The HR is a tuned-radio-frequency or TRF receiver with regeneration. Clapp-Eastham Company, the first radio parts company in the United States, first sold it in 1921.
The HR had a very compact design and used a UV-201, one amp tube.
The tuning range of 175-825 meters translates into 1713-363 kilohertz. Find out more about the history of the Clapp-Eastham Company by watching the mini-documentary on our YouTube channel.
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The Clapp-Eastham Company was the first radio parts company in the United States. The company was founded in 1906.
Two interesting details about the HZ's design are the knife switches on the control panel and the round transformers located underneath the tube sockets. The HZ was designed to use two UV-201, one amp tubes.
Clapp- Eastham built the HZ to be used with the company's HR receiver, which came out earlier. Find out more about the Clapp-Eastham Company by watching the mini-documentary on the museum's YouTube channel, just click on the link - https://www.youtube.com/watch?v=Zu0UVUok0Po