Quote:
Originally Posted by Arcanine
The 6JE6/6LQ6 that's installed in the CTC16 now (Or rather when I delivered it to you) is actually from the CTC20 originally (It's hat looks more like that of a HV Rectifier). I swapped them around. Go ahead and take it out and keep it, and pop my spare RCA back in. That gives you an HO tube for the CTC20 then.
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Last night I tested all lytics in the CTC-16 for capacitance and leakage up to rated voltage with my Heathkit C3. I completely recapped the C2 and C3 (sam's cap number) cans. Can C2 had 2 leaky and one high ESR section out of 4. C3 had one high ESR section out of 2 sections so I decided to replace the whole thing for good measure. C1 tested perfect, no leakage low esr, so it was left alone.
I powered it up with your above suggested H out tube swap and the set came on and ran with H centering jitter for 3-10 min before the width shrank greatly which prompted immediate power down. The new ho tube was drawing more than 5ma more cathode current so swapped back to tube that came in the set when I got it....Cathode current is lower and jitter is not present.
I ran it for 1 hour with h out cathode current metered the whole time (it stayed just below 200mA the whole time) and started to hear HV like sizzling and noticed screen noise/h line jitter (multiple clusters of roughly 1-3 h lines would be off center from the rest). I turned it off and the sizzling stopped with power off, opening the cage revealed very mild wax melt (compared to last time), HV winding rubber tire formed warts between HV rect cap cup and the center. It was hottest beneath wart area. The HV rect tube is a RCA 3A3C the chart calls for a 3A3A....I seem to recall once reading that some variants of that tube caused arcing in the CTC-16, but I can't recall it exactly or find it....Could that be the cause?
The tire was VERY soft and pliable in the wart area. I'm really worried that the flyback might not have long for this world.
Quote:
Originally Posted by Arcanine
And do not buy what the tester says. Jim will chime in and agree, HV Rectifiers never test correctly. They almost always test as bad. Same thing for the Focus 1V2 tube, they test almost bad. You have to remember, the tube usually has 25kW pumping though it, so the tester can't even scratch the surface. Jim and I tested almost 10 of those tubes and they all tested pretty much the same. "Bad"
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I don't put much stock in testers results of sweep tubes, but my tester has notes with the settings HV rects...In the case of the 3A3 it says tube good if reads 40 (in the bad scale range) or more. It read 20, and it's replacement read 90 so that is what went in.
I got the CTC-20 together and was able to get a monochrome picture and sound from it.
I'll post some info/opinions in your CTC-16 fly cooling thread latter I have a certain woman SCREAMING at me to do some remodeling work on the house right now.