# The Abyss - Blown Yellow LEDs



## Many__Of__Horror (Aug 8, 2019)

I have just finished building The Abyss, had it on looper adjusting the knobs to see what it does and I have blown my second Yellow LED tonight. (Lucky I have it socketed)

Any help on what could be causing this and things I could try to resolve?


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## bergera (Aug 8, 2019)

I've been running mine for a couple practices now and am still working.  Do you have the intensity cranked? I'm wondering if you have a resistor wrong leading to that led that is causing it to get more voltage and burn out?


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## bergera (Aug 8, 2019)

Looking at the schematic r23 is 4.7k and r25 is 47k and r24 is 100k and r26 is 100ohm. I could see myself swapping or getting some of those messed up, so maybe start checking there?


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## zgrav (Aug 8, 2019)

Are you using 9 volts for the incoming power?  The suggestions above sound like the right place to start.  I would also check R22 if the other resistors are the right values.


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## Many__Of__Horror (Aug 8, 2019)

Thanks for the suggestions makes sense now looking at the schematic. All a learning experience. I am using 9 volts yes.
Checked a few quickly this morning over breakfast and R25 is not reading correctly coming in at 33.69K, not able to get a stable reading from R24 either. R22, R23 & R26 are reading correctly.
I'll look to desolder the dualpot to get access to those resistors tonight when I have time.
Will update with outcome


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## music6000 (Aug 8, 2019)

This may help you, just Click on BANDS for 5 bands.  Just match your bands: 
http://resistor.cherryjourney.pt/


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## Many__Of__Horror (Aug 9, 2019)

Thanks for that link, it's great. Colour bands match the BOM values. Wonder why R25 was reading so differently.


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## zgrav (Aug 9, 2019)

resistor are difficult to read when they are in circuit due to interactions with other parts on the PCB.  were both of the yellow LEDs that failed turned up to be very bright using the trimmers?


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## Many__Of__Horror (Aug 11, 2019)

I was definitely testing out the pedal to see it's highs and lows, but not sure exactly when they blew. Had a rare 20mins freeto do some testing tonight and couldn't make another blow. Will keep putting it through tests to see if stable now or find the culprit if not. Thanks again


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