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An RCA 140
#23

Well OK, but the output transformer is also a big offender. The whole set was so crammed into that chassis, that it appears that the output transformer was somewhat inadequate, especially sincw the operating conditions of the 53 were such that it could belch out 10 watts. In those few years, RCA was riding high, with their high power audio, but it was mostly, if not all, class B. If you opened the volume up all the way, you'd get lots of sound, but it was lousy (class B) sound.

The interstage transformer is a DRIVER transformer, so you'll notice on the schematic that the secondary DC resistance is lower than the primary resistance. The 56 is pushing a class B amplifier, and the grids do draw current.


Messages In This Thread
An RCA 140 - by exray - 09-28-2010, 08:41 PM
Re: An RCA 140 - by exray - 09-28-2010, 08:46 PM
Re: An RCA 140 - by Ron Ramirez - 09-28-2010, 08:58 PM
Re: An RCA 140 - by exray - 09-28-2010, 09:37 PM
Re: An RCA 140 - by Alan Douglas - 09-29-2010, 06:34 PM
Re: An RCA 140 - by denver - 09-29-2010, 07:53 PM
Re: An RCA 140 - by Jayce - 09-29-2010, 11:17 PM
Re: An RCA 140 - by exray - 09-30-2010, 09:46 PM
Re: An RCA 140 - by Jayce - 10-02-2010, 09:07 PM
Re: An RCA 140 - by Ken G - 10-11-2010, 08:05 PM
Re: An RCA 140 - by Allen in SB - 10-17-2010, 12:51 AM
Re: An RCA 140 - by exray - 10-17-2010, 07:07 AM
Re: An RCA 140 - by Jayce - 10-17-2010, 05:15 PM
Re: An RCA 140 - by Doug Houston - 11-23-2010, 01:30 AM
Re: An RCA 140 - by Jayce - 11-23-2010, 06:06 PM
Re: An RCA 140 - by exray - 11-24-2010, 08:19 AM
Re: An RCA 140 - by Jayce - 11-29-2010, 06:27 PM
Re: An RCA 140 - by FStephenMasek - 12-01-2010, 11:48 PM
Re: An RCA 140 - by Jayce - 12-02-2010, 03:38 PM
Re: An RCA 140 - by exray - 12-02-2010, 04:40 PM
Re: An RCA 140 - by Ron Ramirez - 12-03-2010, 12:18 AM
Re: An RCA 140 - by TA Forbes - 12-09-2010, 09:07 PM
Re: An RCA 140 - by Doug Houston - 01-01-2011, 08:44 PM
Re: An RCA 140 - by theboyzz - 01-29-2011, 12:14 AM



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