1954? Koyo Parrot KR-4S1 (1956 example)
Small coat pocket radio, thermoplastic cabinet
5 1/8 x 3 3/8 x 1 9/16 inches / 130 x 86 x 40 mm
Four subminiature tubes (1AG4, 1AG5, 1AH4, 1V6), superheterodyne circuit
One 45-volt "B" battery, one 1.5-volt "A" cell
Manufactured by Koyo Denki Co. Ltd.; Tokyo
A wonderful little Japanese subminiature tube radio, much smaller than many 1950s transistor radio coat pocket sets. It may also pre-date many of those transistor sets — several sources date this radio's initial production or distribution to 1954, though I haven't yet found any information to make that date solid. The example shown here, for instance, was assembled in late 1956 — so for the meantime, I'll leave the 1954 initial production date here with a question mark....