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Moodring Help!

Started by Alaboogie, August 26, 2014, 07:23:34 AM

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Alaboogie

Just got it in the mail today and was WAAAY too excited to build it. Was missing a few capacitors/resistors so I decided to sub some parts here and there (ex. instead of a 20k resistor, just put a 22k resistor in, and instead of a film capacitor, just used a ceramic one, among others...). Also was short a 1n5817, so i subbed a 1n34 in. Fired her up and all i heard was some pretty loud static with the dry signal in the background. There was either no static at all, or the smallest turn of the ring knob would make it loud. Almost oscillation-ish...So i checked the voltages and compared them to the ones at the end of the build doc, and for the most part all the voltages were off.

Decided that D1 (1n34) was the culprit so I switched it out for a 1n914 and it brought the input voltage back up, but it was still short about .5 a volt (~8.7V). The first pins of all the IC were closer to the voltages at the end of the build doc but like i thought it was going to be, they were all short maybe .4-.5 volts compared to what they should be. I should mention all the rest of the pins were all off considerably.

I ran her through my amp and signal passes both when signal is on and off and when playing with the trimmer, if put to the extreme, I got oscillation. But there is no sign of reverb at all regardless of where the knobs are, effect is basically not there and then oscillating.

I'm taking a break until tomorrow, since starting it, populating, and then diagnosing, it's probably been 5-6 hours (need a fresh perspective tomorrow!) but can anyone tell me what could possibly be the culprit? I checked the orientations of all the electros and they're all fine, checked the diode orientations, and save for going through all the values, could there be something i'm overlooking?

Still kind of new to diagnosing (luckily 99% of my pedals fire right up, and the ones that don't are because of simple fixes like pots shorting on the board, not grounded, flipped tip and sleeve cables, etc.), HALP!!! I MUST HAVE TOANZ!

Thomas_H

The 1N5817 was choosen for its low forward voltage. Subbing it will change the voltage readings in your circuit as you just have seen.
Without any pictures it is hard to guess what is up.
You can check the voltage at the +5V pins to see if this part is working.
You also may have accidently an OpAmp in the wrong way. Happens to me from time to time, so you might want to check orientations.
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