This circuit also detects IR, providing LED indication. The circuit is used to indicate humidity in bench tests. We found it in the Radio Electronics magazine of February 1990.
This circuit can also operate with SW and even VHF signals up to 150 MHz. The circuit can be...
This circuit is from a 1976 publication and can be assembled with more modern operational...
This 80's Motorola circuit can generate 100 MHz signals, but they can reach 200 MHz with the...