Found in a 1924 Gernsback publication this circuit uses 4 batteries for power and loop antenna. Listening is over a high-impedance type earphone or loudspeaker common at the time.
We found this circuit in a 1965 General Electric documentation. The circuit generates synchronized...
Found in a 1968 Ferranti documentation, this circuit can be implemented with modern equivalent...
This circuit with the ULN3784B appeared in the October 1984 issue of Radio Electronics magazine. It can...