXE0jFFKjbUg-hmmIrpewLHAi9TJJgbmq939mCtZDFl3mB8zLnMQO3M4Y_VpZ9mYwzCRnxeRpHs6Lfxx5WC_k-WxgUHbEZBlrbjUnzEkep69BDgph_dXXgb2DSpvQguSX5f1w/s320/Cracks-1.1.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Full screen (click to enlarge)</td></tr>
</tbody></table>
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj11uSSBNhQ243i98aKH40S7wGv864-6MOGWUB7FJ1kfi_ozKguPLVRatbDFq8hyphenhyphenlrtKlGa5IA8FOAwKisSn9Xre4QHf6W7UKzvKlYr_5KKIR0wr6m4eE03EI1uE510QIAEkKGOvW6RR9g/s1600/Cracks-enhanced.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1169" data-original-width="1279" height="292" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj11uSSBNhQ243i98aKH40S7wGv864-6MOGWUB7FJ1kfi_ozKguPLVRatbDFq8hyphenhyphenlrtKlGa5IA8FOAwKisSn9Xre4QHf6W7UKzvKlYr_5KKIR0wr6m4eE03EI1uE510QIAEkKGOvW6RR9g/s320/Cracks-enhanced.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Right end</td></tr>
</tbody></table>
<br />
Needless to say the video and back-light cables were no longer in their
sockets on the logic board. Having worked on aluminum iMacs numerous
times I immediately assumed the worst. That is, all surface-mount
connectors ripped clean off the PC board. Amazingly, the backlight connector had no damage at all. The embedded DisplayPort (eDP) connector only had its ends bent.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiMJDNZXjr4wgBIzLuHal-l2ibZqYszCStSoFTj9_AUsoH_ECyj9BDNWrI4A5TqAzuVymateWb7iHcltEx2nlrgabY1p8NTuL9ypw3XFWQWdxM60Gw2WLRMtlqyzgpbGJU9wqIUsZTifaE/s1600/Backlight-connector.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="346" data-original-width="598" height="185" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiMJDNZXjr4wgBIzLuHal-l2ibZqYszCStSoFTj9_AUsoH_ECyj9BDNWrI4A5TqAzuVymateWb7iHcltEx2nlrgabY1p8NTuL9ypw3XFWQWdxM60Gw2WLRMtlqyzgpbGJU9wqIUsZTifaE/s320/Backlight-connector.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Backlight connector</td></tr>
</tbody></table>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiPHVkyyhchnD4C9YNaYEDVnVt0t0f1h-BdyxFAypZzTAN4MaxqudinjqcpmfPjw05UB-xH5raptojTtnYaXoKmFVDEap2mJHuaIbc8fzyV3X62R5YYLZxQMZWYtXT7zJJv-rGwHQPCw4Q/s1600/Video-connector.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="280" data-original-width="592" height="151" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiPHVkyyhchnD4C9YNaYEDVnVt0t0f1h-BdyxFAypZzTAN4MaxqudinjqcpmfPjw05UB-xH5raptojTtnYaXoKmFVDEap2mJHuaIbc8fzyV3X62R5YYLZxQMZWYtXT7zJJv-rGwHQPCw4Q/s320/Video-connector.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">eDP connector</td></tr>
</tbody></table>
There was virtually <b>no</b> adhesive residue on the back of the display except along the bottom which was still quite tacky and one small spot about an inch wide elsewhere. The frame was also tacky but not as much as it should have been.<br />
<br />
We wiped everything down with IPA before we put the new adhesive strips on. Perhaps we rubbed the strips too hard while we were putting them on the case. I'm sure this is a pressure-sensitive adhesive so that may have made it start to cure before we got the display on. OTOH, we may not have rubbed things together as tightly as we should have <i>after</i> the display was on. At this point I don't know what to think.<br />
<br />
Better pictures to come when we take it apart again to replace the display. <span style="font-size: large;">😷</span><br />
<br />
<span style="font-size: small;">Thank "Bob" it didn't reach the floo</span><span style="font-size: large;"><span style="font-size: small;">r. At least it's still working.</span></span><br />
<br />
<div style="text-align: center;">
<span style="font-size: large;">🖥</span></div>
The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-3965495414064686182019-06-13T17:20:00.000-04:002022-04-09T17:00:06.712-04:00Eldorado 325A Frequency CounterMy latest acquisition from eBay:<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgpUn-2OackTSK005Ymux_aZzUPf-oiDFoWRBcrFoqWxiLsMXhRkUuLnBRCaIeXLwV6UmuUlMvHwvF5mCYWfDMMpvkbX3oqA1jLPt7cMSFtDGcKf5xgkqKMXZpBlVvi4XwBMVYiRxsuQQY/s1600/Meter.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="759" data-original-width="827" height="293" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgpUn-2OackTSK005Ymux_aZzUPf-oiDFoWRBcrFoqWxiLsMXhRkUuLnBRCaIeXLwV6UmuUlMvHwvF5mCYWfDMMpvkbX3oqA1jLPt7cMSFtDGcKf5xgkqKMXZpBlVvi4XwBMVYiRxsuQQY/s320/Meter.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">From the seller's photo (heavily retouched by me)</td></tr>
</tbody></table>
Works perfectly down to 1Hz. I haven't tested the high end yet. I had a shoot all set up but as usual a disaster cropped elsewhere. I'll update this post with more pictures later if I have the chance.<br />
<br />
$67. I was the only bidder.<br />
<br />
The next day a model 224 with only four settings went for $65. <span style="font-size: large;">🙄</span>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com4tag:blogger.com,1999:blog-1290923408109546049.post-40078136454486597822019-06-07T17:26:00.004-04:002022-04-09T17:01:39.504-04:00Systron Donner 6052 Frequency Counter<i>This is a work in progress...</i><br />
<br />
Here is an HDR image:<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgve2hPo4y4g2PW3Im1ngSqj6_a4-QhEpRJ_K2_2dJiiTeUWBJSq8edh5DKXVPBMQICwZdu6DVxtFYQhHpwyuTr1QekCKoo2_dDDpTIgqJxsn41Hq-iz3CdShKzPYWKCNbjS9qf_1iJalk/s1600/SD-6052.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="636" data-original-width="954" height="213" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgve2hPo4y4g2PW3Im1ngSqj6_a4-QhEpRJ_K2_2dJiiTeUWBJSq8edh5DKXVPBMQICwZdu6DVxtFYQhHpwyuTr1QekCKoo2_dDDpTIgqJxsn41Hq-iz3CdShKzPYWKCNbjS9qf_1iJalk/s320/SD-6052.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table>
<span style="font-size: small;"><span style="font-family: inherit;">The least-significant digit is working properly. The long exposure time captured it bouncing between zero and one. Note how the HDR processing has exaggerated every speck of rust and dirt around the knob. Live and in person it looks less grubby.</span></span><br />
<span style="font-size: small;"><br /></span>
<span style="font-size: small;">I just realized that this unit has nine decades, not eight. Excellent for a portable, desktop frequency counter.</span><br />
<span style="font-size: small;"><br /></span>
<br />
<div style="text-align: center;">
<span style="font-family: inherit;"><span style="color: #b4a7d6;"><span style="font-size: large;">☀</span></span></span></div>
The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-30323239641992692052019-05-31T18:42:00.004-04:002022-04-09T17:10:44.382-04:00Systron Donner 8350 Timecode Reader/GeneratorHere's a lousy shot of my Nixie tube timecode generator/reader:<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjuLvgIkYwLAwkzSH0F1v1szZpCsgAmGLYailji9xiksMCnhv0jOOjxnr9h9uCRmFBknqDJ8xzh8GlKcj1TOnil1PjoNK7oi3UqDWSC1oeqj2fEd1BIuUbeAfwducYSErjZ0aUcuvQBR7g/s1600/IMG_9086.jpg" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="330" data-original-width="1600" height="80" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjuLvgIkYwLAwkzSH0F1v1szZpCsgAmGLYailji9xiksMCnhv0jOOjxnr9h9uCRmFBknqDJ8xzh8GlKcj1TOnil1PjoNK7oi3UqDWSC1oeqj2fEd1BIuUbeAfwducYSErjZ0aUcuvQBR7g/s400/IMG_9086.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click for a <i>much</i> better view!</td></tr>
</tbody></table><p>
I'm not sure what tubes are in it but the envelopes are only about 2" high. The thumbwheels set the starting time for generator mode so it can be used as a Nixie clock. The entire case is only one unit high.<br />
<br />
Note the two missing keycaps between "Hold" and "Power". The plastic has become so brittle that the ears snapped like twigs with I pulled them off to replace the light bulbs. Not only does it look stupid but without the caps in place the switches can't be actuated.<br />
<br />
I saved the pieces. I suppose they could be glued back together with a thin, springy piece of steel reinforcing the joint and making it flexible enough for them to be put back on again.<br />
<br />
If I had new, blank caps I could reproduce the text with decals. If anyone has a fix please message me.<br />
<br />
Perhaps later I'll have time to take a better picture and get some interior shots. And get the part numbers on the tubes.</p><p>9/12/2020: I just noticed that the lens cap is sitting on top of it. 👁<br /></p>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com4tag:blogger.com,1999:blog-1290923408109546049.post-80211399828833066492019-05-30T20:24:00.000-04:002022-04-09T17:13:41.860-04:002015 iMac Teardown and Second SSD InstallationA few months ago my iMac 17,1 made some <i>very</i> scary noises. It sounded like a loose plug in an AC socket arcing away accompanied by some hissing. There was no magic smoke, no smell.<br />
<br />
Last week we tore the machine all the way down to inspect it. The power supply had no visible damage or odor. The AC socket and wires were OK. The mystery remains a mystery.<br />
<br />
While we had it open I installed a second SSD in the HDD bay. Because the machine shipped with an Apple SSD on the logic board and no hard drive in the HDD bay I didn't know if the mounting brackets were installed. I found conflicting reports online. What I knew for certain was that the SATA cable to the HDD bay was not installed so I purchased a new one.<br />
<br />
I also purchased an SSD installation kit from <a href="https://eshop.macsales.com/item/OWC/K27IM12HE1TB/" target="_blank">OWC</a> which included a 1TB SSD, 3.5" to 2.5" adapter, "pizza cutter" tool for detaching the display (which is glued on), a thermal sensor and the adhesive tapes for re-attaching the display.<br />
