This 3-valve receiver was found in a publication by Edelman from 1924. The circuit has two supply voltages, B being 60 to 90 V.
Found in a publication for radio amateurs from the 1990s, this circuit makes it possible to...
I found this circuit in a Popular Electronics from November 1999. The magazine is no longer...
This simple transistorized receiver with earphone was found in a Japanese publication from the...