DIY UV EXPOSURE BOX - MAKE PCB'S @ HOME

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ultraviolet exposure device i built few months ago. it is controled by an arduino pro mini and has a 7 segment display to show the set and remaining exposure time. it uses ultraviolet leds(49 total)bought cheap from ebay.
you can wire the arduino and the rest components using the diagram below.this way i made it too.you can connect any common cathode 7 segment display as long as you know witch pin is the segment shown in the diagram.or you can find it by applying about 3volts to each pin to see witch segment lits and write it down.(as i did)or downloading its diagram if exists..
then programm the arduino with the code given in the link below.you can skip the circuit with the mosfet and the optocoupler and connect a 5 volt relay as shown in the diagram(relay output & ground) to controll the leds.
if you liked this project please subscribe to my channel for more future projects....





arduino code : https://drive.google.com/open?id=1SK-jNM7jZIcx-jIN8e3rleN_-12L9IQG

Comments

  1. praji1818 August 2020 at 20:47

    Hi, i tried your code and built the circuit, everything works fine, but the display brightness is very low.. is there a way i can increase the brightness for the 7 segment LED display in the code?? i am using a common anode, green 0.56 inch display 4 digit

    ReplyDelete

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