<br />
I got lucky—the drive brackets were there along with a lot of dust:<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjUea1Brp49oMOLAV1hm1h6KM_E1pozBHNkE8pGvvIDoaNFWwnYgphoegAyZ3vOwRfoD_TXOwNVxOMsqD8sRxNb9CI6OtlCeIpj9W2bPn5pWbflf3kT0YuFtxoXKONWvR5BFi8NUYs0bEg/s1600/Brackets.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="" border="0" data-original-height="582" data-original-width="755" height="308" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjUea1Brp49oMOLAV1hm1h6KM_E1pozBHNkE8pGvvIDoaNFWwnYgphoegAyZ3vOwRfoD_TXOwNVxOMsqD8sRxNb9CI6OtlCeIpj9W2bPn5pWbflf3kT0YuFtxoXKONWvR5BFi8NUYs0bEg/s400/Brackets.jpg" title="Drive Brackets" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Thank you Apple</td></tr>
</tbody></table>
The only thing I didn't have were the pin-shaped screws that go into the grommets on the HDD brackets. We managed to fasten the drive adapter in place with some regular drive screws. They fitted snugly in the grommets and it's very unlikely that any of them will vibrate loose.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjZQMYO-VPB4jkDIgXkH8rUuFqwJ3gBtiNZ1pRIpi5MOM2nMnaOXf2REti20bJ_v8t6nb8fT4_DxDQF2ZolJXqgFPCdLe07Sp0YO9CpbIB8cXZjZDlAGg-t9WXz3yyfqD74iIZBQJubHZw/s1600/Finished.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="" border="0" data-original-height="582" data-original-width="918" height="252" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjZQMYO-VPB4jkDIgXkH8rUuFqwJ3gBtiNZ1pRIpi5MOM2nMnaOXf2REti20bJ_v8t6nb8fT4_DxDQF2ZolJXqgFPCdLe07Sp0YO9CpbIB8cXZjZDlAGg-t9WXz3yyfqD74iIZBQJubHZw/s400/Finished.jpg" title="Installation Complete" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">New SSD in place</td></tr>
</tbody></table>
(Note that I installed a 500GB Samsung EVO 850 that I already had on
hand. I'm saving the OWC 1TB SSD from the kit for an external
enclosure.)<br />
<br />
There was one heart-stopping moment when the display slipped out of our hands and the bottom landed about 1/16" above the lower edge of the housing. We very carefully pulled it loose without breaking the glass and put it back in place correctly.<br />
<br />
I held my breath again as I pushed the power button. The machine chimed, the fan spun up, and the display came on. What a tremendous relief. I spent <i>weeks</i> researching every aspect of the project and in the end it paid off.<br />
<br />
Next up—install Mojave on the second internal SSD and find out how much of the software I use on a regular basis in El Capitan is broken. I'm going to buy a 2019 iMac as soon as refurbs start turning up in the Apple Refurbished Products store. Then next generation iMac will require macOS 10.15 Catalina (or later) which will no longer support any 32 bit software so a 2019 could be my last Mac purchase for a long time. No new Mac Pro and 6K Retina display for me even if I could afford them. <br />
<br />
So that's my story. I've used it for months since the scary incident with lots of heavy gaming sessions cranking the cores and the GPU up to the max without any problems. Fingers crossed.<br />
<br />
<div class="separator" style="clear: both; text-align: left;">
Finally, <i>I could never have done all this by myself!</i> I can't thank my buddy <b>Bogart</b> enough for his help.</div>
The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-4636449315066706372018-07-28T21:12:00.000-04:002020-04-10T12:31:58.548-04:00Scintillation Probe Kit<b>Prologue:</b> <i>A New Geiger Counter...</i><br />
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With the arrival of a new Geiger counter with a x1000 scale it was finally time to assemble the scintillation probe kit I purchased from <a href="http://stores.ebay.com/The-Rad-Lab">Iradinc</a> in 2014. The probe only required 900V so the stage was set.<br />
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The first hassle was to clear off enough space on my decrepit workbench.<br />
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<b>The Kit</b><i><b>:</b> Some Assembly Required...</i><br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgol3V8YQnOF1jlfjBxGBdWZNgcIpl4UyoLbiZk3UhPiqL0tFlYUpn5wB1JlZ7AaxqmrW5izYh95xwAJJlyV7MTDwcVnEMAq9UbRZ-R7V3cv-_ULZNxV2sDxGg3MRlxXVoteBtpQydaOYs/s1600/Parts.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="854" data-original-width="1090" height="313" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgol3V8YQnOF1jlfjBxGBdWZNgcIpl4UyoLbiZk3UhPiqL0tFlYUpn5wB1JlZ7AaxqmrW5izYh95xwAJJlyV7MTDwcVnEMAq9UbRZ-R7V3cv-_ULZNxV2sDxGg3MRlxXVoteBtpQydaOYs/s400/Parts.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">The pieces of the puzzle (<i>click to enlarge</i>)</td></tr>
</tbody></table>
Left to right: 3" diameter 2.25" plastic crystal; Hamamatsu R6233 Photomultiplier tube; tube cap; BNC connector; voltage divider parts; silicone grease; huge diameter heat shrink tubing.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgaZ2AhhTUviZATgEqb9IDyEVeZHdZ267KxOVScd02-Bv0rA7QLOdEl6GmhdbKW6W4vDB77fnjIiLxMO28IRjuxPp_J8qD8ra97xqPiiqOqacD4ywaqyKijerWAUOjbXkWxCNEaUom6Ie4/s1600/Supplies.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="976" data-original-width="844" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgaZ2AhhTUviZATgEqb9IDyEVeZHdZ267KxOVScd02-Bv0rA7QLOdEl6GmhdbKW6W4vDB77fnjIiLxMO28IRjuxPp_J8qD8ra97xqPiiqOqacD4ywaqyKijerWAUOjbXkWxCNEaUom6Ie4/s400/Supplies.jpg" width="345" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Additional materials (<i>click to enlarge</i>)</td></tr>
</tbody></table>
Isopropyl alcohol, spray adhesive, electrical tape — all as recommended by the <a href="https://groups.io/g/GeigerCounters">GeigherCounters group</a> brain-trust. I still haven't found any 99% isopropyl alcohol locally but I did get some 90%...<br />
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The first step was to wire up the resistor string on the base of the PMT. My eyesight has been going downhill for years and this was somewhat of a challenge. The markings on the tiny resistors were very hard to make out. I was very nervous about plunging in and naturally I managed to scratch the insulation off of one. Tom was kind enough to send me some spares so I dodged that bullet. <br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhnxpIaWY2G_EXWrlelX3CkPXqqTC_SEwu2OV727lR0OvngGQTF2kB-CB-Px47Purz61OfUmFmNBxXXLVUEXL31bpVH8obPiazuj3yd04POhfuVgAvUWIgRmICpoyvXQ_lUc8GcEqjRzG4/s1600/Resistors.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1002" data-original-width="1160" height="345" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhnxpIaWY2G_EXWrlelX3CkPXqqTC_SEwu2OV727lR0OvngGQTF2kB-CB-Px47Purz61OfUmFmNBxXXLVUEXL31bpVH8obPiazuj3yd04POhfuVgAvUWIgRmICpoyvXQ_lUc8GcEqjRzG4/s400/Resistors.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">PMT voltage divider complete (<i>click to enlarge</i>)</td></tr>
</tbody></table>
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgsRYPwdyQr0JXdy7vR_xOE5w26yMgiK_dX8wxiF51BO3jW7grfMIOLFtWon1yIQSuRQGqiHZvmYXe6dXz-RT8OwsXqq7htGcKxDrBrA-rRoWoy9tyUeNMk1GWvNMUTALnS13ACzquEoBg/s1600/BNC-in-cap.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="722" data-original-width="936" height="307" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgsRYPwdyQr0JXdy7vR_xOE5w26yMgiK_dX8wxiF51BO3jW7grfMIOLFtWon1yIQSuRQGqiHZvmYXe6dXz-RT8OwsXqq7htGcKxDrBrA-rRoWoy9tyUeNMk1GWvNMUTALnS13ACzquEoBg/s400/BNC-in-cap.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">BNC connector attached (<i>click to enlarge</i>)<br />
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</tbody></table>
At this point it was time to glue the cap to the PMT. Unfortunately, the silicone rubber I had bought turned out to be the type that gives off acetic acid while curing. This damages electronic components.<br />
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I had specifically searched for and bought what I thought was "neutral cure" but somehow managed to screw that up. Yet another delay as I waited for the correct adhesive to arrive (once again I couldn't find any locally).<br />
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<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiBkRZcU6aRYsdqb8HhVbfFIAXfidssphtF50Kn2n5t6DENJNM_3dnUvhkxegiLLEf-eRzRgTbe4iq-_FbrKUmnVm-oNITPLf9Q1yPefECqNN9HUcYk0ri6Ksen4MO5mu7gy7QO3iuuuxo/s1600/PMT-%2526-crystal.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="509" data-original-width="969" height="210" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiBkRZcU6aRYsdqb8HhVbfFIAXfidssphtF50Kn2n5t6DENJNM_3dnUvhkxegiLLEf-eRzRgTbe4iq-_FbrKUmnVm-oNITPLf9Q1yPefECqNN9HUcYk0ri6Ksen4MO5mu7gy7QO3iuuuxo/s400/PMT-%2526-crystal.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Cap glued to PMT (<i>click to enlarge</i>)</td></tr>
</tbody></table>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><div style="text-align: left;">
The plastic crystal is highly fluorescent and glows beautifully under 365nm UV light.</div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgazeJNyDdbew6BUX0HVkRcNjEliKl4CoGkGSO-Gw0JrxNrfWXQbIB9rHG-Lnc8CJg-W-f71WDl70MYpmKnIGDIhGmCtxik08x5W_LXiwZ2MfcuDjoVu7RlwMQRaRtA6CmJNtSaBuefbns/s1600/UV-light.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="656" data-original-width="834" height="313" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgazeJNyDdbew6BUX0HVkRcNjEliKl4CoGkGSO-Gw0JrxNrfWXQbIB9rHG-Lnc8CJg-W-f71WDl70MYpmKnIGDIhGmCtxik08x5W_LXiwZ2MfcuDjoVu7RlwMQRaRtA6CmJNtSaBuefbns/s400/UV-light.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Crystal fluorescing. In a dark room it's quite bright. (<i>click to enlarge</i>)</td></tr>
