Sony TR-3550

The TR-3550 is a solid-state pocket AM radio manufactured in Hong Kong by the Sony Corporation in approximately1976. It is a six transistor heterodyne receiver, which operates on a pair of "AA" size dry cells. It has coverage of 530–1605 kHz in the medium wave (MW) band.

Compared to some of the mass produced radios coming out of China, this one had a Japanese designed circuit with high specification silicon transistors, and consequently it could operate for a much longer period on a pair of batteries providing only 3 V.

The 5.7 cm diameter loudspeaker provides a much better bass due to the plastic enclosure and grille, and consequently the sound is much better quality compared to cheaper radios. The circuitry employs six silicon transistors in a TO-92 plastic package, and one of them is a BC238A, whilst the others appear to be unmarked. The manufacturer of the variable capacitor is TOKO INC.

This particular one has a brushed aluminium finish; however, there were versions that were red and cream.

Cost / eBay

This was a mass produced item and sold all over the world. It was extremely popular in Canada and Europe, and there were many versions in different colours. There should be plenty of these radios in mint condition still available, and on the right day, could fetch a packet on eBay.

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