This circuit allows you to read resistors up to 20 M ohms, converting it into voltage. The circuit is from the 90s. The operational ones used admit modern equivalents.
This amplifier was found in a Japanese publication in 1972. Transistors are uncommon today, and...
The current of this source is 200 mA at the most, and the output depends on the zener that may...
Found in Mallory documentation from 1968 this circuit uses an integrated circuit from that time. The...