Re: My first telly TV22
How rusty are the laminations?
This can effect the line output transformer enough to cause problems with a self oscillating stage.
A good ECL80 is more important than a good PL81.
Note that once the transformer has failed such as to prevent oscillation, then the PL81 will be biased fully on and this will quickly kill the valve and further damage the transformer.
If you are very lucky then the fault is something simple like failure of one of the two 2uF capacitors, such as the one on the scan coils.
If you find the top deck valves glowing brightly, but some of the rf valves cold, then one of the heater decoupling capacitors on the RF deck has gone short, you can just snip one end as a temporary fix. For some reason this fault sometimes also stops the line time base working.
Have to stop there for the school run!
Cheers
Andy
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