This amplifier was found in a 70s documentation. The product gain x bandwidth is 350 MHz. The integrated circuit is from that time, uncommon today.
This 1950's circuit used one of the first commercial transistors and had two stages for audio...
Using integrated circuits from the time, we found this audio compressor in an English publication from...
This is an experimental crystal radio that uses no power source. The antenna must be very long (at...