Early 1970's RCA portable.

[zeno]

Mystery solved.
This chassis is very different than the other CTC53.
All the Sams I have #s' 1201, 1271 & 1452 are nearly
the same. This one is different in the tube compliment,
filament circuit & it has a HV reg tube for starters.
Enuf IMHO to give it its own CTC series. I would guess
its an export only rig so they just put it in the CTC53
family since its "close". Shows why beyond general discussions
you need very complete info on chassis & model.

73 Zeno

[zeno]

Originally Posted by Jon A.

I was going to eventually ask how to defeat it in my flatty, but best to leave it alone I guess.

It involves moving one wire BUT every time you open up
a set you risk an accident. Just like surgery, always some risk.
A knew a girl in HS that went in for wisdom teeth & came
out DEAD..........
BTW the Zeniths & prob. others did it like this.
A filament transformer kept the CRT at low voltage. Its
secondary was in series with a winding on the main power
transformer so when you powered up the voltages added up
for full filaments. Cheap & simple, the way TV's should be.

73 Zeno

[DavGoodlin]

I had one of those Westinghouse 19" BW sets, a 1963 attache' model, that was instant on.
I also have a 19" Westinghouse color, 1968 model, also instant on AND has a defeat switch on the back, like your RCA, that "unhooks" rectiifer diode mentioned below.

There is a two-gang on-off switch. One side switches power to the solid-state LV rectifiers, the other side had a rectifier diode across it and switches the series-wired heater string (and CRT filament transformer on the color set) such that when the set was off, only 1/2 cycle of AC is applied to tube heaters, keeping them kind of hot and significantly reducing warm-up time.

BTW - I removed this feature on both sets.

[Phil R]

Thanks for the information Zeno!