We found this circuit in the March 1980 Radio Electronics magazine. The circuit used is the HA2400 released at the time. The power supply must be symmetrical.
This receiver for listening to the TR-23 phone was manufactured in Japan in the 1960s. The circuit is...
The two previous circuits show the INA185 a current sensing amplifier in basic applications. This...
This small digital transmitter uses a 1 MHz crystal, or another nearby frequency, to produce a...