A friend of mine has a early 50s philco b/w 21 inch tv that he has just aquiried . Anyhow it has two selenium rectifiers in it . Is there any specific diode used to replace these or are there different replacements according to application .

1N4007 pretty much works for most replacements of selenium rectifiers in power supplies. You might need to put something like a 30 ohm resistor in series with the output since selenium stacks have a significant voltage drop.

John Y.

What he said. Thats what I did to my '53 Philco that had the two selenium rectifiers. Is your friend's TV one of those split chassis units? If so, its probably the same type of set I recently restored. I can send him the schematics if he needs them.

i will find out this weekend, he is bringing it over