Found in the February 1990 Radio Electronics issue, this sophisticated 100 MHz probe uses a period display module. The circuit has an external power supply.
This circuit was obtained from a 1977 magazine, but can still be mounted using BC548 for TR1 and...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
The figure shows how to add a Darlington stage to an operational amplifier in order to obtain a...