Work in progress june 2020

Here's what I have been up to lately. Check out the video below for some talk and sound samples. :)

This is the first time i've done a video to talk about stuff that i'm working on. I'm very uncomfortable to speak in english and to hear my own voice haha, but i'm working on it.

​Perhaps if I get a bit more confident I'll do some video based tutorials (CMOS, Attiny prgramming ect.) in the future. Let me know if that's something that you would like to see.

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Here's a summary with some additional info.

The Monobius 8-bit Micro System
This was a Attiny84 based project with a card/cartridge-slot that I was working on earlier this year in the winter. It was supposed to have 3-4 cards with programs based on old Parasit Studio designs, such as the Arcadiator, Xor'cist ect. but with a few more bonus features.

However, I decided to scrap the card idea, since it felt like it was too much trouble for a gimmick, so now I'm working on a stand alone version instead that I think will be really good. This one will only be avaliable as a fully assembled pedal, not DIY (Sorry).

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The Databus Drive
The second project that i'm working on right now is called the Databus Drive, and it's a huge guitar synth inspired by old 8-bit computers, especially the Gigatron TTL DIY computer that I have built for myself a while ago. 

The idea is that the Databus Drive will also be built inside a custom wooden enclosure with a clear transparent top cover. It's 100% CMOS based (I enjoy developing these kinds of projects alot more than microcontroller based projects) and features a 16x16 LED matrix oscilloscope that I originally developed as an addon for the Multiwave MEGA (before it became Attiny based).
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PCB render - final version will be white with black silkscreen

It has a phaser and a vibrato that are both kinda complicated features to pull off with CMOS only, hence the big number of chips in this one. I had these features going with a microcontroller, but I thought that it was fun to see if it could be done with CMOS instead. Otherwise it's nothing super special. No filter or envelopes. But I think it will be a very cool effect as a whole. Right now i'm waiting for the prototype PCB's and a ton of LEDs to arrive. Can't wait to build this one. :)

If enough people are interested in this one, then I will do a limited run of PCB's for DIY (it's a huge and expensive board). Just note that the PCB isn't designed for any standard enclosure size (but there are some plastic electronic boxes with transparent covers that can suit the PCB).

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A few custom builds
I usually don't accept custom requests, but because of the Corona Situation i've been building a few pedals for birthday gifts ect.

A custom Green Currant Tremolo, built for a member of the band Vidro.
​Check them out if you like raw hardcore punk. :)

The "Darby Fuzz" - A germanium Fuzzface variant with russian NOS germanium transistors and a discrete voltage inverter.

I built the board a long time ago and decided to finally box it up. It was built/designed specifically for this article: https://www.parasitstudio.se/building-blog/manhattan-style-pedalbuilding

If you are interested in the transistor based voltage inverter, you might want to draw up a schematic from the manhattan style layout (I don't have the schematic any longer), and check out Dave Jones video on the theory behind the Cockcroft-Walton Multiplier (same principle can be used to generate negative voltages aswell).
https://youtu.be/ep3D_LC2UzU

A custom modded EA tremolo

​Not much to say about this one. I built it on singlesided copperboard "manhattan style" aswell. It's just such an enjoyable way of building simpler circuits like this one, and the big ground plane makes it good for low noise (one of the reasons the manhattan style is popular with ham radio DIY electronics).

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PCBWay PCB Assembly Service
When I was designing the Monobius pedal I was contacted by PCBWay that wanted me to try their PCB service for free (they even paid for the shipping) if I shared my opinion on their service. I wasn't interested at first, but I decided to try their PCB assembly service since I've never used an assembly service before and it could be a great time saver.

So this post is sponsored by PCBWay since I own them a mention. They guided me through the whole process of ordering and they were very easy to communicate with and the board turned out great, so i'm happy to recommend them and use their service in the future. :)​

One of the Monobius cards being designed (in Diptrace)

PCBWay made the 10x Monobius cards for me with preassembled chips. Now, as it turns out, these cards will not be used, but it nice to learn how the PCB assembly ordering process in case I want to use it for a bigger project in the future.

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That's all for now. For more frequent updates, please check out Parasit Studio on Instagram and Facebook.

Stay safe and keep up the DIY spirit. :)
/ Fredrik