Found in a 1964 Electrronic Design, this circuit is intended to control analog video signals. The circuit has an attenuation of 45 dB at 20 kHz.
In the figure we have a Texas Instruments circuit for TTL interfacing using discrete transistors. The two...
This circuit was found in Radio Electronics magazine from June 1963. The range is small and the...
The project presented in a 2009 documentation is intended for radio amateurs operating in the...