This audio level indicator was found in October 1980 Radio Electronics magazine. See the table with the dB values of the indicated signals.
This micro-transmitter for the 27 MHz band was found in a 1976 technical documentation. The...
This passive circuit was found in the March 1995 issue of Elexctonics Now magazine. The circuit is for...
I found this circuit in an old English magazine from 1979, but it can be easily assembled with...