This receiver was found in a Japanese publication in 1967. The circuit uses germanium transistors and details of the coils are not given. Power is supplied by a 9 V battery.
This circuit indicates when the voltage of a 12 V battery is low. With changes, for example, the...
If mounted with SMD components, this transmitter will be so small that it can be installed inside a...
This circuit generates some very interesting tone forms having been found in an American...