We found the circuit of this Japanese transistorized commercial receiver in a documentation from the 1960s. It is a radio for the medium wave range with 6 transistors and 9 V power.
This low-power intercom can be powered by solar cells. The circuit is two-way, with an integrated of the...
Reversing the switching action, with the output going high when the input is low, can be done by...
This converter was found in the June 1991 issue of Radio Electronics magazine. The circuit uses...