This 80's circuit can be implemented with modern equivalent FETs with lower on resistance. The attenuation is 80 dB at 100MHz.
This is an old test circuit for integrated TTL counters, feeding a Nixie tube, common at the time....
This traditional crystal radio circuit, but which has a modern version with diode, was found in an...
This headphone amplifier using a pickup coil can be used as an extension for devices such as TVs,...