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:

Tube Type Function
V1 12BE6 Converter
V2 12BA6 CW osc/IF amplifier
V3 12AV6 2nd Det/1st audio/AVC
V4 50C5 Audio output
V5 35Z5 Rectifier

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.

©1995-2017 Philip I. Nelson, all rights reserved