We found this circuit in the November 1995 Electronics Now magazine. The circuit is more accurate than the previous one using an external multimeter as an indicator.
This linear characteristic circuit is based on a junction field effect transistor. The FI and BFO...
This small transmitter of just 15 mW for the 3.5 MHz (80 meter) band was found in a 1986 Sylvania...
The time obtained in this circuit, from a 1978 publication, depends on R3 and C. R3 can have...