National SW-54 Communications Receiver (1955)
National's model SW-54 was a very popular entry-level communications radio during the 1950s. It was
made from 1950-1957. Priced at $50-$60, it was directly competitive with the
also-popular Hallicrafters S-38, which went through several variations
between 1946 and 1961.
The SW-54 is a five-tube AC/DC type receiver, covering the frequencies .54-30 Mhz in four bands.
It offers CW as well as AM mode (although no BFO). Audio is supplied through either the built-in speaker
or headphones. The controls are simple and clearly marked, appropriate for this type of radio.
The first two photos show the SW-54 in its metal, hammertone-painted cabinet.
The SW-54 cabinet is all metal and consists of three pieces, the main cabinet, a removable back,
and removable bottom. The removable bottom allows you to do most service operations without removing
the chassis from the main cabinet.
The next two photos show the chassis. National took the trouble to copper-plate the chassis,
making it very attractive when cleaned up.
Clearly visible in the first chassis photo is the large fine-tuning dial. It is simply a wide, flat
dial mounted on the same shaft as the smaller tuning knob. This inexpensive direct-drive arrangement does
improve one's ability to do fine tuning, although it's not as effective as a
bandspread tuner, which uses a separate variable capacitor.
Here is the tube lineup:
||CW osc/IF amplifier
||2nd Det/1st audio/AVC
The last photo shows the underside of the chassis before restoration.
Restoring the electronics was a simple matter of cleaning the controls and replacing capacitors.
As found, the radio made a loud hum, a sure sign of bad
filter capacitors. If you look at the chassis underside photo, you'll see
a large yellow electrolytic capacitor near the right. When the original filter
capacitor failed, someone attempted to fix it by soldering this replacement
in parallel. That was a mistake. You should always remove the old capacitor
completely from the circuit. Otherwise, when it inevitably fails, you will
have to repeat the repair.
This radio was stored in an unheated garage for years. Its painted cabinet had quite a bit of
surface rust when I bought it, a factor that contributed to the low price! At first glance, you
would have sworn there was no hope for the cabinet, short of stripping and repainting it.
I knew from experience that Naval Jelly can work wonders to remove such rust, however,
and that proved to be the case. It took patience and several applications of Naval Jelly,
but the rust eventually disappeared completely, leaving only very slight paint blemishes
that were easy to polish away.
After alignment, this radio proved to be a great little performer, and very easy to
use. SW-54s are still quite plentiful, so if you're looking for an inexpensive
shortwave radio, and one that's easy to work on, this is a great choice.
Like all AC/DC type radios, this one can present a shock hazard
if you poke your fingers inside. The back cover completely
encloses the chassis, and the plastic knobs insulate you
from any danger in normal operation. You should not operate
the radio with its knobs removed.
After owning this radio for a few years, I gave it to my
brother as a little treat.
I own one other National receiver, a model NC-60,
which is the successor to this one, dated 1959.