#46
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More pictures:
The high-voltage cage. The empty tube socket in the left-center is for the 1X2B focus rectifier; there may be a solid-state diode underneath and not visible. I plan to restore this whole area back to the original circuitry to the extent I can. The replacement volume/power knob. It looks pretty close to the originals I have seen. The control box and knobs. The knobs are not the originals, but I may have correct ones in a box of knobs I bought years ago. (I know I have at least two, because I just saw them on a wood-cabinet 10" GE that I got without knobs and used ones from the box).
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Chris Quote from another forum: "(Antique TV collecting) always seemed to me to be a fringe hobby that only weirdos did." Last edited by ChrisW6ATV; 01-15-2017 at 09:55 AM. Reason: Updated picture location |
#47
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Wow, the HV might arc a little less if you just cleaned off all that soot!
Getting that Silicone off everything might be a challenge. The Fly's on these don't put out all that much do they, most of it comes from a Tripler circuit doesn't it? |
#48
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nice pics, interesting, had a early projector that had a HV tripler circuit. IS THIS the first commercially used trpler for a TV??
There's a patent link some guys invented in around late 60s for HV tripler ss box? IF let us know of HV setup. this is the case, I'm surprised tripler design wasn't used more-- given all the flyback meltdown issues.
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1977 Zenith Chromacolor II A Very Modern Zenith |
#49
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Philco 48-2500 projection set has a tripler, and I think a number of other early B&W sets do.
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#50
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Quote:
jr |
Audiokarma |
#51
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My mistake, I thought they used that setup.
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#52
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21-CT-55 has a doubler, I think. A single 3A2 for focus, and another 2 for anode supply.
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Evolution... |
#53
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I built a universal adapter for my B&K 467 CRT tester and hooked it up tonight. I have heater-to-red-cathode leakage, so I need to isolate the heater connections. All three heaters light up, and the blue, at least, does show some emission. I did not want to turn the heater voltage up to 6.3v until I get an isolation transformer on there, though.
Do any of you know if I could use an isolation-only booster for a B&W CRT for a test? I do have a couple of them here.
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Chris Quote from another forum: "(Antique TV collecting) always seemed to me to be a fringe hobby that only weirdos did." |
#54
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I tried connecting a B&W brightener in "parallel-isolation" mode after verifying its output voltage seemed OK (connecting the brightener between the tester's heater pins and the CRT), but had no success. I will get a true source of isolated 6.3v for further tests.
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Chris Quote from another forum: "(Antique TV collecting) always seemed to me to be a fringe hobby that only weirdos did." |
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With a 6V, 2A power supply hooked up, the filaments lit up OK. The B&K showed low emission (but not zero) on red and green, and blue was in the low end of the Good scale. I tried the power supply on 7.5V (its next step) for a few seconds, and all three guns read higher (as you would expect), then back down to 6V. Now the blue gun is reading solidly in the Good range, almost half-scale, and staying there. I think it may be time to order some Vacseal!
Also on my list is to see if I could use my Sylvania CK3000 test jig with the CTC-2 chassis. I have already made the adapter for the CTC-4 and CTC-5, but this one is certainly different, with its electrostatic convergence at least.
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Chris Quote from another forum: "(Antique TV collecting) always seemed to me to be a fringe hobby that only weirdos did." |
Audiokarma |
#56
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Chris,
Sounds like your crt is asleep. IF it was my set, I would get the chassis up and running so I could power it under real world conditions, to see if the crt is any good. If it turns out that the tube is under vacuum and you do NOT have the dreaded purple glow, then I would use the Beltron to wake up and CLEAN the dirty cathodes to bring back the emission. Or... if you have a hand held tesla coil, you could also see if the tube is gassy by applying the coil to the neck of the tube. No purple would indicate a tube under solid vacuum, and then I would proceed to the Beltron cleaning to wake it up.
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Vacuum tubes are used in Wisconsin to help heat your house. New Web Site under developement ME http://AntiqueTvGuy.com |
#57
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Bob-
Thank you for the notes. I do not have a Tesla coil, but I will proceed with the chassis restoration. (The set was apparently restored and working about 20 years ago, but I have not yet pulled it out to see the extent and type of work that was done, other than the HV picture above.) My CRT tester is a B&K 467, and it does have a clean/balance function as well as full-on rejuvenate (which would be a last resort, I am sure). I used the same model of tester many times in my work at airports to get good life out of tired tubes, but they were black-and-white CRTs. I will post further as I make more progress.
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Chris Quote from another forum: "(Antique TV collecting) always seemed to me to be a fringe hobby that only weirdos did." |
#58
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If you didn't see a purple glow during the emissions test, then it's probably not gassy. If there was no emission then it could be gassy and not glow, but since you got good emission on the blue gun without it glowing then I think you're o.k.
John |
#59
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before rejuving or cleaning with beltron or any other machine i would run it , after running for a while they may all come up and then there will be no need to rejuve or clean or whatever
mike |
#60
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Like Bob says, won't get true test of (purple) gas indication until all voltages present or a tesla coil is employed.
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Audiokarma |
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