This circuit with an unusual configuration was found in the January 1974 issue of Radio Electronics magazine. The frequency is given by L1/C1, and the transistors admit equivalents.
This circuit for a 16-channel infrared transmitter was found in the August 1984 issue of Radio...
We found this circuit loader in a French magazine Electronique Radio Plans from July 1993. The...
This charger is from an old publication of 1975. The PNP transistor can be the BC558 and the NPN...