Early Model
Early Model
The Crosley 51 is a two tube regenerative that was built in 1924 by Powell Crosley in Cincinnatti. The '51 is the most common version of a series of radios that Crosley produced in 1924. The 51 uses a spiderweb coil for tuning and a sliding spiderweb for the tickler regeneration. The receiver is tuned with a book capacitor which is wired in series with the antenna. A long antenna should be used on this receiver in order to reach the low end of the band. This radio uses the capacitance of the antenna to help tune this radio. It is designed for high impedance headphone use.
The schematic of the 51 is available here.
Common (later) version