Thanks for that Steve/ Trevor. I was trying to get this sorted/definitively ID'd so there is an agreed way forward but it might be more difficult than I imagined. Should the OP use an Isolating Tr for example, if it's the 146 with the round hole? I very much hope that my attempt to explain things hasn't made it worse for the him
. He's very determined to restore the set though and doesn't intend to rush in too much.
You may come through as an expert on Tr's or the lack of them in the end Michael and it will do you no harm, although there is always an option to start with something simpler. I think looking at PSU diagrams and ID'ng components at the "power up end" plus basic theory, will be a good start with no voltage required
I meant to mention the Frank Murphy Biography "A First Class job" written by his daughter Joan Long. His personal story was quite sad in the end and not unlike that of J L Baird-especially re the business experience/betrayal. Very popular with his students when he died in Canada at a relatively early age.
Dave