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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Noiseplug – rca plug that plays chiptunes

Do you remember those first 8 bit computers and video game consoles? Do you remember how beautiful music they were able to play? This unusual device is a combination of modern technology and charm of 90’s. A seemingly simple plug, hiding a very small attiny10 microcontroller and two watch batteries inside – plays 2 minutes long Chiptune track, after plugged into the amplifier input.

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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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Interactive mug coaster

Interactive mug coaster, thanks to analog temperature sensor LM35 and uC builded-in analog-digital converter, device can read temperature from standing on it glass. Device calculates temperature and smoothly light-up our drink with slowly changed RGB colours. When temperature is under 20*C then displayed colors are cold, and when temperature is above 28*C then colors are hot. When nothing stands on device (temperatures from 20*C to 28*C) then it automatically swich off. Fusebits are: 4,8Hz internal clock, not divided by 8. Supply voltage is stabilized by 1117 type stabilizer to 3.6V. The red LED requires lower voltage, and current on that…

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Miniature LCD driver – LCD2USB + frontpanel

Miniature version of LCD2USB device, a lcd driver connected to usb port. Because the original pcb was too complicated for home-make, i have projected new pcb – all parts is surface-mounted, pcb width is width of 16 pin connector which is fit exactly behind lcd. I used mini-usb connector, ATMega8 in TQFP package, and some of other SMT parts. As pcb is modified, it need modified firmware available for download below. Rest of description is available on original autor site.

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