Using the NE5205 integrated circuit this circuit was found in the May 1987 issue of Radio Electronics magazine. It can amplify signals up to 450MHz.
This circuit was originally created to monitor signals from a remote-control transmitter for the...
In this circuit the CA3140, an operational amplifier, is used as a comparator with the zener diode...
This circuit was found in old documentation. The frequency depends on R1 and C1. For the...