Yes, the people who bring you those repair manuals for cars, vans and suchlike, have produced a DIY mini synthesizer kit.
Packaged in a picture-card box (above (which also doubles as the housing for the synthesizer)), the kit contains all the parts and instructions to make your own Stylophone-like synth (without the unnecessary stylus).
The kit contains a pre-assembled circuit board, potentiometer/switch, four micro push-buttons, a blue and green LED, loudspeaker, battery box, a whole metre of wire and a couple of nuts and screws. The unit is powered by three AA batteries.
My soldering techniques are a source of national humour, and not wanting to ruin the kit (a present from my dear partner) I posted it off to the only person I know who can wield an iron in anger and come out the other side having for the job done quickly and efficiently. I’m talking about none other than the fabulous Dr Andrew Armstrong, whose BackOffice Shows are the talk of YouTube (any one of those preceding links will take you to the same place – please take the time and courtesy to check out The Doc’s Channel as there’s something in there for everyone, I promise you. And make sure you subscribe to his Channel too.
Don’t forget to click on any of the images for the BIGGER picture.
The synth kit is based on a processor made by a company called Holtek, a Taiwanese-based semiconductor design centre and provider. The processors themselves aren’t widely used in the hobby community, and as a result, we don’t really know the type of chip used or its part number. The source code of the CPU hasn’t been published either, and the manual of the kit only outlines the basic modes of operation.
When assembled and batteries fitted, the synth is operated with your finger by running it up and down the copper track (the manual helpfully notes that breathing on your fingertip first makes a better contact!)
The effects buttons allow for tremelo and envelope modulation. On the opposite side of the keyboard are buttons allowing for sharp & flat notes. The envelope modulation is enabled by pushing the lower right-hand button next to the green LED. The amplitude of the sound signal is periodically changed, and the green LED begins to flash. The range and speed of the amplitude change can be modified in ten steps by using the same push-button. Each press of the button advances the effect by one step. The flashing sequence of this green LED is changed accordingly. The rapidly flashing LED indicates a rapid change of the amplitude by small amounts. The the eleventh push of this button, the envelope modulation is disabled and the LED becomes constantly lit once more.
The tremelo button is next to the blue LED. It changes the frequency of the note played periodically. The blue LEd flashes this time, and the range of the frequency change can again be modified in ten steps by using this push-button. The tremelo is advanced one step by each push of the button. The slower the LED flash, the larger the frequency change. The eleventh button push, again, stops the LED flashing and switches off the tremelo function.
It’s a nice little kit – well thought-out – and nicely presented in a stiff card box with faux synthesizer sliders and buttons printed on it. If I ever get competent at soldering (don’t hold your breath) I may have a go at making projects for myself. Meantime, I really DO suggest you go look at the BackOffice videos on YouTube.
Sincere thanks again to Andrew for his perseverance!
Here’s a LINK to Andrew’s build video of the Haynes kit. Enjoy!