Simple photometer (CB20507E)

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

Solar intercom (CB20503E)
This circuit can be used in demonstrations or science fairs. The circuit uses headphones and can...
MRF1K50H 1500W Power RF Transistor (COM047E)
It can be obtained from Mouser Electronics the new 1,500 W RF high power transistor MRF1K50H fro m...
AC Millivoltmeter (CB4514E)
This alternating voltage voltmeter was found in a 1967 magazine. The magazine no longer exists, but...