Paul's Stuff

Ghidirah - Podular Synthesizer^*

I chose the name Ghidirah because I thought it sounded neat.  It wan't until later that I made the connection of 3 heads = 3 VCOs.  Granted Mothra also has 3 VCOs, but so what. Ghidirah is still very much a work in progress.  So far, I have the panel, mounting board, and a couple of modules completed. Updates 9/20/2003 - Second VCO added. Only the third VCO and EG are left to go.

Modules 3 VCOs 12dB State Variable VCF 24dB Low Pass VCF Dual VCA (Linear/Exponential) 3 ADSR EGs 2 LFOs 5 Channel Mixer 3 Channel Mixer

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Overview

Ghidirah started when I came across a blank 7U panel and as an academic exercise, decided to see how many modules I could cram into it.  The next thing I knew, my drill was starting to overheat from all of the holes.  I was suprised to fit as much into it as I did.  The extra VCO and ADSR will come in handy.  While Ghidirah is not actually a 'real' modular, I believe that it can be considered one in spirit.  Unlike Mothra there are no normalized connections between modules. 

Almost all of the modules are based on the excellent ones desinged by Ray Wilson.  For the most part, the only changes made to his original circuits were minor; adding addition CVs, component spacing, etc.  The pages for each module will eventually have the modified PCB patterns.

This is the first time that I have tried to make a polished, legended panel, and though it is far from perfect, I am pleased with the results.  Mothra is labeled with dymo tape. If anything this is an improvement.  Here are the steps I used:

1. The surface of the panel were sanded and painted with gray automotive lacquer.  After it dried, it was given a couple of coats of clear gloss enamel.  The gloss provides a nice smooth surface for the decals to adhear to.
2. The legend for each module is printed onto model decal paper.  This paper is relatively cheap and is available at most hobby shops.
3. Each sheet was coated with about 2 coats of clear gloss enamel.  Without this clear coat, the decals will fall apart on contact with water.
4. After the decals were dried, they were cut to shape and affixed to the panel.  Decal setting solution and solvent were used to get the decals to snuggle down onto the panel with a minimum of air bubbles and silvering.  This step was the most difficult and time consuming since you need to wait for one decal to set before continuing on to the next.
5. After the decals were completely dry (about 2 days), I used an exacto to remove the decal film from the drill holes, and gave it a few more blasts of clear enamel to seal them.
6. The clear gloss takes a few days to cure completely. I used this time work on the panel's back plane.  When it finally cured, I gave the panel 2 coats of sprayed satin urethane.  The urethane is a bit more durable than enamel and the satin cuts down on reflected glare without making it look too flat.

I used individual decals for each module since finding decal paper that is 19"x12.25" and a printer that can handle it is a bit hard.  Custom decals can stretch a bit so care was needed to ensure that they would line up correctly (or in my case, almost line up correctly).

Podular - A made up word.  Panelized Modular