1958 Sony TFM-151
Portable radio, thermoplastic cabinet
9 5/16 x 7 5/16 x 3 1/16 inches / 237 x 186 x 78 mm
Fifteen transistors (Sony, 3x 2T65, 2x 2T76, 2x 2T85, 5x 2T201, 3x 2T203), + four Sony 1T23 diodes and one Sony 1T51 varistor)
AM superheterodyne circuit / FM circuit
Four 1.5-volt "D" cells
Manufactured by Sony Corp., Japan
The world's first AM/FM transistor radio. Fifteen transistors! And of course none of them were "dummy" transistors — all were fully employed, eight of them in the FM circuit alone. An extremely expensive radio at the time, and very few units appear to have been produced before production was halted — as Alan Kastner has suggested, perhaps not many more than 1000 units in total were produced.