Ugly face works partially

[jmusser]

I put the Ugly Face together of the past couple evenings. So far, the only part of it that works is the oscillator section, and I can get it to work while the stomp switch is in bypass too, only not nearly as loud. I'll have to go through it tonight at lunch, since I'm at work, and see what I've botched. I used a Radio Shack LDR coupled with a large red LED. The LDR measured 9.8 meg after I wrapped it in heat shrink. I believe that's what I read in someone's build article that they used, and there's was around 10 meg like this one. I used the TLC555 timer and an LM386 in the circuit. The oscillator portion is LOUD! I've been wanting to build this one for awhile, so hopefully, I'll get it whipped into shape. I'd guess a miswire has snuck in there somewhere.

[petemoore]

the osci is loud, and bleeds through on mine when in bypass mode.
 debugging mine, I recently re built one, was a matter of applying th dmm to find resistances, in cct., continuity, etc. visual inspections etc. someone may have a better way, this is how i got mine working...i have no idea what voltages to look for except the obvious Gnd and  V+, and no really wierd like readings like an input reading near gnd voltage.

[Tim Escobedo]

The output of the oscillator has a volume control to cut the effect level to where ever you want it.

It is quite possible for the oscillator to bleed through when bypassed. However this generally only happens if the Threshold is set so that it free oscillates regardless if there's a input trigger signal or not.

[NaBo]

I put mine together tonight

I used a 5 mm normal green LED in mine, and i have no clue how high the resistance goes on my LDR, cuz my cheapo DMM only goes to 2 megohms... sounds excellent though.

Its so sweet that it makes me want to cry.  i've been making laser-cannon noises, and many others, all night!!!!!  well, mostly laser-cannon noises.  huge fan of the laser-cannon noises.  :wink:

hey... umm...  what tapers should all the pots be?  are they all log or is frequency linear or what? :oops:

[jmusser]

That's a good question. I used all linear except for the the volume. That don't mean it's correct, but that's how I had it figured. I'll get a chance to look at this thing tonight and go through a clean schematic with a highlighter. I labeled every component, so I'm sure I'll find the boo boo. I figure I've wired out to one of the pots wrong. This circuit really doesn't have a lot of components, but it makes up for it in off board wiring! I put the LED and LDR together with some masking tape to hold them together, and then I enclosed them together with heat shrink. I put super glue on the ends where the leads came out, and held them together with a couple of small vice grips until they sealed. I don't figure the optoisolator is the problem. I figure it's something simple. I was going to go through it yesterday after it's trial, but I like to get a couple hour nap before I do a 12 hour night shift. I know that's kind of selfish.

[jmusser]

Well, it took me about 15 minutes to find the error of my ways. I left off the jumper that goes from the 2.2uf output cap of the 386 (pin 5), to the reset of the 555 timer (pin 4). I'd say once I connect that one up, we ought to make a variety of very ugly sounds. That'll be tomorrow though. I still have 9 hours of a 12 hour shift to get through. I'm glad to find it.

[Joe Viau]

If I may add onto this post, how would I build an Uglyface without the photocoupler? What changes would be necessary?

Thanks,
Joe

[jmusser]

That would be a question for Mr. Escobedo. The way I understand this optoisolater, is that the LED is allowing so much light into the photcell to vary it's resistance. I'm guessing that it's based on how you play that varies the amount of light that the LED emits to the photocell. The more light, the less resistance. I believe that this feature is the heart and soul of this effect, and makes it sound like it does. If you used something else (whatever that would be?), it would be a different animal. I may be totally wrong, but this is how I believe this part works. I belie John Hollises "Rock Face" has the same feature.

[Joe Viau]

I was going to build this effect for my 13-year-old son.  But upon re-thinking this, why would I take out all that fun?  

[Tim Escobedo]

You can certainly build it without the optoisolator. Simply omit the optoisolator, P3, and the 2.2uF cap connected to P3 above. That's it.