Bilateral current source 2 (CB20819E)

We found this circuit in an American publication from the 1980s. Equivalent modern operational amplifiers can be used.

Sensitive Field Strength Meter (CB14900E)
This sensitive field strength meter was found in 1993 documentation. The instrument may be the...
Driver for Nixie Tube (CB6682E)
This circuit was found in a 1967 General Electric manual. It is intended for the control of high...
Variable output for the 7812 IC (CB24825E)
The figure shows how to vary the output voltage of a 7812 regulator between 12 V and 2 V less than...