Circuit Project Electronic

The RF oscillator using the inverter N2 and 10.7Mhz ceramic filter is driving the parallel combination of N4 to N6 through N3.Since these inverters are in parallel the output impedance will be low so that it can directly drive an aerial of 1/4th wavelength. Since the output of N4-N6 is square wave there will be [...]

Feautures:
* automatic switch on on rear gear
* led-bargraph display
* audible bleep on last led
* “good old” design style, no microcontrollers!
This was one of my first designs: it is an ultrasonic parking sonar.
Based on an ultrasonic amplifier from an article seen on a 1982 magazine, it was once installed on the rear bumper of my Volvo [...]

This is a simple circuit for an electronic switch - I’d designed this for an external footswitch module but also with a duplicate button panel mounted. There are enough gates spare to easily [...]