frequencycentral Ugly Face Layout - no offboard wiring!

[frequencycentral]

Designed to fit 'landscape' in a 1590B. The plan is to eventually add a second PCB with the LFO - both boards should fit 'portrait' (though I haven't checked) in a 1590BB, ie two rows of controls.

Unverified. Please check for errors before attempting. A messy layout really - 5 jumpers - that's the trade-off for onboard pots.

Ugly face schematic: http://www.experimentalistsanonymous.com/diy/Schematics/Fuzz%20and%20Fuzzy%20Noisemakers/Uglyface.gif
Mick Bailey's mods: http://www.avwz35.dsl.pipex.com/uglyface%20lfo%20&%20mods.jpg
soggybag's mix mod: http://www.super-freq.com/wp-content/uploads/2007/07/uglyface_mix.gif

[frequencycentral]

Just caught an error. 7555 pin 7 should be connected to the output cap. I'll fix it tomorrow.

[Tony Forestiere]

I am sure the jumper under  the Sensitivity Pot can be sussed.
Do you ever sleep? 

[egasimus]

Great! I've been wanting to try this one.

You've been doing a lot of great layouts lately. Why don't you post them in 'Schematics & Layouts', though?

Hmm, have you considered swapping the threshold and frequency pots? I might be wrong, but on a first look it seems that this will be an optimization...

[frequencycentral]

Just caught an error. 7555 pin 7 should be connected to the output cap. I'll fix it tomorrow.

Now corrected.

[frequencycentral]

...and verified.

...and ugly sounding. 

[frequencycentral]

Hmmm, I found the oscillator wasn't low enough for me, so I've added another 0.1uF in parallel with C4, making a value of 0.2uF - nice and low now, but still supersonic at the other end of the pot.

I'm also experimenting with a low value cap to ground on the input to tame some of the glitchyness.

[frequencycentral]

Here's the second, Utility board layout. It contains:

• LFO with Shape control, I've used a pot, but it could equally be a toggle switch. To be wired to the main board with a DPDT to the orange pads
• Tone control. I found a BM type control configured for flat mids and bass/treble boost at either end worked better than the usual scooped mids BM tone control
• Mix pot. To be connected to the main board 'grey areas'  :)l

I'm thinking the audio path would be Mix pot >>> Tone pot >>> Volume pot, so the mix pot is wired into the tonestack.

Unverified. Please check for errors before attempting.