1934 RCA Victor Model 120
This is 1934 RCA Victor Model 120 Superheterodyne Cathedral Radio. It is both
Standard Broadcast (540 kc to 1500 kc) and shortwave (1400 kc to 2800 kc).The receiver has
6 tubes and has features such as a dynamic loudspeaker, automatic volume control, single heater type
pentode output tube, continuously variable tone control and the inherent sensitivity, selectivity,
and tone quality of the superheterodyne.
||Rider's Manual Page #
||4-63 to 4-65
When received, the radio did play but it had some popping sounds and the volume
was not steady. However, there was no hum so the filter capacitors were good, and
upon inspection, they had been replaced sometime in the past. I replaced all of
the original wax paper capacitors and removed a shorting wire in the cathode
circuit of the audio output that someone had placed there.
The radio played OK then, but the popping sound upon power up was still there and
there was a buzz in the audio. I replaced the 2A5 audio output tube and the popping and
buzz are gone. After alignment, the radio still did not play correctly - there was distortion
in the audio and the sensitivity was not good and the sensitivity seemed to change from
bad to good over time.
I measured all of the resistors and found that the three 60k ohm resistors measured to
be 82k ohms - significantly out of tolerance. Also one 50k ohm resistor measured 68k.
In addition, two 10k ohm resistors measured quite low - 4k and 3 k ohms. Other resistors measured
within tolerance. I replaced all of the defective resistors and the radio plays well with
good sensitivity and no distortion.
Below is a picture of the underside of the chassis after I replaced the old
wax paper capacitors. Next to it is a pciture of the chassis top side.
Below is a picture of the back of the radio.
I think the radio did not have the original knobs when I received it. Below is
a picture of the radio with the knobs that came with the radio. Note that those
knobs do not match - one is different.
I replaced the bakelite knobs with replicated walnut knobs; knobs that were typical
of the 1930's era. The picture at the beginning of this page is the radio
with the new knobs.