This simple neon lamp oscillator produces a 140 Hz, 40 V peak-to-peak signal. The frequency is given by the capacitor that can have its value changed. Note the high supply voltage.
This photoelectric circuit from a 1960 publication uses a 6.3 V electromechanical counter, common at...
We found this circuit in a magazine 73 from the 90's. It is a circuit indicated for radio-amateur...
) This circuit uses two 4046 CMOS PLLs to produce a modulated signal of good intensity. The MOSFET can...