Found in 1980s Radio Electronics, this circuit triggers the ignition of a rocket after the countdown is completed. The countdown is monitored by the sequential lighting of LEDs
This circuit sensor is an NTC with a resistance of the order of 2k. The SCR can be from the TIC...
The load current can be adjusted up to about 1 A. The transistor can be TIP32 or TIP42. The...
This oscillator with common general-purpose transistors appeared in Radio Electronics magazine in...