Got an old power supply from a friend, he got it at the flea market for a couple of euros. Worked great, but the knob just had numbers from 1 to 9, and for a precise measure I always had to connect a multimeter...
So decided to add a mini voltage meter to it.
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Step 1: Gather Your Tools and a Voltage Meter Display.
a multimeter, solder iron and solder, hot glue gun, screw drivers, Dremel (or cheap model, like mine) .
I got the voltage meter in green to match the power supply, but then I realise with low voltages the contrast fade a little.
Step 2: Test Everything
Test with a multimeter, the power supply and the voltage meter and match the voltage from the multimeter to the voltage meter. (there is a small potentiometer on the back to regulate the voltage displayed).
Step 3: Disassemble the Cover and Decide Here You Can Place the Voltage Meter.
Open the lid of the power supply and the check the best place to accommodate the voltage meter.
In my case, there is a kind of a slot to add another component, and the only surface I needed to cut was just 0.8mm of the front aluminium panel.
Place some tape to protect the cover, mark and center the measures for the slot.
Start cutting, make the cut tight and use a file to level the cuts. Test the slot with the v.meter before you glue or lock everything in place.
Step 4: Glue and Connect the Voltage Meter.
I used double side tape, on a larger base, then lock it with hot glue. Just be sure everything is level with front.
Connect the + and - wires to the out of the power supply, I didn't solder the terminal, just used a couple of nuts.
Step 5: Close the Lid and It's Done
hope you find this instructables useful and have fun.