1-Ttube reflex receiver (T1555E)

This one-tube circuit is equivalent to the previous one. We find it in a 1924 book by Gernsback, Power is made by batteries.

RF probe (CB21194E)
Found in a publication for radio amateurs from the 1990s, this circuit makes it possible to...
Sequential 4017 and Neon Lamp (CB10508E)
I found this circuit in a Popular Electronics from November 1999. The magazine is no longer...
3 to 12 MHz Receiver (CB18520E)
This simple transistorized receiver with earphone was found in a Japanese publication from the...