Silvertone Model 4587A Tuning Indicator

Radio dial with three bands and user-installed station identifiers around the edge.

My friend Jim Carstensen restores old radios as a hobby. His latest project is one that belonged to his father-in-law’s father. It was made by Sears in the 1930s. He hasn’t yet begun restoring the beautiful wood console, but he has the internals nearly finished, and I was fascinated by his description of one particularly “high tech” feature. The dial of the radio includes lighted placards to indicate the call letters of favorite stations. The call letters were inserted by the user, under clips around the dial.  As the dial is turned, it rotates an arm that presses a switch against a toothed wheel. by bending up metal tabs along this wheel, the user selects locations that turn on a lightbulb to illuminate the call sign. It’s the analog precursor to digital tuning!

Bending up the tabs on top of the toothed wheel causes the station identifier to light.

This degree of user customization is particularly impressive when you consider there are many spots in this chassis that run at 300 volts!

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