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#46
04-30-2014, 08:10 PM
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Tapped into V104 video and V117 (6AT6) 1st Audio.
Got a fair raster, with horizontal tic lines. Picture detail and depth is not good. Barely any audio. Sounds like just the preamp is audible. 
Last edited by M3-SRT8; 05-01-2014 at 09:49 AM. 
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#48
05-01-2014, 10:05 PM
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Tapped into the wrong audio junction point. Tapped into the correct point and was rewarded with audio. Good gain, but I have a buzzy, distorted 4 x 6 cone.
After prodding the voice coil by pushing on the center cap, I believe the coil is not blown or rubbing in the gap. Found that part of the cone is detached from the center cap. After masking off the spider with a trimmed piece of paper (see photo) I applied glue (Titebond) to the torn area and applied light pressure to the speaker cap with a rolled up ball of paper towel and a piece of masking tape. I'll let it dry in place overnight. Fingers crossed.
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#49
05-02-2014, 02:04 AM
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Great sets! I have a very clean 621TS with all original tubes, and only one changed part ever (a power resistor) and it still plays very well. That said, I'd like to see your technique for restuffing the caps and getting the tubulars to look original with the colored wax and hot glue.
Last edited by GKinTN; 05-02-2014 at 02:08 AM.
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#50
05-02-2014, 06:38 AM
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Quote:
Alas, I tried the speaker this morning and it is indeed blown. Bah!
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#51
05-02-2014, 09:09 AM
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I hope that I am not distracting this thread but have a question about the color of the bees wax that you guys are using. I found the stuff at Hobby Lobby and it is great for dipping the capacitors. But it is rather light in color. Did you by chance put some darker coloring in the wax? Possibly using a crayon?
"Just askining..." Thanks for the sidebar...
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#54
05-02-2014, 10:02 AM
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Quote:
Last edited by M3-SRT8; 05-03-2014 at 08:32 AM.
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#55
05-03-2014, 08:35 PM
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I've been running the 621 a few hours each nite on a test pattern, and I've noticed the resolution has pickup up nicely. Looks to be climbing past 3.75 mhz, and the horizontal tics are gone.
I measured the 2nd anode, and the voltage is 9kv. Is that too high for the crt? I'm guessing the CRT and the flyback are burning in. Any guesses out there as to why the picture quality is improving?
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#56
05-03-2014, 09:25 PM
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Could be tubes waking up after being dormant for 50 years, resistors drying out and so forth.
I pulled my set out a few weeks ago and ran it and it looked better than it did a couple years ago when I last fired it up. My CRT is a little slow but it came right up this time and was razor sharp. I made a short video of it: http://youtu.be/DkBcYmZVUkk These sets have a much better picture than any of the 7JP4 based sets I've seen.
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#57
05-03-2014, 10:26 PM
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Yeah. That's what I figure. Shaking out the cobwebs.
Since most of the tubes are original, and haven't been lit up in over 50 years, I guess they're entitled to stretch out a little. I'm going to keep running it, a little longer each day, and see if the picture quality continues to improve.
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#58
05-04-2014, 07:33 AM
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This is wierd. I just fired up the 621 and the picture just compressed horizontally with a audible little "ffft" sound.
I wonder what let loose?
Last edited by M3-SRT8; 05-04-2014 at 07:54 AM.
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