Author Topic: Function f(x) DuoVibe  (Read 1446 times)

m-Kresol

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Function f(x) DuoVibe
« on: June 26, 2014, 03:16:51 PM »
Finally! I managed to finish CJ's DuoVibe after all those month. Actually, I built it in January, but it didn't work and was sitting around waiting to be picked up and debugged for quite a while. I have no clue why it didn't work in the first place since it worked prior to boxing and all the connections checked out. After fiddeling around, I found that loosening the pot screw just a little made the interior LED flash again. So I moved it up from the pcb just a little to align it a little better and it worked. After that, I was waiting for proper knobs for a few weeks. Long story short: they arrived today and it looks sweet! Cover is random as the last one :D
I think the LDRs/LED I used where not optimal, since the LED is nearly invisble before 12 o' clock and the effect is rather subtle even when cranked up. I still like it, though I think I won't use it to often.

          
I build pedals to hide my lousy playing.

My projects are labeled Quantum Effects. My shared OSH park projects: https://oshpark.com/profiles/m-Kresol
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culturejam

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Re: Function f(x) DuoVibe
« Reply #1 on: June 26, 2014, 03:41:22 PM »
I would try a yellow or red LED.

Also, I'm not sure of the specs on those metal LDRs. They sure are cool, though. The ones from Tayda work very well in this circuit.

midwayfair

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Re: Function f(x) DuoVibe
« Reply #2 on: June 26, 2014, 04:10:42 PM »
I would try a yellow or red LED.

Also, I'm not sure of the specs on those metal LDRs. They sure are cool, though. The ones from Tayda work very well in this circuit.

They're about 5K-10M. (Silonex 7532.) And this is one case where the ones from Tayda probably are better, since it's the light resistance that matters most (not dark resistance like in a lot of circuits), and they have a 1K light resistance.

Try backing them off the LED a little before changing the LED.

Your green block is going to crash! You should rotate it.
Myself's music & things I make: http://jonpattonmusic.com. My band: http://midwayfair.org. PCBs of my designs from: http://www.1776Effects.com (Bearhug Comp & Cardinal Harmonic Trem); http://www.jmkpcbs.com (Hamlet+ delay & Blue Warbler envelope vibe); Snow Day OD/Flabulanche: www.madbeanpedals.com

m-Kresol

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Re: Function f(x) DuoVibe
« Reply #3 on: June 26, 2014, 04:25:49 PM »
I would try a yellow or red LED.

Also, I'm not sure of the specs on those metal LDRs. They sure are cool, though. The ones from Tayda work very well in this circuit.

They're about 5K-10M. (Silonex 7532.) And this is one case where the ones from Tayda probably are better, since it's the light resistance that matters most (not dark resistance like in a lot of circuits), and they have a 1K light resistance.

Try backing them off the LED a little before changing the LED.

Your green block is going to crash! You should rotate it.

I socketed the LED exactly for that matter, but it was to high with the sockets. Desoldering was a PITA and I'm afraid of changing it again to be honest. I don't recall what LDRs those are. I ordered them via RS components and just tried to get as close to the referred specs from the build doc - this was before I started ordering from Tayda as well.
I build pedals to hide my lousy playing.

My projects are labeled Quantum Effects. My shared OSH park projects: https://oshpark.com/profiles/m-Kresol
My build docs
My etching tutorial

pickdropper

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Re: Function f(x) DuoVibe
« Reply #4 on: June 26, 2014, 04:51:19 PM »
Niiiiiice.  Dig the Tetris.
Function f(x)
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m-Kresol

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Re: Function f(x) DuoVibe
« Reply #5 on: July 19, 2014, 03:24:56 PM »
Update:
I finally switched out the green LED for a yellow one after dry testing red vs. yellow. I also swapped the LDRs for some tayda ones although after swapping I liked the silonex a little better. I didn't socket because it was a pain in the ass to desolder and solder under the pots...
I tested the LDRs after desoldering. the silonex I had in there are about 125R light/250k dark so the effect was a little stronger than with the tayda ones which tested at roughly 1k light, 5k dark. These values are way off from what the build doc states but they work fine. Somehow, I still think that LDR specs are never to be trusted ;) I think the silonex I ordered should have been around 2M dark...
Anyhow, the effect is working now and is less subtle. And I also got rid off a weird bug I had... Tightening the depth pot washer somehow made the LED go dark or only respond on the upper end of the depth control. Reheating the solder joints, some insulating tape and a little looser washer fixed that for me.
I build pedals to hide my lousy playing.

My projects are labeled Quantum Effects. My shared OSH park projects: https://oshpark.com/profiles/m-Kresol
My build docs
My etching tutorial