</tbody></table>
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgn3snc1yHVRCt0s2AEowRbjrM2wPcn6ZncL3xRrosejVcx08pUXWxWIAEUprUUw1ycOz3LocX5Iy3mwiB7_UTuwH2QskFpzTr2eFEW6hFUV0TZaOn-4BCjDV5ZBPUMmaox3ze9v0wkns4/s1600/PMT-%2526-crystal-2.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1567" data-original-width="989" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgn3snc1yHVRCt0s2AEowRbjrM2wPcn6ZncL3xRrosejVcx08pUXWxWIAEUprUUw1ycOz3LocX5Iy3mwiB7_UTuwH2QskFpzTr2eFEW6hFUV0TZaOn-4BCjDV5ZBPUMmaox3ze9v0wkns4/s400/PMT-%2526-crystal-2.jpg" width="251" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Perfect fit (<i>click to enlarge</i>)</td></tr>
</tbody></table>
I did not bother to polish the crystal. I was too nervous at this point to be able to without mucking things up even more. A voice of experience told me not to sweat it so...<br />
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Next up was attaching the crystal to the PMT. I carried the bag of silicone coupling compound to the workbench, went to get something else, sat down and... the silicone grease was nowhere to be found on my cluttered workbench. AUGHHH!<br />
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Fortunately I had some more in another PMT wiring kit but my nerves were wearing thin. I proceeded with taping the crystal to the PMT and quit for the night. The next day I wrapped the entire assembly with layers of electrical tape and glued the front scrim on.<br />
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I took everything into a windowless bathroom and sealed the door. I powered up the Geiger counter and was highly relieved to hear lots of background counts. The relief was well-earned.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgctW6OxzRZCFiaOqI9Dul8365R8NoS6nSG0-IDKC9IL9XmqOU2pCCVjVGIugIxEm-a4oMhW8y5QQ9rJDfp0KOmhZfFI7a0be_QRc6svnAfAcIBNsYXVT_5WVw-9aTrYA4fV8SMPS2V6uk/s1600/Taped.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1097" data-original-width="1572" height="278" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgctW6OxzRZCFiaOqI9Dul8365R8NoS6nSG0-IDKC9IL9XmqOU2pCCVjVGIugIxEm-a4oMhW8y5QQ9rJDfp0KOmhZfFI7a0be_QRc6svnAfAcIBNsYXVT_5WVw-9aTrYA4fV8SMPS2V6uk/s400/Taped.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Taped and working. (<i>click to enlarge</i>)</td></tr>
</tbody></table>
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It took me a couple of weeks to reach a point where I was ready to finish things up with the very large piece of shrink tubing. My job was a bit sloppy but I was satisfied with the result when I heard background counts again. Mission accomplished.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiywiC2R7rz6LNpjsHws91OH75GfFZ6Llz5gc7lnYWESVEKuGks9sqmKE8wyQJOsICKIJaLEHiW0bJ4tz7en5aCd-X4QMOZ6BrxcEKCf4uc9szrXGP4RZ-CIhL3CgIjdTNxIkW3HSFx1Lg/s1600/Shrunk.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="795" data-original-width="1234" height="257" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiywiC2R7rz6LNpjsHws91OH75GfFZ6Llz5gc7lnYWESVEKuGks9sqmKE8wyQJOsICKIJaLEHiW0bJ4tz7en5aCd-X4QMOZ6BrxcEKCf4uc9szrXGP4RZ-CIhL3CgIjdTNxIkW3HSFx1Lg/s400/Shrunk.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Heat shrink shrunk. (<i>click to enlarge</i>)</td></tr>
</tbody></table>
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By the way, if you happen to see a small plastic bag labelled "Silicone" anywhere please let me know.<br />
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<b><i>A big thanks to Tom Hall for this kit and his support. A very special thanks to K0FF without whose help none of this would have been possible let alone gotten done. Bravo.</i></b><br />
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[<i>postscript</i>]<br />
<br />
I found the missing silicone grease. It was on my workbench all along amidst the bubble lights. Look closely. Very closely.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh26-58PTRYlWCcWGERa6-CuGGQK4AdGE-AODdRAfe0C4C6WhOLJ9lqxu4yl0sWSb82k3lt_ejG8fEoyN6s3k2Ujzgp_qBebP8Cg-uAsLsvW0vKZ39IZ4YBqD9zx7WwhpAqKIPtN_CHnGk/s1600/Silicone-workbench.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1044" data-original-width="1600" height="260" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh26-58PTRYlWCcWGERa6-CuGGQK4AdGE-AODdRAfe0C4C6WhOLJ9lqxu4yl0sWSb82k3lt_ejG8fEoyN6s3k2Ujzgp_qBebP8Cg-uAsLsvW0vKZ39IZ4YBqD9zx7WwhpAqKIPtN_CHnGk/s400/Silicone-workbench.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Closer. Closer... (<i>click to enlarge</i>)</td></tr>
</tbody></table>
Right there the entire time. I told you my eyesight is deteriorating.The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-69450715607963392022016-10-25T15:19:00.000-04:002020-04-10T12:29:06.163-04:00Craig Anderton's Multiple Identity Filter<span style="font-family: inherit;">Craig Anderton's Multiple Identity Filter™ originally appeared in a series of ariticles in <i>Contemporary Keyboard</i> in 1979. It is a CEM3320-based VCF with each of the four stages operating semi-independently. Each stage has...</span><br />
<ul>
<li type="disc"><span style="font-family: inherit;">Three Filter Modes: </span><span style="font-family: inherit;">Lowpass, </span><span style="font-family: inherit;">Highpass, </span><span style="font-family: inherit;">Allpass</span></li>
<li><span style="font-family: inherit;">Two frequency ranges (10:1 ratio)</span></li>
<li><span style="font-family: inherit;">Series/Parallel Switching</span></li>
</ul>
<span style="font-family: inherit;">Add to that voltage-controlled resonance, straight/filtered signal mixer w/phase inverter (for phasing, changing bandpass to notch, etc.) and more. </span><span style="font-family: inherit;">Craig was in top form—this is one tricked-out VCF.</span><br />
<div>
<br /></div>
<span style="font-family: inherit;"></span>
<span style="font-family: inherit;">Here is the article: <a href="http://www.synthdiy.com/files/2002/MIF.pdf">MIF.pdf</a></span><br />
<br />
Here is a mirror on <b><i>Mediafire</i></b> in case the link above doesn't work for you. I've been told that some web browsers (or their extensions) warn that Mediafire is a dangerous site. It's <b><i>not</i></b> but the page does have a lot of extraneous links and other junk that can make it confusing to navigate. To start the actual download of the pdf file click on the big green "DOWNLOAD" button that also has the file size in smaller letters: <a href="http://www.mediafire.com/file/29es58ky30v7467/MIF_%CE%A9.pdf" style="font-family: inherit;">MIF pdf</a><br />
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<span style="font-family: inherit;"><span style="font-size: large;">Update 2017.2.26</span></span><br />
<span style="font-size: xx-small;"><br /></span>
<span style="font-family: inherit;">Note that this design is not optimal. More work has to be done to get the stages to "behave" properly. This has been discussed on the Synth DIY list on multiple occasions. There is a searchable archive here: </span><a href="http://synth-diy.org/pipermail/synth-diy/" style="font-family: inherit;">SDIY Archive</a><br />
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And there's some very good news: a clone of the CEM3320 has been fabbed. It's available <a href="http://ericasynths.lv/en/shop/diy/diy-accessories/voltage-controlled-filter-as3320/">here</a> and the price is very reasonable. The datasheet is <a href="http://www.alfarzpp.lv/eng/sc/AS3320.pdf">here</a>.The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com1tag:blogger.com,1999:blog-1290923408109546049.post-72088602035753561312016-02-24T14:28:00.000-05:002020-04-10T12:41:23.062-04:00The Oscilloscope Artist<b>The Oscilloscope Artist</b> originally appeared in the November, 1975 issue of <i>Popular Electronics</i>. It creates all sorts of fascinating moving geometric patterns on an oscilloscope screen.<br />
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<a data-jsbanchorprepared="IsC6UJw7dm5278L" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEglm7UNvNyz0KlpUfnD8LTddy6S5F4Wi-7KN3EnMcuO8uMvQvzYyWUTq0DVZ1h2DDgIligrZ-2IdD6gYf25Vabjs5vVfMqmcyhd80bJDX6ENtbnVETyYoZQ5exhMhNqZNtGzYUEvPiGDR8/s1600/Example1.JPEG" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEglm7UNvNyz0KlpUfnD8LTddy6S5F4Wi-7KN3EnMcuO8uMvQvzYyWUTq0DVZ1h2DDgIligrZ-2IdD6gYf25Vabjs5vVfMqmcyhd80bJDX6ENtbnVETyYoZQ5exhMhNqZNtGzYUEvPiGDR8/s400/Example1.JPEG" /></a>All you need is a low bandwidth 'scope with horizontal and vertical (XY) inputs.<br />
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<span style="font-size: large;">Updates</span> (2018/02/16):<i> David Dixon spotted a <b>really</b> <b>stupid</b> typo in the original pdf file that was shared below. This has been</i><i> fixed and t</i><i>he latest version is now 1.2.1. All other (unattributed) copies floating around the Internet are of the earlier, incorrect version.</i><br />
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<i>(2020/04/10): A new PC board layout using TL074 quad op-amps is now available as well as etched boards! Message me. </i><br />
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A reconstruction of the complete article is in a <a data-jsbanchorprepared="ipylNGWRBqc9Px4" href="http://www.mediafire.com/file/1vllwt7n532m0l1/Scope%20Artist%201.2.1.pdf"><b>pdf file</b></a>. All of the original parts are still available!<br />
