Project Log

FATMAN SYNTHESIZER

Project review

Looking back, around 2003 I had a big interest in music. I owned two guitars, synthesizers and had all kinds of related and assorted equipment. While spending my time delving into the technology itself rather than actual music creation I reached a point where I thought about building instruments myself as I was researching everything from guitars to synthesizers. I still have plans to some day build a left handed version (because I’m left handed) of a Gibson Thunderbird. The Thunderbird bass in particular have to be the most beautiful musical instrument I know of.

Through a friend of mine I found out about a guy who was building his own synthesizers, and while I knew next to nothing about electronics I was heavily intrigued. I got in touch with him and found out he had been at it for a while and to get started he forwarded me to a Canadian company called Paia that made electronic hobby kits, among them a very good entry level analogue synthesizer called Fatman featuring basic wave modulation, Midi interface, and a pretty little case for the circuit board, dials and buttons that effectively sealed the deal for me. It was definitely an ambitious project with regard to my non-existent knowledge about electronics and very basic soldering skills acquired in school a number of years earlier. My enthusiasm was way beyond all that though and I ordered a kit without even blinking, trusting that my passion for the project would bring me home. Which it also did… eventually.

Two weeks later I got the kit in the mail. It was basically just a circuit board, a plastic bag full of components, a metal case and a set of instructions. After a thorough inspection of the kit as well as my tools for the job I got to work, going very slow and taking great care to get all soldering points nice and clean on the board. A few busy nights and a weekend later I had everything in place. The kit did not include a power adapter and I had to buy one compatible with Swedish power outlets giving me about twelve steady volts to drive the whole thing. As I still knew very little about electronics I checked and rechecked everything before the moment of truth. As I hooked everything up and flipped the switch some lights turned on and I heard… nothing.

This is where the initial challenge started to mount and for a long time I was working on solving the problems, spending much time to find and isolate them to begin with. I bought and read up on a multi-tester and started deciphering the circuit board diagrams provided. Tracing signals and voltages along their paths begun to reveal my construction flaws. As I had never done anything like this before I was still quite successful. While testing I found a few “cold” soldering points where no voltage at all got through and that was easily fixed. I also had to replace one of the small IC circuits as I managed to short and destroy it as I accidentally bridged two of the pins with my measuring tool. As It happened I noticed a diode shining at twice the normal strength before going out completely. I got a slight heart attack but quickly tracked down a replacement in an electronics store. As I replaced the old IC circuit everything worked as before.

After the first rounds of inspection I got a weak but steady tone going through the output that could also be tweaked using the knobs. I made the conclusion that the actual synthesizer part was working and now I just had the biggest problem left to solve, the Midi interface. No matter what keys I pressed on my keyboard the sound wouldn’t change. I managed to trace the appropriate signals up and into the Midi processor, and trying to figure that one out turned out to be too much for me at the time. I made a few further attempts over time to solve the problems but failed which lead to a longer break in the project.

As I found enough motivation to have another go at it I got in touch with the support at Paia (the owner and only employee of the company). This guy was super nice and had provided me with great help and more detailed information during previous troubleshooting sessions. It all ended up with him sending me a replacement processor for the Midi interface. I pried out and replaced the old one and when I flipped the switch, begun pressing buttons and turning knobs everything worked like magic! Three years after starting out I was apparently at the goal. It was a great relief and feeling to make the final assembling of the case and wrapping the whole project up. At that time I was barely into music anymore but the investment was worth it many times over. I was really impressed by myself for finally pulling this whole project off despite the problems I had. Most importantly though, not only did I have a lot of fun but I also learned a ton of stuff which might be the most important thing of all.

The images below show the finished Fatman synthesizer.