This circuit uses a resonant reed relay to recognize the frequency of an input signal. Adaptations can be made to obtain functioning as a shield. The circuit is from 1965 documentation.
This circuit was found in the August 1997 Electronics Now magazine. The circuit uses well-known...
With this circuit, a single antenna can be used to receive TV and FM signals (VHF), separating them for...
The circuit shown has the component values calculated for a frequency of 1 kHz. TL064 can also be...