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The original block diagram is a bit confusing so I redrew it. Oscillators A & D create a Lissajous figure baseline from triangle/square waves. Oscillators B & C are multiplied and summed with A & B.<br />
<a data-jsbanchorprepared="3C83bLk0rQz7fvd" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhuwK46w3Pl67zTGv79HeE4fa2NpqfIB0Le8j6DSNKY0Ch15_eB1h03STTVmDoHM9vjpS7tSt9MHsptOBG17i5dVAbXTmLQIGBscO4jvCgrEK17TfLImv76e782d1ZM3QGWQn8GaQAonUg/s1600/Block+diag.jpeg" imageanchor="1"><img border="0" height="197" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhuwK46w3Pl67zTGv79HeE4fa2NpqfIB0Le8j6DSNKY0Ch15_eB1h03STTVmDoHM9vjpS7tSt9MHsptOBG17i5dVAbXTmLQIGBscO4jvCgrEK17TfLImv76e782d1ZM3QGWQn8GaQAonUg/s400/Block+diag.jpeg" width="400" /></a><br />
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<a data-jsbanchorprepared="ubKBZqnsBUbbyVe" href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhqESqDWP4fxKvfHotLOFEGC3ApOsqNubrJ1a_8fmTtSVI5u1UQc_nzWgzEB61xs59w488QrWxoBApp-1kFWyp26F2hwaxZQPErHBu51AfVAiNS9dl2AydUllntiLYAt4rzjVHLJFw6p9g/s1600/Example2.JPEG" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhqESqDWP4fxKvfHotLOFEGC3ApOsqNubrJ1a_8fmTtSVI5u1UQc_nzWgzEB61xs59w488QrWxoBApp-1kFWyp26F2hwaxZQPErHBu51AfVAiNS9dl2AydUllntiLYAt4rzjVHLJFw6p9g/s400/Example2.JPEG" /></a></div>
To make things interesting, C is 90° out of phase between the multipliers. All the oscillators are sync'd to A, which is ~60Hz. All of this produces complex patterns which move and shift.<br />
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I've also used it with a laser projection system with X and Y galvos and it works although the corners aren't too sharp.The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com1tag:blogger.com,1999:blog-1290923408109546049.post-64669365420034302942011-11-04T19:03:00.002-04:002020-04-10T12:43:07.650-04:00Halloween 2011<span style="font-family: inherit; font-size: small;"><span style="font-size: medium;">Update:<i> Photobucket is now useless and clicking on images doesn't enlarge them. I'm working on an alternative.</i></span></span><br />
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<span style="font-family: inherit;"><span style="font-size: large;">Update #2:<i> Photos FIXED.</i></span></span><br />
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Another Halloween come and gone. I'm rather worn out from setting it all up and taking it all back down. Sadly, this was to be the last year we could decorate before the house was sold. Fortunately, 2011 turned out to be the year that I finally managed to completely set up the lights in the yard and I managed to add a few more to the porch.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj7vJx5pnqUpBdK0DGvfgd-ngzDI2mFZIZyEc4X51a9iSnbFDLcBjtQfAehY3lK2PXa53Y_dEVAdHc2eKhGjdb1nuYEqK2oa-m2YIoWVz4Eh1vvPsa1qZ_n6uTgFINCmEUKd81IfdjvgYg/s1600/Front-close.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="422" data-original-width="728" height="231" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj7vJx5pnqUpBdK0DGvfgd-ngzDI2mFZIZyEc4X51a9iSnbFDLcBjtQfAehY3lK2PXa53Y_dEVAdHc2eKhGjdb1nuYEqK2oa-m2YIoWVz4Eh1vvPsa1qZ_n6uTgFINCmEUKd81IfdjvgYg/s400/Front-close.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhLUTTzn1HWnmsKVg0iK8ca5E58dpdN8T50KSHero-nZUPPwW2oJofr0SnOgBgXqZqmMbL1gEmJFYPguvOhecttdb4dRWM3b3phyphenhyphen2ajvBv_ojZT4C605TNey0BAvvmaPc5stCalgmh9mCU/s1600/East-end.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="537" data-original-width="1020" height="210" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhLUTTzn1HWnmsKVg0iK8ca5E58dpdN8T50KSHero-nZUPPwW2oJofr0SnOgBgXqZqmMbL1gEmJFYPguvOhecttdb4dRWM3b3phyphenhyphen2ajvBv_ojZT4C605TNey0BAvvmaPc5stCalgmh9mCU/s400/East-end.jpg" width="400" /></a></td></tr>
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiWGJJ1SpmJxdtZheqoTxohtGKBVw4SnZVzL-GXr-trdWSO4cxK3Lu8MfFD_UYZYks8hESVSb3puUKjzkf-FWVY62cAG63EeyyRxKsdiHAHODa1ETsXK8oMmzOe1gk5Wy1M43Hbi-7xd7Y/s1600/West-end.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="463" data-original-width="891" height="207" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiWGJJ1SpmJxdtZheqoTxohtGKBVw4SnZVzL-GXr-trdWSO4cxK3Lu8MfFD_UYZYks8hESVSb3puUKjzkf-FWVY62cAG63EeyyRxKsdiHAHODa1ETsXK8oMmzOe1gk5Wy1M43Hbi-7xd7Y/s400/West-end.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table>
<br />
And finally here's the BIG picture (it may look small but that's because it's too big to fit):<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg8uR0Neno4NbH9zbk6V-8UcMUNrych4m_QFBlMlWDpHN2g4x2Qa7Q_Phs8Fb3q4IFEk0NkxzJcq7XVX25KDNX4rJ1Anzz5-lwg71BjOrEbt4nF98EaRdJUkRjIMMuBrtRPhsiIYv0nXYE/s1600/Front.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="297" data-original-width="1143" height="103" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg8uR0Neno4NbH9zbk6V-8UcMUNrych4m_QFBlMlWDpHN2g4x2Qa7Q_Phs8Fb3q4IFEk0NkxzJcq7XVX25KDNX4rJ1Anzz5-lwg71BjOrEbt4nF98EaRdJUkRjIMMuBrtRPhsiIYv0nXYE/s400/Front.jpg" width="400" /></a></td></tr>
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Everyone said it looked great.<br />
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There's one bulb blown in the final panorama. Look closely.🔎 Very closely...🔬<br />
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If you find it leave a comment.The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com1tag:blogger.com,1999:blog-1290923408109546049.post-53441461788000112752011-08-21T19:36:00.010-04:002011-09-01T16:56:52.515-04:00Room temperature diamagnetism with pyrolitic graphite<span class="Apple-style-span" style="font-size: large;">Updated</span> 2011.09.01<br />
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I just acquired some <i>pyrolitic graphite</i> and powerful neodymium magnets from <a href="http://unitednuclear.com/index.php?main_page=product_info&cPath=70_71&products_id=527">United Nuclear</a>. Pyrolytic graphite has the highest <a href="http://en.wikipedia.org/wiki/Diamagnetism">diamagnetism</a> of any room temperature material [see correction below]:<br />
<blockquote>
<i>Diamagnetism</i> is the property of an object which causes it to create a <a href="http://en.wikipedia.org/wiki/Magnetic_field">magnetic field</a> in opposition to an externally applied magnetic field, thus causing a repulsive effect. Specifically, an external magnetic field alters the orbital velocity of electrons around their nuclei, thus changing the <a href="http://en.wikipedia.org/wiki/Magnetic_dipole_moment">magnetic dipole moment</a>. According to <a href="http://en.wikipedia.org/wiki/Lenz%27s_law">Lenz's law</a>, these electrons will oppose the magnetic field changes provided by the applied field, preventing them from building up. The result is that lines of <a href="http://en.wikipedia.org/wiki/Magnetic_flux">magnetic flux</a> curve away from the material.</blockquote>
Here are some small pieces of pyrolitic graphite on top of four 0.5" square neodymium magnets:<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiTYKJwcz53RRNLpBEKpvnnwzndWOo_gBIv2Aklx9X7HjQ2XEWtWb9TB-_NLM92iKOUpP11j63y0BEbbWUhal_ihM-nA2nL5ykN7c53m0q5MkY8obgQt5x-RCU6OVX_OfFGLMEceoIdoQI/s1600/Diag-carbon2.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="264" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiTYKJwcz53RRNLpBEKpvnnwzndWOo_gBIv2Aklx9X7HjQ2XEWtWb9TB-_NLM92iKOUpP11j63y0BEbbWUhal_ihM-nA2nL5ykN7c53m0q5MkY8obgQt5x-RCU6OVX_OfFGLMEceoIdoQI/s400/Diag-carbon2.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table>
<div class="separator" style="clear: both; text-align: left;">
This is <i>not</i> magnetic repulsion. If that were the case the pieces of graphite would simply fly off the magnets. The magnetic field is strongest at the edges of the magnets so the largest piece is trapped in the center; it's pushed inward to the point of least magnetism. If perturbed it will snap back to this same point and orientation. The smaller pieces are standing on edge because they are repelling the magnetic field on both sides and can't fall over. If one is pushed over it will immediately snap back into a vertical position.</div>
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In this view you can clearly see the largest piece levitating and the smaller pieces standing on edge. The medium size piece is tilted slightly. This may be because its thickness is slightly uneven, which would make the repulsion slightly stronger on the more massive side. This calls for more experimentation.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEimbOUhjrn3pq85iAEVbPAd4NRjClULQWAAL6mOkKQBYpOAwqjBt5NY-WmsMBPeKmwQgwB78P34xHrqqYDaf9S1TSzn6T5OHOyUWk1qiL3gEjElL2Y_GYRBMiwygldgvgTCYubzFmyzVqo/s1600/Diag-carbon.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="155" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEimbOUhjrn3pq85iAEVbPAd4NRjClULQWAAL6mOkKQBYpOAwqjBt5NY-WmsMBPeKmwQgwB78P34xHrqqYDaf9S1TSzn6T5OHOyUWk1qiL3gEjElL2Y_GYRBMiwygldgvgTCYubzFmyzVqo/s400/Diag-carbon.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table>
Needless to say this behavior is completely unintuitive and surprising. When pushed the pieces react in a totally unexpected way. It's as if they've fallen into a sort of bizarre magnetic well. Here's a video <a href="http://www.youtube.com/watch?v=Ij72BJesb3g">showing this behavior</a> in real time.<br />
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Superconductors have an even more powerful diamagnetic effect but require liquid nitrogen to cool them sufficiently.<br />
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I'll have more on this topic in the future as I've also acquired some bismuth, which has the highest room temperature diamagnetism of any <i>metal</i>.<br />
