National Panasonic RQ-237

The RQ-237 was an AM/FM Radio Cassette Recorder manufactured by the National Panasonic Corporation of Japan in 1974. These radio cassettes were also available in RQ-237S, RQ-237SE, and RQ-237JS versions, in either black plastic finish or wood grain effect. The RQ-237JS version had shortwave and mediumwave bands only. These units were a compact size with dimensions 11 3/8-inches × 7½-inches × 3 1/8-inches, and mass 5 1/4 lbs. The photographs and descriptions in this article are for the RQ-237S, which has AM and FM bands.

According to my service manual, the RQ-237JS version had an M5115P integrated circuit (IC), which drove a transformer to produce 2-watts audio output. Interestingly, pins 1, 17, and 16, connects directly to an audio output transformer with a centre tap. This indicates that the audio IC performs the phase splitting internally, which is a very elegant electronic solution.

At the top, there is a selector switch for tape, radio, and sleep functions. There are also tone and volume controls. At the back, it has an AM/FM selector switch, AFC switch, and a voltage selector switch. On the side, it has the following sockets and switches.

• Microphone and Remote Sockets
• Aux In
• MPX Out
• Sound Monitor Switch
• External Speaker Jack Socket
• 9 V DC in Barrel Socket

In the following pages of this multi-page article, you can see the different aspects of electronic and engineering design of this very rare radio cassette recorder.

Cost/eBay

These were high-end machines with excellent radio reception and sound quality. They were hand assembled and consequently highly collectable today due to the good electronic engineering inside. This unit has brushed aluminium finish at the top and sides, which looks wonderful if the unit is in mint condition, however scratches can lower its value considerably. One in fair condition might sell for around ten pounds; however, one in mint condition can go for considerably more money.

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