[BC] 110 V DC AC/DC radios 5 tube all american

[WFIFeng@aol.com]

In a message dated 12/03/2006 8:29:46 PM Eastern Standard Time, 
mail at radiolanes.com writes:

> The tube type Seeburg jukeboxes had a relay that kept the B+ off in standby
>  mode while keeping the filaments on. In the case on the "instant on" TV, a
>  way to sell more tubes??

In all of the "instant-on" TV's I'd seen, the diode kept the filaments at 
approximately 50%. (It was a half-wave rectifier, unfiltered, thus ~ 50% power 
thru the filaments.) This would actually *prolong* the life of the tubes, since 
they would not be coming up to full temp after sitting at room temp. They were 
already at least 50%, and came-up very quickly to full temp when the power 
switch shorted that diode and connected the B+ power supply. It wasn't truly 
"instant" on, but it was close. A couple seconds, as opposed to 20-30.

With solid state sets, of course, that's a true "instant on", and most of 
these keep the CRT filament operating at reduced volatge when "off", full voltage 
when "on".

Willie...