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<span class="Apple-style-span" style="font-size: large;">Correction</span> (2011.08.31)<br />
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Here's the difference between bismuth and pyrolitic graphite (without the math):<br />
<br />
"The most strongly diamagnetic material is <a href="http://en.wikipedia.org/wiki/Bismuth">bismuth</a>, although <a href="http://en.wikipedia.org/wiki/Pyrolytic_carbon">pyrolytic carbon</a> may have a [lower] susceptibility <i>in one plane</i>."<br />
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<br /></div>
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So there you have it. I played around with some bismuth the other day and it was quite interesting. Stay "tuned"...<br />
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<span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; font-size: medium; line-height: 25px;">✴</span></div>
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The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com1tag:blogger.com,1999:blog-1290923408109546049.post-30589104997239841772011-08-19T19:46:00.002-04:002012-01-04T21:21:15.770-05:00Crookes tube first testMy Crookes tubes showed up today and I had time to get a couple of quick shots of magnetic deflection in action with my invisible magnet:<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh8pXD6klK_b7n6eooNc3j5wBucDK9sA8yLXKz6W8GUWV18gCnQMWZMq3dxO4ActLQrKs9lKrDDN_dusSoJE5NshRiRjIU-YBTt4y5ra1pyd6s6UHTIrpW1KavzX_c2i0EYw4NdVsEZKhU/s1600/Mag-tube-up.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh8pXD6klK_b7n6eooNc3j5wBucDK9sA8yLXKz6W8GUWV18gCnQMWZMq3dxO4ActLQrKs9lKrDDN_dusSoJE5NshRiRjIU-YBTt4y5ra1pyd6s6UHTIrpW1KavzX_c2i0EYw4NdVsEZKhU/s1600/Mag-tube-up.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Up</td></tr>
</tbody></table>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiNVXZJtm8LLd7Kec5kojgME-t6mXNSF8xW_XcnwO_m4kpksL9BoMsU4pACFLeMEOJqqurHCEyS0r1bZe6hA-oSc2RrBmvBIxfuaMF1JVWyKunS1GUZqaIPaPhDX-P9y5A81a8OLl71c6w/s1600/Mag-tube-down.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiNVXZJtm8LLd7Kec5kojgME-t6mXNSF8xW_XcnwO_m4kpksL9BoMsU4pACFLeMEOJqqurHCEyS0r1bZe6hA-oSc2RrBmvBIxfuaMF1JVWyKunS1GUZqaIPaPhDX-P9y5A81a8OLl71c6w/s1600/Mag-tube-down.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Down</td></tr>
</tbody></table>
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<div style="text-align: center;">
<span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; font-size: 14px; line-height: 25px;">✴</span></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-3768609175861232622011-08-18T17:17:00.001-04:002011-08-19T19:51:41.637-04:00Induction coil—another new toyI have a bunch of HV stuff coming in this week, starting off with this induction coil:<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh5P61TYTEAfbxEiNWxDS-1I3tbWh42U_r6adV_ACUzF9XllQjNaUOO4IusgqKBUkt8sqsWawfPhQYwGxPJx1RWJVevVlBkZcOyhdNrGw-elNc1e_i6EqfrbNqPT2Bz_elax2fAfZd38hw/s1600/Induction-coil.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="261" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh5P61TYTEAfbxEiNWxDS-1I3tbWh42U_r6adV_ACUzF9XllQjNaUOO4IusgqKBUkt8sqsWawfPhQYwGxPJx1RWJVevVlBkZcOyhdNrGw-elNc1e_i6EqfrbNqPT2Bz_elax2fAfZd38hw/s400/Induction-coil.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table>I got it from <a href="http://www.sci-supply.com/closeup.asp?cid=204&pid=243&offset=0">Sci-Supply.com</a>. I'm going to be powering Crookes tubes with it so I didn't pay the extra money for something bigger. Once you get over 15-20kV X-rays become a hazard. I have enough problems already. Like the fact that my Crookes tube order is sitting in a facility in Michigan and not moving. So much for Priority Mail.<br />
<br />
<div style="text-align: center;"><span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; font-size: 14px; line-height: 25px;">✴</span></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-68941707385529720802011-08-17T17:03:00.003-04:002011-08-17T17:07:12.472-04:00Ball gap for the Dirod electrostatic generatorI finally have the ball gap to show off. It's not finished—the capacitors (Leyden jars in the old days) are rather crummy and will probably have to be redone but I managed to get some action shots anyway.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi0umT_aovQmSt06UA0p6sPvCWYYjmlLVkGUznCAqlY76xLqqf8HRjHSdLOpvxlvWCV-n7lS75XediL35ztoQGVD204OKC5sfBxnRYLr8UCbxzdAz_EoIez3y4UMvqC4OICumnroBTmPdo/s1600/Ball-gap.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi0umT_aovQmSt06UA0p6sPvCWYYjmlLVkGUznCAqlY76xLqqf8HRjHSdLOpvxlvWCV-n7lS75XediL35ztoQGVD204OKC5sfBxnRYLr8UCbxzdAz_EoIez3y4UMvqC4OICumnroBTmPdo/s1600/Ball-gap.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Snap</td></tr>
</tbody></table><div class="separator" style="clear: both; text-align: center;"></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgGbOo1GPSRbnAEdatDrh-ok_MdmzIDRzCxCX2LdvRzY_J3DyKGAmBTvFo5rggxdNnpCg3UAiNd0Asl71Yf43Z3KEw3EnK_dpJi8SChZtaZ5YlPE_G35vyWbf1cCWBURDuHYoppOCV3FrA/s1600/Ball-gap2.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgGbOo1GPSRbnAEdatDrh-ok_MdmzIDRzCxCX2LdvRzY_J3DyKGAmBTvFo5rggxdNnpCg3UAiNd0Asl71Yf43Z3KEw3EnK_dpJi8SChZtaZ5YlPE_G35vyWbf1cCWBURDuHYoppOCV3FrA/s1600/Ball-gap2.jpg" /></a></td></tr>
</tbody></table><div class="separator" style="clear: both; text-align: left;">Construction is simple, just follow the instructions at the end of the manual. I had to guess at the tubing lengths but this seems about right. The most time-consuming part was cutting the bases off the dummy doorknobs. Sadly, my camera was occupied with time-lapse experiments and I didn't get any pictures of the process. It took a couple of hours, a moto-tool with an emery wheel, face mask and goggles. The trick is to cut the metal in narrow strips, working them down until they're small enough that they can be broken off with pliers. I slowly worked my way around until the knob came loose.</div><div class="separator" style="clear: both; text-align: left;"><br />
</div><div class="separator" style="clear: both; text-align: left;">After grinding down the stumps of metal stick out of the knobs I glued them to pipe caps with metal-filled epoxy. They don't look as snazzy as I'd hoped but they do work.</div><div class="separator" style="clear: both; text-align: left;"><br />
</div><div class="separator" style="clear: both; text-align: left;">With the capacitors I get a very loud snap with a .75" gap. It's the middle of summer right now; next winter will be the real test.</div><div class="separator" style="clear: both; text-align: left;"><br />
</div><div class="separator" style="clear: both; text-align: center;"><span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; line-height: 25px;">✴</span></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com2tag:blogger.com,1999:blog-1290923408109546049.post-40879823268645323772011-08-08T16:28:00.007-04:002022-04-09T17:07:29.929-04:00Laser power testing<span class="Apple-style-span" style="font-size: large;">Prologue</span><br />
<br />
Several months ago I set out to measure the powers of all my lasers. What seemed like a simple process became a protracted hassle. As with my <a href="http://astarcloseup.blogspot.com/2011/04/building-dirod-electrostatic-generator.html">Dirod electrostatic generator</a> I made a number of mistakes. First the DVM module that I had on hand wouldn't work so I had to buy another one. Next I discovered that the power sensor and DVM grounds have to be separate so I had to come up with another power supply for the DVM. Then I discovered that the IR output from the DPSS lasers was so high that I needed a filter in order to measure the visible output alone. Finally, I checked my meter's sensitivity using the supplied test circuit. That last thing didn't get done because I was futzing around with everything else. When I <i>finally</i> got around to it I discovered that I needed to use the power sensor's built-in shunt resistor to get accurate readings.<br />
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At this point I'm visiting this topic for the third time now. The second post was never finished and the first one has been deleted because all the readings I got were completely wrong. Let's start all over from the beginning...<br />
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<span class="Apple-style-span" style="font-size: large;">Test Rig</span><br />
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The first thing I had to do was build a test rig. Here's the cradle before its paint job:<br />
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiKi9t3M0IApM7oXn4q2vaRsIrwjNWziCjIOHJa_whZqFBSTxI00GpzxXJz6sJ9BqFjvWx6naM2Rat5tVlgp4OngFFgj9Kba0Oa5I8AScC8qoXeDoaGWb3jqP-fm6sH4EopfnQ3EeI1MB0/s1600/Green-on-cradel.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiKi9t3M0IApM7oXn4q2vaRsIrwjNWziCjIOHJa_whZqFBSTxI00GpzxXJz6sJ9BqFjvWx6naM2Rat5tVlgp4OngFFgj9Kba0Oa5I8AScC8qoXeDoaGWb3jqP-fm6sH4EopfnQ3EeI1MB0/s1600/Green-on-cradel.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Out the anode</td></tr>
