This circuit, found in 1993 documentation, is the traditional relaxation oscillator configuration with unijunction transistor. The frequency depends on C and the resistance value R.
This circuit generates an FM signal of 4.7 or 10.7 MHz for audio signals on analog TV or FM, with...
This simple test for general purpose NPN and PNP transistors was found in a 1974 publication....
This circuit from a Radio Electronics magazine from June 1969 already shows the use of the newly...