Next year marks the fiftieth anniversary of the transistor radio, which, like the diminutive electronic component it’s named for, was invented in America. Using smaller solid-state devices in place of vacuum tubes, transistor radios could be scaled down considerably, yet the earliest versions sold for sums well out of proportion to their size. Most cost between $50 and $90 at a time when a new car could be had for less than $3,000.

Marketers banked on the portability of the new sets, and the first one from Japan was billed as a shirt-pocket radio when it arrived here in 1957. Sony tried to disguise the fact that the TR-63 was a bit larger than advertised by giving salesmen shirts with oversized pockets expressly tailored for the product.

The most collectible models, from 1963 and earlier, can often be identified by the triangles at 640 and 1240 kHz on their dials. Based on the civil-defense emblem, these symbols indicated the two frequencies that were to be used for emergency broadcasts in the event of a Soviet attack.

Factories here and abroad produced millions of transistor radios, with brand names from Admiral to Zephyr. Many wore stylish cases emblazoned with modern decorative motifs that included sweptback wings, stars, and, as if to remind people of the significance of those little triangles, atoms.

Prices have fallen in recent years, so this could be an opportune time to begin acquiring transistor radios. “I sold a radio on eBay not long ago for about $40 that would once have gone for $200 to $300,” reports Darryl Rehr, a Los Angeles aficionado who has several sets displayed in his office. These days, Rehr notes, $100 should buy something genuinely collectible. Rehr also says that the look of a transistor radio is more important to collectors than whether it works, so select visually interesting examples and be sure to examine their cases for cracks and other imperfections.

One rarity to watch for combines the world’s first transistor radio, the Regency TR-1, with a presentation case resembling a leather-bound copy of Jules Verne’s Around the World in Eighty Days . The producer Michael Todd had a few of these made as gifts to celebrate his film version of the novel, and back when bidding was turned up to high volume, the package was valued at upward of $4,000.

— David Lander