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The next thing I acquired was a 200mW Calibrated Laser Power Meter Sensor from <a href="http://shop.ebay.com/lasersbee/m.html?_nkw=&_armrs=1&_from=&_ipg=&_trksid=p3686">Lasersbee</a>. You simply attach it to a Digital Voltage Meter and the reading in millivolts is the power of the laser. The power sensor is calibrated for 650nm lasers. For other wavelengths a conversion chart is provided. To make things look cool I bought a back-lit DVM module from Jameco. I found that the sensor and the DVM module need to have separate power supplies to work properly together. Right now I'm using batteries. For the sensor I got a lithium 9V from the local Batteries Plus store. It should last forever as far as this project is concerned. The DVM module is running off of AA batteries.</div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgT4ZJwkgJ67UX9yJoi8YM01Vg85wdQEm6BfUcsFIW95VZWXE_sswiES0xSFYZ0_nN1nNfg7-otHviNovrcWGqqlCpWiY3YjJs953yH8GVo8Upe7bT996OWX_te5ny-qSFRTy8vgqFXmLo/s1600/HLPM-II.jpg" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgT4ZJwkgJ67UX9yJoi8YM01Vg85wdQEm6BfUcsFIW95VZWXE_sswiES0xSFYZ0_nN1nNfg7-otHviNovrcWGqqlCpWiY3YjJs953yH8GVo8Upe7bT996OWX_te5ny-qSFRTy8vgqFXmLo/s1600/HLPM-II.jpg" /></a>The sensor itself appears to be some sort of photovoltaic device. It's relatively small so it can be tricky getting the entire beam aimed at it. Unlike gas tube lasers, diode lasers have an output beam that's rectangular rather than circular. The beam has to be collimated to bring it to a point. My 405nm Blu-ray diode laser is so poorly collimated that it isn't possible to get the entire beam on the sensor even with it rotated 45° (making it go corner-to-corner)</div>
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<span class="Apple-style-span" style="font-size: large;">Laser Pointers</span><br />
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Laser pointers are a very popular item these days. They're cheap and the green ones are very bright to the eye. I got mine from <a href="http://www.dealextreme.com/">DealExtreme</a>, one of those "buy direct from China and wait four weeks for it to arrive" places that have sprung up over recent years. Despite the delay everything I've bought from them has been a really good deal. Note that they do offer a lot of junk so <i>caveat emptor</i>. (I don't think I'll be buying any of their condoms.) There are also tons of laser pointers for sale on ebay but it's a crap shoot. Most of the sellers say "5mW" and then lead you to believe it's actually a lot higher. They often take a 5mW and crank the power up. It works—for a while. Take a look at their feedback before you buy. When it comes to diode lasers you typically get what you pay for.<br />
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In some countries you can't import lasers at all so check before ordering. Here in the US you can't import laser pointers >5mW so don't bother ordering anything rated higher. You can, however, buy domestically manufactured "laser parts" of virtually any power. See <a href="http://astarcloseup.blogspot.com/p/mad-science-for-sale.html">Mad Science For Sale</a> for dealers.</div>
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Having said all that, we're about to see that the "≤5mW" rule isn't always followed...<br />
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<span class="Apple-style-span" style="font-size: large;">Power Measurements</span></div>
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I used a fog machine to make the beams visible in the following tests. The density of the fog varies so the brightness of the beam doesn't correspond to the actual power. Also, these are 5 second exposures so the digits on the meter change and blur the readout sometimes.<br />
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First up is the 405nm pointer with a Blu-ray diode. Note that 405nm is near-ultraviolet so you really don't want to be staring into this one. Here's the 405nm in the test cradle:</div>
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj8O3oGAVh7BBff5B2GPD9l_PjKJ0U-aw5X5bLKBAf4w2lgH4PM4G0qU3BNYsus4gGFyr-Kcjpuz2dhstOEHtaY-bCMUH5rDvth5h6ZhbGdWGw5wx-diAFcOjyuVhqHLPrpD_rQIRSxISs/s1600/405nm.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj8O3oGAVh7BBff5B2GPD9l_PjKJ0U-aw5X5bLKBAf4w2lgH4PM4G0qU3BNYsus4gGFyr-Kcjpuz2dhstOEHtaY-bCMUH5rDvth5h6ZhbGdWGw5wx-diAFcOjyuVhqHLPrpD_rQIRSxISs/s1600/405nm.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">405nm ~24mW</td></tr>
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This works out to about 25.5mW give or take the error range. The correction factor for 405nm is so high that the error range is quite large, ± a couple of milliwatts. As it happens, a friend of mine tested this laser with his pro-quality meter (with a pyrometer) and got exactly 24mW so I'd say we're doing pretty well there considering the limited accuracy. And 24mW is a <i>bit</i> higher than 5mW so I definitely need my googles on when working with this one. Shame on Dealextreme for offering 5mW and delivering 24mW.</div>
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<span class="Apple-style-span" style="font-size: large;">DPSS Lasers</span><br />
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Next up are the <a href="http://en.wikipedia.org/wiki/Diode-pumped_solid-state_laser">diode-pumped solid-state</a> or DPSS lasers. They consist of two IR lasers and a frequency-doubling crystal. An 808nm laser pumps a 1064nm laser and its output has its wavelength halved to 532nm. The major hazard of DPSS lasers is that their efficiency is less than 100% so there's plenty of invisible infrared light being emitted. At 5mW or less this is not considered a hazard, but at higher powers it is. Remember, <i>you can't see it so you don't know how bright it is or where it is</i>. Because of this, DPSS lasers over 5mW <i>should</i> have an IR filter on the output. None of these cheap pointers of Asian origin have any discernible IR filtering. See <a href="http://www.youtube.com/watch?v=tSKTPEeYlb8">this video</a> for a demonstration of the problem. Note that you can also find videos that show how to disassemble a pointer and increase the power, burn things, etc. You're on your own with that stuff.<br />
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In order to measure both the visible and IR outputs of my DPSS lasers I had to acquire a good IR filter. In a wild stroke of luck I found a good one on-line for $6. It has some impressive specs:<br />
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<li>Wavelength—Transmission—Color</li>
<li>470.0nm—97.14% (blue)</li>
<li>532.0nm—97.15% (green)</li>
<li>808.0nm—0.09% (IR/near-IR)</li>
<li>1064.0nm—0.53% (IR)</li>
<li>Material: B270</li>
<li>Glass in accordance with MIL-G-174</li>
<li>Surface quality: F/F per MIL-C-48497A</li>
<li>AR coated both sides</li>
<li>Filter Requirements: Angle Of Incidence: 0 +/-5 degrees</li>
<li>In band transmission: >95% @520~ 550 nm</li>
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This filter is perfect. It passes 97% of the green and practically none of the IR. True, I had some trouble finding a way to mount it with the angle of incidence to within ±5°. But I'm going for ballpark measurements here.<br />
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<span class="Apple-style-span" style="font-size: large;">Update:</span><br />
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It finally occurred to me that any assumptions about the absolute power of the IR emissions from these lasers are unfounded. The relative levels of the 808nm and 1064nm lasers are unknown to me. The Laserbee sensor has two different correction factors for the two IR wavelengths—one greater than one, the other less than one. If the ratio of the two were constant then the calculation could be made.<br />
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When I find out more I'll update this article again.<br />
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<span class="Apple-style-span" style="font-size: large;">More Power Measurements</span><br />
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Up first is a pointer of Asian origin that I traded a 405nm for. The picture is a bit dim as I forgot to turn all the lights on at this point and the fog is rather thick:<br />
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgLDgmhkKsbdMbnc4bRgtYd-3JK00JAWwtikIr0ko6khwiizEiMtC2UAzgFMELFD0eac7RqCVMHYSwLz77dwgrKwruE5il3wa3Qp9RiEfeikWIBxnZvA4EpVf71HGJ6KYBiAm4GpYWQw-o/s1600/532-1.1.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgLDgmhkKsbdMbnc4bRgtYd-3JK00JAWwtikIr0ko6khwiizEiMtC2UAzgFMELFD0eac7RqCVMHYSwLz77dwgrKwruE5il3wa3Qp9RiEfeikWIBxnZvA4EpVf71HGJ6KYBiAm4GpYWQw-o/s1600/532-1.1.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">532nm #1</td></tr>
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Unfortunately, I didn't manage to get a decent picture with the IR filter in place but the reading was 1.1mV, which about 1.8mW. With a reading of 4.1mV with all three wavelengths combined, obviously there's a lot of IR emission here and the visible power is well below 5mW.<br />
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Next up is a Dealextreme 532nm. It doesn't look as bright because there's less fog here:<br />
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjt-a0q1zQw2Qa3XmKFnkhKgFZg3ogVNe4z_HdqaA0xZ6Mb9dW1n18rFt7O8DyMWgSqLQgPbeEX0RrF4nh0o0MM5ak8mS9_jK6h1Lu3PozHlbK32am8N_uuZVUUf6483iz-CC8UFNwK8d8/s1600/532-2.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjt-a0q1zQw2Qa3XmKFnkhKgFZg3ogVNe4z_HdqaA0xZ6Mb9dW1n18rFt7O8DyMWgSqLQgPbeEX0RrF4nh0o0MM5ak8mS9_jK6h1Lu3PozHlbK32am8N_uuZVUUf6483iz-CC8UFNwK8d8/s1600/532-2.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">532nm #2</td></tr>
