This circuit was found in an Electronic Design from 1964. The components are from that time and can be replaced by equivalents. The modulation ranges from 0.25 to 0.75 of the 20 kHz pulses.
This circuit is suitable for SSB modulation and was obtained from an amateur radio documentation from...
This circuit was obtained in a 90’s Popular Electronics. The operators admit equivalents such as...
This 7400 TTL circuit has a memory, keeping the LED on when a pulse is detected. The circuit must be...