Current to voltage converter (CB7332E)

This circuit is from a Popular Electronics from the 90s. The integrated circuit admits equivalents that must be tested.

Variable Frequency Oscillator (CB22465E)
This VFO circuit generates signals from 2 Hz to 50 Hz. We found it in Popular Electronics from...
Varicap Voltage Controlled Oscillator (CB13347E)
We found this circuit in an old documentation from the 70s. The circuit can use any varicap and...
Photo Field Relay (CB18344E)
This intermittent circuit, found in a 1967 documentation from Japan, generates magnetic pulses when...