A question or two for Philco enthisiasts.

[toxcrusadr]

Most of the small value caps used in radio circuits (other than the electrolytics) can be purchased in 600 V rating for about the same price as 250 V or 400V. 250 will not be high enough for all of them, 400 will probably cover 90% of them (a few places in some circuits see 450 or 500V such as at startup), but 600 is safe anywhere. So if you can't figure it out just use 600V caps and you'll be fine. Or if you can relocate that website you mentioned...

Re: TV capatibility, the idea was that early TVs could be made without an audio amp or speaker, and would feed their signal to the radio through that jack similar to a turntable. The very expensive new TV technology could be made cheaper and a little more accessible that way.