ESPY tv Kit on Ebay

[polaraman]

Says it is from the 40's.

polaraman

http://cgi.ebay.com/RARE-1940s-Espey...QQcmdZViewItem

[David Roper]

You bet it is, 1947 to be exact. It was some time ago that I was studying the schematic in an early volume of Rider. The HV supply is quite unusual in that it utilizes a 5Y3GT as rectifier which somehow manages to supply adequate voltage to the CRT anode; I must confess I didn't understand how this could be done without far exceeding that tube's maximum operating voltage and would welcome an explanation. A second 5Y3GT supplies B+ and the rest of the tubes are miniature 7-pinners, easily making it the earliest set with such a mini majority.

This is Radiolaguy Sonny Clutter's Espey, restored and using the standard-issue 3KP1.

[tubesrule]

I have an original assembly manual for the Espey and it shows the HV supply at 1000V. Still this would exceed the 1400V PIV rating of the 5Y3, so they may have just been going on luck here.

Darryl

[Bobby Brady]

Wow!
That is really neat!
Why is it green? Was that color intentional or just the color of cheap phosphers or maybe it is an oscillascope tube?

[David Roper]

P1 = green. A white phosphor tube (P4) was indeed more expensive than green.

[Sandy G]

Back then, I'd imagine they were happy that they actually had a "TELEVISION" to watch...Wow... A Radio w/Pictures !! Can you imagine...What'll they think of next...