Found in 90s Radio Electronics, this circuit is intended for amplifying analog video signals. Integrated circuits are uncommon today and the bandwidth is 100 MHz.
The basis of this circuit is a CA3130 operational amplifier. The transistor can be BC548, and the...
This circuit, found in a 73 magazine for radio amateurs, is used in radio localization. The...
This circuit is from an American magazine Popular Electronics of March 1991. The circuit produces both...