I’ve decided that my final circuit for this element will be a distortion box placed inside one the emoji cuddly toy that I bought a few weeks ago (at the bottom of my breadboard synth blog!). I was originally going to build a touch sensitive synthesiser in there, where the more someone squeezes the toy, the more distorted/horrifying sound it makes – however I realised the circuit I make will probably be very delicate, so I don’t know if it will react well to being squeezed a lot.

For the distortion circuit I have decided to follow the Junkyard Jam Box book again, this time building the ‘Mud ‘n Sizzle’ fuzz preamp. Before I started soldering it together I was still feeling a little intimidated by the whole process as the previous synth I made did not go so well for me. However, this time I have the correct PCB and all the right parts to make it work!

To start off, I soldered one wire to each of the potentiometers I’m using for the circuit – one controls volume, and the other tone. I also soldered an electrolytic capacitor to the tone knob:

I then soldered the power switch to the battery clip and a resistor, which in turn was soldered to an LED:

I then started soldering the wires to the input and output jacks, and attached to the volume knob to the output jack:

It was now time to start soldering components to the PCB, I started with the transistor, two resistors and a capacitor:

The way of making connections on this PCB, which has no predefined traces, is to arrange the components you want to connect in a line and then solder the connections together. It looked like this:

I subsequently snipped the ends of the wires. Then I started to solder the potentiometers and jacks onto the board, along with another couple of resistors:

The final thing to do was to create a ground connection through the circuit. I did this by connecting the negative lead of the battery clip to the board, in between the bottom connections of the two resistors that run parallel to each other in the picture above. After that I got some uninsulated wire and ran connections from the potentiometers, jacks and the LED to the the same row as the negative battery wire. I employed the same connecting technique I had used before by soldering all of the connections together. It looked like this:

Something I found really difficult was that the uninsulated wire kept disconnecting from the jacks after I had soldered it on. I don’t know why it kept doing that – maybe it could’ve been to do with the fact I’m relatively inexperienced with soldering my technique isn’t great. My technique to get around this was to wrap the end of the cable around the connections as much as possible and then solder it together. It didn’t seem like a 100% correct thing to do, but it works for now.

It was now time to test out the circuit! Initially I wasn’t getting any light on the LED, which meant the signal was going wrong somewhere. After checking the PCB I noticed one of the ground wires had come disconnected – I re-soldered it and also moved some wires which I noticed were touching parts of the circuit they weren’t supposed to be connected to. One of these must have fixed the issue because the light turned on after that.

I took the circuit downstairs to test it out on my valve amplifier with my guitar. At first, it was picking up radio signals and not much else. I was a bit concerned but I plugged my guitar in anyway. The radio noises stopped soon after (I’m not sure why), and I got a really nice crunchy-fuzzy overdrive sound! What a result! This is my first circuit I’ve soldered together that actually works. Now I need to put it in the emoji toy…

I’ve attached an unlisted YouTube link of me playing my guitar through the circuit as myblog won’t let me upload longer videos:

https://youtube.com/shorts/e-W2Q7CRYVI

I am really pleased with the outcome of this as part of me was expecting the circuit not to work at all. I think I’ve gained a lot in confidence from finishing the circuit off, and now I feel ready to take on more challenging circuits in the future. One thing I’m concerned about is the radio noises – they started and then stopped without me doing much so I’m worried there might be something temperamental about the circuit still. I’m also concerned about the fact that when the circuit is in bypass mode the signal coming through is still a little fuzzy, even though I’m playing through the clean channel of my amp. Still, the circuit makes a great distortion sound so for now I am happy.