We found this circuit in an English publication from 1969. The circuit uses transistors from the time and can operate at frequencies up to 300 MHz. Observe the waveforms of the obtained signal.
The transistors are 2N918, 2N3464 and other RF equivalents of the time for Q1. For Q2, 2N3399, 2N2894...
This circuit, which can be used as a shield, was found in a 90s Electronic Design. The circuit...
This interesting intercom circuit was obtained from an Argentine publication from the 1970s....