TTL Counter (CB21360E)

This counter from 0 to 9999 was found in English documentation. The power source must be 5V with at least 1A.

Varicap Spy Transmitter (CB19433E)
This circuit with variable capacitance diode (varicap) is from a publication from the 90s. The...
Divider by N with the 4017 (2) (CB12131E)
With this circuit it is possible to divide the frequency of a rectangular signal by values between 2...
Triac driver (CB22446E)
The presented circuit uses an optocoupler to trigger a triac. We found it in a Popular Electronics from...