Circuit Project Electronic

This circuit simulates a chime similar to the sound many cars make when the keys are left in the ignition. The bottom two gates form a squarewave audio oscillator that drives the base of the 2N4401, turning it on and off at an audio rate. The top two gates produce a short low-going pulse about [...]

Here is a simple circuit for generating over 100 volts from a 12 volt source for powering low current devices and experiments. The two transistors may be 2N4401 and 2N4403 or similar for lower power applications or higher power devices for heavier loads. If more power is desired then lower the two 10 ohm emitter [...]

Wireless portable unit
Adaptable with most internal combustion engine vehicles
Parts:
R1,R2,R19_______1K 1/4W Resistors
R3-R6,R13,R17_100K 1/4W Resistors
R7,R15__________1M 1/4W Resistors
R8_____________50K 1/2W Trimmer Cermet
R9____________470R 1/4W Resistor
R10___________470K 1/4W Resistor
R11___________100K 1/2W Trimmer Cermet (see notes)
R12___________220K 1/4W Resistor (see notes)
R14,R16________68K 1/4W Resistors
R18____________22K 1/4W Resistor
R20___________150R [...]