Simple photometer (CB20507E)

This 3-component circuit uses an analog indicator. We found it in an old publication.

Varicap Frequency doubler with (CB4107E)
We find this circuit in American documentation from the 1980s. It consists of a frequency folder...
Flip Flop with the Operational LM3900 (CB4510E)
Other series amplifiers such as the MC3301, MC3401 and LM2900 can be used on this circuit. We...
Divide-by-5 Using the 4018 (NI005E)
One pulse in the output is produce at each 5 pulses applied to the input. The circuit uses CMOS...