We found this circuit for receiving shortwave on a mediumwave radio in a 1986 Hobbyst Electronics PE. The circuit has the received band given by T1 which can be an FM IF.
This circuit is suggested by Texas Instruments in his Optoelectronics Sourcebook. The transistors...
This circuit was found in an English documentation from the 90s. It uses a PLL CMOS 4046 and is...
The circuit is from an old documentation making use of an operational amplifier of the time. The...