Quote:
Originally Posted by walterbeers
I used to change a lot of those color output transistors in Zenith hybrids years ago. Also resoldered a lot of the grounds at the ends of the connection strips. I beleive the transistors replace with an ECG 154 / NTE154, has a round case with a heat sink pushed on the transistors. I would always put a little heat sink compound on it to make sure it made good thermal contact with the push on heat sink.
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Good memory. I don't know about the NTE part number, but the ECG and the rest is spot on. I almost went and put some heat sink compound on, but they did not do that at the factory, and I figured it would be a mess.
The intermittent was really weird as it would respond to both electrical and mechanical stimulus. Sometimes it would respond to a good slug on the cabinet other times not, and if I changed channels(off channel and back) on the turret tuner it would often clear up. Moving the cabinet could affect it, and sometimes checking voltages could get it to behave it's self...Much to my annoyance because usually I would wait for it to act up for a while, and as soon as I would probe for the cause of the symptom the symptom would clear up(thus thwarting all attempts to localize it).
Technicolor: If it helps you get your set working then you win it's contribution to that effort, and the satisfaction of having accomplished that....Ooh! And a banana...
Upon diagnosing and repairing the issue in my set all I got was a better working set, and the immense satisfaction of FINALLY overcoming an issue that was driving me nuts for YEARS.
It was so annoying that if the cabinet was not as sturdy as it is(not a scratch from hand injuring punches) I would have destroyed it already trying to fix the issue percussively. It would do it between once an hour and every three seconds. You have no clue how annoying it is to get up to clear the intermittent go back and the INSTANT you sit down have it go back to a lousy picture...Utterly maddening(and it had a habit of this)!
But I've put many more hours on the clock and she has not lost blue for an instant. It is getting to the point that if the trouble comes back I'd be VERY surprised.
I have over 150$ in this set as I got in an ebay bidding war. This was my first tube color TV. It worked great in the beginning as it was one of Doug's (aka DRH4683) restorations(he even has stuff on You Tube from when he worked on it), but with all the hours I've put on it, so much work has went in to keeping it going that it is probably more my repair work in there than his now. I've probably put more hours on her than the smaller screen living room BPC CRT set has gotten from the whole family over the 5 years I've owned her.