Author Topic: Gravity Wave (Verified)  (Read 16710 times)

amcmann95

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Re: Gravity Wave (Verified)
« Reply #75 on: August 09, 2018, 06:11:38 PM »
Quick question for everyone-- My voltages all match except for the lm324, which is low-- around .3v. *However*, when I pop it out of the socket, the voltages match perfectly. Problem with the chip Im guessing?

m-Kresol

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Re: Gravity Wave (Verified)
« Reply #76 on: August 10, 2018, 04:01:29 AM »
sounds like could be the chip. If you have another one, just try it out.

Could also be that only with the chip inserted you have a connection to something that is then pulling down the voltage. Which pins are out of spec?

Also, what is the problem with your build? No LFO? No Sound?
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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amcmann95

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Re: Gravity Wave (Verified)
« Reply #77 on: August 10, 2018, 07:22:05 AM »
Thanks for the other suggestions m-kresol. Its pins 10, 12, and 2.

I have no LFO. The only pot that really does anything is the dimension pot. Anything with the lm324 isnt working, including the rate led

m-Kresol

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Re: Gravity Wave (Verified)
« Reply #78 on: August 10, 2018, 10:23:19 AM »
ok, so this means you are loosing your reference voltage VB2. since VB2 is only connected to the IC, it would suggest a defective IC.
I would replace it first and hope for the best.
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

B0ttleneck

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Re: Gravity Wave (Verified)
« Reply #79 on: December 10, 2018, 06:19:40 AM »
Hello,
I have a problem with my gravity wave:
I made a homemade PCB and assembled everything.
I made a first test yesterday without putting the footswitch but the result is not good: I have an osciliation output mixed with the sound of the guitar (distorted). pots seems to works.
audio (i play with the pots):
#Invalid YouTube Link#
https://youtu.be/iPWAUoPTICU
Photos:https://imgur.com/a/fGBKqGY

 :o
Where to start checking?
Has someone already had this problem ?

Thanks for your help

m-Kresol

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Re: Gravity Wave (Verified)
« Reply #80 on: December 10, 2018, 10:55:08 AM »
Hi bottleneck and welcome to the forum.

Please check the guidelines for getting tech help here: http://www.madbeanpedals.com/forum/index.php?topic=902.0

go through the individual points and you will likely find the problem. So basically, visually check your component values and orientation, check your soldering for solder bridges or cold joints. Check DC voltages on all ICs and transistors (reference voltages by Cody at the beginning of the post). If you can't find the problem yourself, post the voltages and pictures of your pcb and we'll try to help

happy hunting
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