This circuit was found in the 1992 Radio Electronics Handbook. It is used to test VCR recording heads. It can also be used for other purposes.
In this amplifier, the supply voltage is 35 V and the input resistance is 2k2. Equivalent...
This high speed laser diode driver was found in a 1980s documentation. Power FETs can be replaced...
This instrumentation amplifier with differential inputs was found in documentation from the 90s....