NO. 4910, 4620 & 4375 (Model 12)

The Atwater Kent No. 4910 Model 12 Receiving Set was introduced in early 1924 and is recognized as one of the last and most powerful models in the iconic breadboard series. The Model 12 was a direct upgrade to the Model 10 series, characterized by the addition of another stage of audio amplification, resulting in a six-tube Tuned Radio Frequency (TRF) circuit. Its configuration was comprised of two RF amplification stages, one detector, and a three-stage Audio Frequency (AF) amplifier, typically utilizing six Type 01A tubes (or five 01A and one UV-200 detector). This substantial increase in audio power made the Model 12 the premier set for driving large, external horn speakers with impressive volume and fidelity for its time.

There were two earlier versions on the Model 12, part No. 4620, that was developed alongside the No. 4550 Model 10B (36" x 10"), and the part No. 4375, which was aligned to the No. 4340 Model 10 Radiodyne. This was simply a Model 12 Radiodyne that used the same coils at the No. 4340 Model 10 Radiodyne. These variants are exceedingly rare. The 4910 board measured 34" x 10".

Image Courtesy of Grant Kornberg, Technogallerie

Image Courtesy of Grant Kornberg, Technogallerie

Image Courtesy of Grant Kornberg, Technogallerie

Image Courtesy of John Jenkins | Visit the SparkMuseum!