Sanyo M-GR60

The M GR60 (also written M-GR60 and MGR60) was an AM/FM stereo radio cassette player manufactured by the Sanyo Corporation in Singapore. It has the following features and specifications.

• AM, FM, and FM Stereo switch positions
• Manual variable capacitor tuning
• Radio/Tape selector switch
• Fast-forward, play, and stop controls
• DC power socket
• 4.5 V system using 3 × AA batteries
• Power Output: 25 mW per channel
• Headphones: 32 Ω
• Dimensions: 87.0 mm × 145.0 mm × 36.5 mm
• Mass: 310 g

Review

This Sanyo unit is of course for the budget end of the market, but even, so these old cassette players were so well manufactured that they continue to operate with minimal loss of performance. This is of course extremely good legacy for the Sanyo Corporation. In this design there is a metal tape transport mechanism (TTM) chassis and a metal pushbutton selector which makes the unit heavy and robust. Since it does not have auto-reverse or rewind functions, the TTM is extremely simple with one belt from the motor turning the capstan flywheel, and another belt from the flywheel pulley turning the tape winding spindle. The drive belts are under the PCB, hence you will need to desolder some wires in order to turn it over. It’s not a difficult job and an engineer or an experienced hobbyist ought to be able to carry it out without too much fuss.

The audio amplifier IC is LA4520 by the Sanyo Corporation, which has built-in stereo preamplifiers and power amplifiers. The TTM is driven by a single DC motor with C1470 IC providing the speed regulation function. This combination of chipset was widely used in cassette players of that time. In addition, I also spotted a BA1360, and BA4232AL, by the ROHM Corporation. The radio circuitry is a good design and reception is very good. The tuning is manual by way of a variable capacitor, and they have even provided a dial and a needle that moves via a tuning string mechanism.

The sound quality is very good, but it all depends upon the quality of your headphones that you use with it. Stock headphones that come with budget-end cassette players are usually not so good, and there is room for improving the sound with modern headphones. The unit I managed to find was in very good condition and showed virtually no signs of wear on the head or mechanism, and it sounded very good too. Remember that this unit is a 4.5-V system and requires three AA size batteries in the compartment. It is from a time before volume limiter systems became the norm, and consequently it can be very loud.

Price/eBay

This is a very simple budget-end unit that would have been mass-produced, so they are not worth much. A broken unit on its own with scratches would cost around five to ten pounds, however a unit in mint condition, with a lovely shiny cassette lid, and in its original packaging, would be collectable and worth much more. A red coloured one, which is not seen often, would of course be even more desirable for a collector. In the following pages of this multi-page article you can see the inside electronics, and mechanical engineering.

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