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16.3mV combined.<br />
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1gx-rDMmTD3kuMx8IiKyxRGB7TY7fBda65a1CPw8YAkM2FYUaqQirPumt2HpO6uQXotAPh-A_QC3BTdMT-x9Y2Z1BrPMRi2VJhGmK48DSyNht6lOkcsej3CLA-qqpduKQo8Mi1DwspZQ/s1600/532-2-IR.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi1gx-rDMmTD3kuMx8IiKyxRGB7TY7fBda65a1CPw8YAkM2FYUaqQirPumt2HpO6uQXotAPh-A_QC3BTdMT-x9Y2Z1BrPMRi2VJhGmK48DSyNht6lOkcsej3CLA-qqpduKQo8Mi1DwspZQ/s1600/532-2-IR.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">532nm #2 + IR filter</td></tr>
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About 11.2mV (18.25mW) visible. Lots of IR. Say, wasn't this supposed to be "≤5mW"? Heh.<br />
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Up next is my AixiZ 50mW OEM diode head:<br />
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi2pP-yNY-cwGJBPW_dLYkZ0kc85B_qJG81g8eX0i_-exz20_pI6I3GCZlBCx168eW6t3C01zKrNcAj0WZhkviBxClODUR13yVM10jiqB997-cRv4LVjmLv5uDS7m7cVhlHtJXlBhpHoew/s1600/532-50.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi2pP-yNY-cwGJBPW_dLYkZ0kc85B_qJG81g8eX0i_-exz20_pI6I3GCZlBCx168eW6t3C01zKrNcAj0WZhkviBxClODUR13yVM10jiqB997-cRv4LVjmLv5uDS7m7cVhlHtJXlBhpHoew/s1600/532-50.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">532nm #3</td></tr>
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjGy5Vg7d0diiXZ2bt5xtMXFlnTRtDBlYBG1FLmsTNqlYBNH8mzYKa580RbtSWIHd4YJa6cQeGMedZSqCQN94CecNcj7RsVp-C1umwtGmGVvHY1u0IscTCZJRxNOXP7yY2OKcJ00bo8KPY/s1600/532-50-IR.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjGy5Vg7d0diiXZ2bt5xtMXFlnTRtDBlYBG1FLmsTNqlYBNH8mzYKa580RbtSWIHd4YJa6cQeGMedZSqCQN94CecNcj7RsVp-C1umwtGmGVvHY1u0IscTCZJRxNOXP7yY2OKcJ00bo8KPY/s1600/532-50-IR.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">532nm #3 with IR filter</td></tr>
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About 60.6mW visible. Clearly this laser has some IR filtering but I can't tell how much. 50mW is <i>very</i> bright. I had to wear safety goggles to align the beam.<br />
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Fortunately, unlike the visible beam, the IR isn't well collimated because of the large difference in wavelength. It's spread out over a larger area which reduces the danger slightly. In this picture, I have the 50mW head shining through my googles, which have an O.D. of 7+ at 532nm and pass nothing but a faint, tiny yellow dot of light. They attenuate the IR as well by at least 40% but a lot still makes it through. Beyond the goggle lens is an IR detector. As you can see, the dot is quite large:</div>
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjkzKL2tHWeReoRSsQSWKDTMPZTjmCPF-kXhvZcdtnxzLPPL6zhgfv-Inl8sGIrxM_MoHBCpCbnOgt6WroVk-VVqJ1WembCYXQlTu8lTITOIc8ALN6eOBTxZcqCp70c786WUkCu7M80W3U/s1600/50mW-thru-goggles-33%2525.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjkzKL2tHWeReoRSsQSWKDTMPZTjmCPF-kXhvZcdtnxzLPPL6zhgfv-Inl8sGIrxM_MoHBCpCbnOgt6WroVk-VVqJ1WembCYXQlTu8lTITOIc8ALN6eOBTxZcqCp70c786WUkCu7M80W3U/s1600/50mW-thru-goggles-33%2525.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Detecting IR</td></tr>
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<span class="Apple-style-span" style="font-size: large;">Green gas tube laser</span><br />
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While I'm working with green lasers, here's a 543.5nm helium-neon gas tube laser:<br />
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjh0PeosDvc35xmeu3DVyplIteSZwXi1TUMTCxgs7yrmTOJeN0zfr8VmXNY0lYJz_aO21CB61J7tuzJGfg1lyOhZEv_ohyQHlpSG3RAlZS7fO-v3og4t40crfZhZpgPOdQqbv5cLd-lTcc/s1600/HeNe-2mW.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjh0PeosDvc35xmeu3DVyplIteSZwXi1TUMTCxgs7yrmTOJeN0zfr8VmXNY0lYJz_aO21CB61J7tuzJGfg1lyOhZEv_ohyQHlpSG3RAlZS7fO-v3og4t40crfZhZpgPOdQqbv5cLd-lTcc/s1600/HeNe-2mW.jpg" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">543.5nm HeNe</td></tr>
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That's about 1.8mW, which is nominal for this tube. Tubes use high voltages and glow like a neon sign screaming "Mad Scientist," which is their whole appeal. The power supply for this one is 2600V at 6.5mA. I know I'll never see another large green tube again (actually, a used head went really cheap on ebay the other day but anyway...). I'm still looking for orange and yellow...<br />
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Laser tubes have a very small, round (Gaussian curve) bean with a <i>very</i> low divergence. Here's the entire tube in all its glory:<br />
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<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgubso5h6Xf9MLLnphdeDxsQqkRxfHr_Nm3fAmg4ph93fmov7NxTi0fygcO32BGDXX9N5KnLmdCXiuJREMfUEEoUxLcACEagiyotPdXdBIGxJ8fW931TZaIV6euhVgPgyLJQU2Vdd4Pu2Q/s1600/HeNe-2mW-entire.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="260" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgubso5h6Xf9MLLnphdeDxsQqkRxfHr_Nm3fAmg4ph93fmov7NxTi0fygcO32BGDXX9N5KnLmdCXiuJREMfUEEoUxLcACEagiyotPdXdBIGxJ8fW931TZaIV6euhVgPgyLJQU2Vdd4Pu2Q/s400/HeNe-2mW-entire.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Out the cathode—Click to enlarge</td></tr>
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Now you can see what the rest of the test cradle is for. At 19" it's the longest tube in my collection. A red laser tube this size would probably be 20mW. Green is not very efficient. Note that this tube is emitting from the cathode. I have another green tube in my collection that emits from the anode (it's in the first picture at the beginning of this post). It's 0.1~0.2mW. That's <i>tenths</i> of a milliwatt. The beam is so dim you can stare straight into it—not that I'm recommending that...<br />
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Next time around—lasers of the visible red kind.<br />
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The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com1tag:blogger.com,1999:blog-1290923408109546049.post-75432839586990250752011-08-03T15:15:00.017-04:002022-04-09T17:08:11.019-04:00Calculator HeavenIn this age of instant karma and overnight obsolescence it may seem surprising that decent calculators are still being manufactured. Fortunately, that's <i>one</i> thing about HP that hasn't changed in recent years.<br />
<br />
Several years ago my beloved <a href="http://www.amazon.com/HP-HP20S-Scientific-Calculator/dp/B00000JBLP/ref=sr_1_6?s=electronics&ie=UTF8&qid=1312496273&sr=1-6">HP 20s</a> suddenly died. I turned it off, then back on—nothing happened. Dead. I bought a new calculator at Walmart. It was only $12 for a TI with all the same features but it was the flimsiest piece of crap I've ever attempted to use. The buttons have no tactile feedback and don't even make contact about 10% of the time. I can do the same operation three times and get three different results. I've been feeling calculator buttons in stores looking for something like the good old days but everything feels like mush. At least I haven't been accosted by store security yet for feeling up their merchandise.<br />
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</div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhca5cRRPLOHs1gD1OknR6S37qvp75oDFoV_KOW94skgEUqNirw4gfYhTccPjrg-bDBUW_SYz1SGkAByOYjkEUX0LpGqtGYelX0jY3CjvJc_Yuc2hVjV7BEVl-HiC25Le3pxgcTnhECUww/s1600/Calc3.png" style="margin-left: 1em; margin-right: 1em;"><img border="0" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhca5cRRPLOHs1gD1OknR6S37qvp75oDFoV_KOW94skgEUqNirw4gfYhTccPjrg-bDBUW_SYz1SGkAByOYjkEUX0LpGqtGYelX0jY3CjvJc_Yuc2hVjV7BEVl-HiC25Le3pxgcTnhECUww/s1600/Calc3.png" /></a></div><div class="separator" style="clear: both; text-align: center;"><br />
</div>After seeing used used calculators going for ridiculous price to HP addicts and collectors I finally broke down and bought the newer <a href="http://www.amazon.com/HP-F2215AA-ABA-Scientific-Calculator/dp/B000TDRHG8/ref=sr_1_3?ie=UTF8&qid=1312397714&sr=8-3">HP 35s</a>. The keys aren't quite as stiff as before but they still have that solid feel I've been missing. As a bonus I've completely given up algebraic entry for <a href="http://en.wikipedia.org/wiki/Reverse_Polish_Notation">RPN</a>. I put it off for decades but not any longer. Fortunately I have experience using a stack-oriented programing language (FORTH) so RPN is a snap for me.<br />
<br />
It's so nice to know that it got entered right the first time every time.<br />
<br />
<div style="text-align: center;"><span class="Apple-style-span" face="Arial, Tahoma, Helvetica, FreeSans, sans-serif" style="color: yellow; font-size: 14px; line-height: 25px;">✴</span></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-14084112867930713342011-08-01T19:24:00.000-04:002011-08-01T19:24:56.152-04:00Lots of detail todayTook one look in the eyepiece today and knew I'd hit the jackpot. Sunspots so big I could use them to focus in live view:<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjpyZ736q5JwfEsizK25MlHmGm4O4zgbujjVhajb3fcthsox5Es0orwcei5p0eowIYJcGCK9QCghy0j1g4KSKUJVU8d0VJyjbKE1HggFwhkb15Zf7XLXwb8kyF2JToqy5VHd_kj39flrBU/s1600/1579-tuned-color.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="319" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjpyZ736q5JwfEsizK25MlHmGm4O4zgbujjVhajb3fcthsox5Es0orwcei5p0eowIYJcGCK9QCghy0j1g4KSKUJVU8d0VJyjbKE1HggFwhkb15Zf7XLXwb8kyF2JToqy5VHd_kj39flrBU/s320/1579-tuned-color.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table>Unfortunately I've still got uneven illumination and it appears that the 2X Barlow has introduced <a href="http://en.wikipedia.org/wiki/Newton%27s_rings">Newton's rings</a> into part of the image (move back a bit and look at the upper left quadrant).<div><br />
