Welcome!

This is a classic divider of frequency via two. It is achieved with a classic circuit T-flipFlop, round IC1 [ 4011 ]. In the circuit, the frequency of network, after are limit the negative half-s period of sine wave and transform in square wave, are divided via two. Thus for frequency50 HZ, we will take in the exit pulse of frequency 25 HZ. The supply of circuit it is + 5V and does not need high benefit in current.... [read more]

The piezoelectric element of a kitchen gas lighter is used in this simple, yet effective seismic detector. The piezo element must be placed vertically, one end solidly to ground.... [read more]

This is the voltage converter to get the voltage of ±1,25-30V from the input voltage of ±35V. I am using the 3 terminal voltage regulator for the voltage to be changed in this unit.... [read more]

This lovely circuit is a real gem! Easy to assemble and more sensitive than many commercial devices available.... [read more]

This circuit is intended for alerting purposes after a certain time is elapsed. It is suitable for table games requiring a fixed time to answer a question, or to move a piece etc. In this view it's a modern substitute for the old sandglass. Useful also for time control when children are brushing teeth (at least two minutes!), or in the kitchen, and so on.... [read more]

A Variable DC Power Supply is one of the most useful tools on the electronics hobbyist's workbench. This circuit is not an absolute novelty, but it's simple, reliable, "rugged" and short-proof, featuring variable voltage up to 24V and variable current limiting up to 2A. It's well suited to supply the circuits shown in this website. You can adapt it to your own requirements as explained in the notes below.... [read more]