Semi-automatic spot welder 2,6V 1kA


This welder, thanks to the limit switch, after lowering the upper electrode arm, automatically enables the welding process in a safe and proper way. First, it waits 1 second so that the user have time to clamp electrodes on welded material, and then turns on the weld current for time in the range of 0 – 4 seconds, which is set by the potentiometer. This allows both hands to be free, and there’s no need to use the foot switch.

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4x100W car audio amplifier


400W car power amplifier. Based on a push-pull converter with TL494 (KA7500) driver, 500W of power is enough for four TDA7294 integrated amplifiers. Three three-digit multimeters on front-panel shows actual battery voltage, temperature, and estimated output power.

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Kolorofon na USB


This project is a remake of an old discolights pod. Original 24V 5W bulbs are changed to 230V 40W with E14 thread. Original driver board has non-typical signal input. This driver is based on the FT245RL chip, a USB-LPT converter – so you can use it with PC applications such as discolitez. Low voltage part is supplied directly from the USB so there is no need to to use any transformer…

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Nie-zwykła żarówka – RGB


The “not-ordinary bulb”, as title say, typical glass and metal bulb with electronic inside. Powered from miniature AC-DC converter – i have used that one from 230-5V USB chargers – it has enough power (about 500mA) for few RGB leds. Next is Attiny13 (SOIC8 package) based RGB driver, it not only can change colors, but has 3 modes and an automatic color and mode saving to eeprom memory – so after power up you always will see last seen mode and color.

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