Re: My first foray into Old model TV repairs.
Hello Oliver;
The buck converter was a simple 40 Watt 12 Volt to HT unit I put across the rectified HT points whilst there was the odd missing valve, there fore no heaters. The idea was to ensure the two main smoothing caps did not go bang on mains power, so I started at 50 Volts and went up in 50 Volt stages to 250 Volts with about a day at each level. This was simply because sometime when testing old caps I had some just go short on application of HT.
Now the TV is powered by the mains, new PL81 and PY801 fitted 3 amp fuse in the plug and the 1 amp slow blow fuse on the chassis.
If I get the set going it will have caps replaced, but the initial idea is to try and get some HT running to ensure the LOPT is not duff or I have a bad CRT. The HT is low, but do not know why as yet, I guess I should test the two PY82's for the HT rectifiers and a few valves in the process.
The only other time I have worked on TV's would be some 40 plus years ago with the Decca Bradford, but at that point I was getting old rental sets going for a quick buck to earn some cash. That was just done with replacement of panels and a polish. This will be the first time working on a TV set which is all valve and I need to fault find with fingers crossed the LOPT and CRT is fine.
But today is another day, well after sleep it is.
Adrian
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