Found in a 90s Popular Electronics, this circuit can power a miniature railroad with voltages of 15 V and currents up to 1 A. The circuit has soft start effects.
For the 7 to 10 MHz band L1 is formed by 3 turns of 22 to 28 AWG wire in a ferrite core 15 to 20...
In the figure we have the way to simulate an SCR using two complementary general-purpose...
With this timer we can start between 30 seconds and one and a half seconds, time set in the pot....