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NO. 4550/4560 (Model 10B)

The Atwater Kent No. 4550 (& 4560) Model 10B Receiving Set was a minor but important revision in the celebrated three-dial breadboard series, introduced around 1924. Maintaining the core architecture of the Model 10A, this set featured the advanced five-tube Tuned Radio Frequency (TRF) circuit with two RF amplification stages, one detector, and two AF amplification stages, typically powered by four UV-201A tubes and one UV-200 detector tube. The key distinguishing feature of the Model 10B lay in its physical layout and operation: Atwater Kent engineers replaced the vertical mounting of the Model 10A with an orthogonal (sideways or horizontal) mounting of the RF coils. More significantly for the operator, the 10B added a three-point antenna tap switch on the first RF coil. 4550 Brown / 4560 Black. Board dimensions 31.5" x 10".

SCHEMATIC

4560 - Model 10B

4550 - Image Courtesy of Don Sturzenbecher

4550 - Image Courtesy of John Jenkins | Visit the SparkMuseum!

4560- Image Courtesy of Jeffrey Rehkopf