This simple bridge circuit can be used for impedance or resistance measurement using a high impedance earphone as an indicator. The circuit is from an American 80's documentation.
The MC33064 can also be used on this circuit of Motorola's 1993 Linear Interface ICs. The circuit...
The circuit shown is from National Semiconductor's Linear Applications Handbook published in 1994....
This converter for the 150 MHz band was found in an American documentation. Transistors are...