Random circuits

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Dicing With LED's

Every self-respecting DIYer makes his own electronic dice with LEDs as spots. Then you don’t have to throw the dice anymore – just push the button. The electronics also ensures that nobody can try to improve his luck by fiddling with the dice. Too bad for sore losers! This circuit proves that an electronic die built using standard components can be made quite compact. The key component of here is a type 4060 digital counter (IC1).... [read more]

Minimalist Oscilloscope

If you are the proud owner of an old oscilloscope tube, you may be interested in using it once more for its original purpose. All you need are the right voltages on the right pins: in practice you may need to peer closely inside to find out which pins on the base correspond to the acceleration and deflection electrodes, in particular if there is no part number to be seen on the tube. The tube we had for experimental purposes was a 7 cm model of unknown provenance.... [read more]

High Voltage Stun Gun

Can be used agains ferocious animals or attackers, BUT REMEMBER, this device may be illegal in your state.... [read more]

Save Your Ears - A Noise Meter Circuit

‘Hello… HELLO! Are you deaf? Do you have disco ears?’ If people ask you this and you’re still well below 80 , you may be suffering from hearing loss, which can come from (prolonged) listening to very loud music. You won’t notice how bad it is until it’s too late, and after that you won’t be able to hear your favorite music the way it really is – so an expensive sound system is no longer a sound investment. To avoid all this, use the i-trixx sound meter to save your ears (and your neighbor's ears!).... [read more]

Remove common signal from stereo sound

It many times happens, we want erase or decrease in a musical song, the voice of singer or some other sound that usually is written in same level and in the two channels. If we remove between them two signals of channels, we can take in the output a mono signal without the voice.... [read more]

Bedside Lamp Timer

he purpose of this circuit is that of power a lamp or other apparatus for a given time (30 minutes in this case), and then to turn it off.... [read more]