Electronic – I am building the own distortion pedal but every time I connect it to a 9V power source it does not seem to work

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I am trying to build my own distortion pedal. I initially built this on a breadboard and connected it to a 9V power supply and it seemed to work fine when I connected it to my electric guitar. So I decided to solder it to a prototype PCB board. The ground and live wires are connected to a 2.1mm barrel jack and is then plugged into a 9V power wall adapter. But for some reason every time I try to power up the circuit board the live and ground wires between the 2.1mm barrel jack and the circuit begins to smoke and the plastic casing melts. I am unsure of how to fix this problem and I was wondering if anyone had any solutions? I've added the image of the circuit and schematic belowThis is the circuitthis is the underside of the prototype boardthis is the circuit for the pedalHere is the schematic for the pedal

Best Answer

For a start it appears that you have forgotten to cut the traces between the pins of the chip. That means that pins 1 and 8 are connected, 2 and 7, 3 and 6, 4 and 5. They shouldn't be.

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Figure 1. A Vero tool is rotated by hand to remove copper around any hole thereby isolating the strips either side of that hole. This tool doesn't go right through the board as in Figure 1.

If you haven't got one of those then a 3 mm drill bit twisted in your fingers will do the job.

Next you shouldn't really be connecting all the wires directly on the bottom of the board. Keep components and wires on the top side and at the edges. That way you'll be able to inspect it more easily.

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Figure 2. Rather neat circuits can be built on Veroboard if the components can be mounted perpendicularly to the direction of the copper tracks. Here there are no flying wires and all cross-connections are done with components or wire links. Image: Wikimedia Commons.

Note that the links are all straight wires going across the direction of the strips. To get from one side of the chip to the other would take two links.

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