This circuit is from a 1969 EEE magazine. The transistors are from that time, but the circuit can be implemented with modern equivalents, such as 2N2646 for Q3.
We found this receiver on a single chip in the 1976 Siemens integrated circuits manual. The...
Found in Radio Electronics from the 90s, this circuit has several outputs with different pulse...
We found this circuit in an English publication from the 60's. The transistors are of germanium of the...