KDKA AM Pocket Radio

On the weekend I got this pocket AM radio from a Saint Vincent DePaul thrift store for 99 cents. My guess is it was a free giveaway at the Pirates' stadium, one of those "First 1000 fans at the game get a free AM headphone radio!" game nights. Add a little beer sponsorship to help cover the costs and it made a nice little gift to get people out to PNC park.

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The radio is mono headphone only, no speaker. This was a surprise, since most pocket radios that look like this have speakers! In a way this is good, most listeners at a game would be listening on a headphone anyway to be able to hear play-by-play over the crowd, and it also saves battery power by having a lower power audio amp. The case is just molded plastic with no trimmings or textures.

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It looks like a simple and traditional superheterodyne, a classic circuit in all kinds of radios, and the detector appears to be a silicon diode, not germanium which is the better choice for a detector, with lower distortion. The ferrite bar in the loopstick antenna is not the smallest I've seen.

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The board is marked "TS 314". The tuner is on the top, tuning radio stations from 540 to 1600 khz. Circuit board is the usual phenolic, power is 3 volts from 2 AA cells. Vintage is unknown, and a friend thought it could be from the 1980s.

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KDKA is the flagship station of the Pittsburgh Pirates and operates at 50,000 watts at 1020 on the AM dial.