850's Classic Backup Transmitter

The R.C.A. BTA-1R Transmitter, in the classic colors. It uses 4 ea. 4-400A tubes; two as modulators and two for the R.F. output stage.

For this station, it only needs to produce 500 watts day and 250 watts night.

Remember the days when transmitters used the cotton-covered wiring ? The resistors snapped into huge clips, and the Plate Ammeter was always dusty because it was behind two panes of glass? Welcome to the days of yesteryear, when transmitters weren't built to be remote controlled.

There is nothing quite like the glow of a properly biased modulator tube. The new cadre of broadcast engineers will likely never see such a sight....

(For which they may be grateful...)

The Modulators are on the left, and the R.F. finals are on the right. The P.C. boards above the modulators are part of an audio feedback circuit.
One of the plate mulitpliers (see Little Blue Arc) is above the right R.F. Output tube.

Copyright 2005 by Vital Sounds - ALL RIGHTS RESERVED