</div><div>Fortunately, the spots came out extremely well:<br />
<div><br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjHQ2E_xj0UxRL9CU8m2Tc6hvh4FzHV2VqwPaaDJ6nDq4WVfNGygSHdzgBb-VzOC0qgdoUBlGxh1aZJJTvjH0EAb_viDrXopCNQvavroeU5KBm5WzNjCNymlQpqrqcm-oxODHGfgkOyL7w/s1600/1609-spots.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="115" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjHQ2E_xj0UxRL9CU8m2Tc6hvh4FzHV2VqwPaaDJ6nDq4WVfNGygSHdzgBb-VzOC0qgdoUBlGxh1aZJJTvjH0EAb_viDrXopCNQvavroeU5KBm5WzNjCNymlQpqrqcm-oxODHGfgkOyL7w/s400/1609-spots.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table>Two steps forward, one step back. Another day with sweat in my eyes.<br />
<br />
<div style="text-align: center;"><span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; font-size: 14px; line-height: 25px;">✴</span></div></div></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-17277523693990574642011-08-01T17:02:00.000-04:002011-08-01T17:02:59.083-04:00Yet another dangerJust as I was finishing up a successful round of imaging, <i>this</i> showed up:<br />
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<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjpfIJnAcWtosZ1-M-nNVZEjeWUDydcCoTk50rwqsDxetSTKvyeesrrue3R0ElU3I_-e6ZPWv8EskcF_JbHc2CzVCZYvBRJY56SpBUSWRYzBl-hCAaKVarvwaSTSA1Dp0TxTb9xjVSDLq4/s1600/Insect.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjpfIJnAcWtosZ1-M-nNVZEjeWUDydcCoTk50rwqsDxetSTKvyeesrrue3R0ElU3I_-e6ZPWv8EskcF_JbHc2CzVCZYvBRJY56SpBUSWRYzBl-hCAaKVarvwaSTSA1Dp0TxTb9xjVSDLq4/s320/Insect.jpg" width="297" /></a></div><br />
Good thing I'm not allergic.<br />
<br />
<div style="text-align: center;"><span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; font-size: 14px; line-height: 25px;">✴</span></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-19421998153292099462011-07-17T11:56:00.001-04:002011-07-28T15:10:32.392-04:00The dangers of diurnal astronomy#1—sunburn<br />
#2—sweat in your eyes<br />
#3—overheating laptop computer<br />
#4—see below<br />
<br />
<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgCqwcfWjMkICTlkpOfQbaYYb-pyNQziHdAqEtcaBm8hIF_kJFF8rOySuT-bW7DxA11aeD_AXUGRaDsYcIUKZysmhiXoSyufXuSAe96wCZDCnQvWujQ-li-8qZOTENyjPl1cH_rn-7OoCU/s1600/HDR-bird-crap.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="368" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgCqwcfWjMkICTlkpOfQbaYYb-pyNQziHdAqEtcaBm8hIF_kJFF8rOySuT-bW7DxA11aeD_AXUGRaDsYcIUKZysmhiXoSyufXuSAe96wCZDCnQvWujQ-li-8qZOTENyjPl1cH_rn-7OoCU/s400/HDR-bird-crap.jpg" width="400" /></a></div><br />
<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgy0YEBBNZ_wytPqUi9NtdMJavtlKHR_K0BW-c_edQd8pkvG4-Kqswa57-2vzWmgrqniymLgka8NK5e9oUpjaOHTnMgjjfdQb7JVoWgJtCeK3Dn6yGtTIV54WndnL-RiK_LB8k_uPGAlp8/s1600/Bird-crap-close-20%2525.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgy0YEBBNZ_wytPqUi9NtdMJavtlKHR_K0BW-c_edQd8pkvG4-Kqswa57-2vzWmgrqniymLgka8NK5e9oUpjaOHTnMgjjfdQb7JVoWgJtCeK3Dn6yGtTIV54WndnL-RiK_LB8k_uPGAlp8/s400/Bird-crap-close-20%2525.jpg" width="266" /></a></div><br />
I should add that the cap was off at that moment.<br />
<br />
<div style="text-align: center;"><span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; font-size: 14px; line-height: 25px;">✴</span></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-83013977092884674192011-07-11T12:37:00.000-04:002011-07-11T12:37:34.768-04:00Doing it over againToday I reprocessed an image from the earlier post <a href="http://astarcloseup.blogspot.com/2011/06/best-solar-image-yet.html">Best solar image yet</a> and now it's even better. This image is the closest I've ever come to finding the "sweet spot" and I'll trying imaging from that area again.<br />
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<div class="separator" style="clear: both; text-align: center;"></div><div class="separator" style="clear: both; text-align: center;"></div><div class="separator" style="clear: both; text-align: center;"></div><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhgexVZutEhQdjsX3utOMPSjoREnUVMNsfj3oS3K3bjg-77cXw6g2qhJtVjm2-yodCCKh6T2oQ8N344cF_SJYp7RFzWKg8lyp_8kjl4LJPnvvix-ZzyPfqZsFMVDvyoTvR7l-UbT8K-sPs/s1600/9896-final.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhgexVZutEhQdjsX3utOMPSjoREnUVMNsfj3oS3K3bjg-77cXw6g2qhJtVjm2-yodCCKh6T2oQ8N344cF_SJYp7RFzWKg8lyp_8kjl4LJPnvvix-ZzyPfqZsFMVDvyoTvR7l-UbT8K-sPs/s400/9896-final.jpg" width="391" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table><div class="separator" style="clear: both; text-align: center;"><br />
</div>The ring around the limb is much dimmer and the huge prom at the top is now very clear.<br />
<br />
<div style="text-align: center;"><span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; font-size: 14px; line-height: 25px;">✴</span></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-77468297288609466302011-07-10T14:10:00.001-04:002011-07-11T12:37:52.921-04:00Full disk from yesterdayUneven illumination remains the main problem:<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhCQSA4NFH4bNuKW3UJ0vkTJPEg4C0UMkU8v47YOJ-7J6FVL7kpv7Kg-SkOwVpxwfs_iJxBQo66871imjnyg4-yqFT-0QUAHRXILneuDH8fXayke95FptKbLCG53_FbNKG4zE59tPNKegM/s1600/0023-disk.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="393" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhCQSA4NFH4bNuKW3UJ0vkTJPEg4C0UMkU8v47YOJ-7J6FVL7kpv7Kg-SkOwVpxwfs_iJxBQo66871imjnyg4-yqFT-0QUAHRXILneuDH8fXayke95FptKbLCG53_FbNKG4zE59tPNKegM/s400/0023-disk.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table><div style="text-align: center;"><span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; font-size: 14px; line-height: 25px;">✴</span></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-37278063171934565422011-07-09T16:46:00.002-04:002011-07-11T12:38:22.368-04:00Ring of fireGot some nice proms today:<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9qNUKGbQ0aJe9_UM5aZlBCmMNVwRt5SnDu8SYxzKvlvzlLwQQbQ0xroDdTpSEdktJlU14zLsLrLYwtcLUafx8P9Bzr31DdDKFlhrpsWrid1nMAAgPaQsLkoxhMV7hYAMVGpf7TI8r-hk/s1600/0050-proms.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="390" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9qNUKGbQ0aJe9_UM5aZlBCmMNVwRt5SnDu8SYxzKvlvzlLwQQbQ0xroDdTpSEdktJlU14zLsLrLYwtcLUafx8P9Bzr31DdDKFlhrpsWrid1nMAAgPaQsLkoxhMV7hYAMVGpf7TI8r-hk/s400/0050-proms.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table><br />
<div style="text-align: center;"><span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; line-height: 25px;">✴</span></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-50881631248513229002011-06-30T20:13:00.003-04:002011-07-11T12:38:46.501-04:00Almost in focusToday I used the laptop to focus and then switched to live view for the exposures so I could use the camera's superior histogram:<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhmODJeQFZvQzQlzP0-pXB7kN7e4GNpzU66QPrErstCTo8sbdaHfXzRkKL8xfbwp9hKWcouwILN90uA6trI1d-_DUbQ77ksxUxQRGjpUclBrSo5eREm38EOm0jdrXl07WNxYKEvzj6P8yI/s1600/0006-proms.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhmODJeQFZvQzQlzP0-pXB7kN7e4GNpzU66QPrErstCTo8sbdaHfXzRkKL8xfbwp9hKWcouwILN90uA6trI1d-_DUbQ77ksxUxQRGjpUclBrSo5eREm38EOm0jdrXl07WNxYKEvzj6P8yI/s400/0006-proms.jpg" width="248" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table><br />
<div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgfX59i8Ou6P9o4DxhBadTlKNntcVzltV2qTuIx1EuFHP-RgMwD5hELSMmZO2X-V07M-4l4Wf9jQpqRnkFGrWuD5c9xrBaZi2Dl5MC22ess9nCjQJ1mTm0gjJOBVffeiKf0VGv1EEnSS5A/s1600/Spots.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgfX59i8Ou6P9o4DxhBadTlKNntcVzltV2qTuIx1EuFHP-RgMwD5hELSMmZO2X-V07M-4l4Wf9jQpqRnkFGrWuD5c9xrBaZi2Dl5MC22ess9nCjQJ1mTm0gjJOBVffeiKf0VGv1EEnSS5A/s400/Spots.jpg" width="295" /></a></div><div class="separator" style="clear: both; text-align: center;"><br />
</div><div class="separator" style="clear: both; text-align: center;"><span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; line-height: 25px;">✴</span></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com0tag:blogger.com,1999:blog-1290923408109546049.post-91599824878629622862011-06-29T19:53:00.004-04:002011-07-11T12:39:06.959-04:00Got half of itI guess the "bottom" half is better than nothing:<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjNE_pYLbnH_ytuBvSZRXX2qgNKP8EZ7Kce9x7efJQf-Av9fmYBR2K1lJNqIzkLJ8-JV5W3IEZqGCIaqkXwZJUIqBjjN8LoYBbGPEXU5nCn9ymw70IXcMRAlTcyJuGiQ9_0YHWLEr8B0hw/s1600/0020-cropped-finish.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="221" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjNE_pYLbnH_ytuBvSZRXX2qgNKP8EZ7Kce9x7efJQf-Av9fmYBR2K1lJNqIzkLJ8-JV5W3IEZqGCIaqkXwZJUIqBjjN8LoYBbGPEXU5nCn9ymw70IXcMRAlTcyJuGiQ9_0YHWLEr8B0hw/s400/0020-cropped-finish.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Click to enlarge</td></tr>
</tbody></table>I'm still wrestling with this camera. I managed to get it focussed this time with the use of a laptop but there was no usable data in the red channel of any of my exposures. This image is from the <i>green</i> channel!<br />
<br />
Crystal clear the next two days. Stay "tuned"...<br />
<br />
<div style="text-align: center;"><span class="Apple-style-span" style="color: yellow; font-family: Arial, Tahoma, Helvetica, FreeSans, sans-serif; font-size: medium; line-height: 25px;">✴</span></div>The Mac Doktorhttp://www.blogger.com/profile/08235572436888747948noreply@blogger.com2