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DIY Stompboxes => Building your own stompbox => Topic started by: jimbob on January 17, 2004, 03:30:10 AM

Title: Finally got it after " forever" Forgot a 10k resis
Post by: jimbob on January 17, 2004, 03:30:10 AM
:(
I had this problem a while back and thought if i started all over the problm would correct itself...hmmm nope.. Anyway, Ts sounds great for about a minute than it starts to fizzle out sounding like a fuzz as it grows quieter until nothing. If you touch just about any place on the bottom it begins to work again and the problem repeats itself. I looked all over for a short and replaced a few parts that may have looked suspicious and still have the problem..I bet its something simple im completely overlooking. Has anyone had this problem w an effect or have any idea what the problem may be? I really like the sound and wanna play with it.
Title: Finally got it after " forever" Forgot a 10k resis
Post by: Nasse on January 17, 2004, 04:12:35 AM
:oops: I had same problem 20 years ago with my self-made drum box. Snare drum "noise" sound made a strike after few minutes from power on. When I placed my finger on some components somewhere in the circuit board, it worked sometimes. Not very practical when you tried to play guitar same time. I replaced my finger with wet piece of paper and it worked few days. Later the snare drum noise was dead all the time. I changed transistors and some caps around what made the noise sound but never got it working any more. It will be mystery forever, I believe. :oops:

But I have thought it might have been a bad electrolytic cap, a faulty transistor or a very nasty bad solder joint.
Title: Finally got it after " forever" Forgot a 10k resis
Post by: jimbob on January 17, 2004, 05:49:38 PM
Finally got it after "forever!" Turns out it was a 10k resistor i completely forgot to put in since the area was already crowded. Its the one next to  the 4.7k and the 4558 ic. Wow! I so wanted to give up so many times and just gave it time. Another day, i would tell myself! I know it no biggie but im excited. I had completely took it apart piece by piece as well as solder- cleaned the board- chked every component-and somehow i still managed to miss it.
Title: Finally got it after " forever" Forgot a 10k resis
Post by: Paul Perry (Frostwave) on January 17, 2004, 05:56:29 PM
I think we have all been there.... it isn't a bad idea when all else fails to do a 'headcount', just total up the components yu can see with the ones on the circuit diagram!
Title: Finally got it after " forever" Forgot a 10k resis
Post by: jimbob on January 17, 2004, 06:13:01 PM
Im still not sure how it managed to work even for a few minutes before it stopped..My only guess is that the 10k kepps the ic from overheating and since it wasnt there it over heated after about a minute and shut down. I did notice it sounds better w the gain channel on my tube amp than with the clean channel.
Title: Finally got it after " forever" Forgot a 10k resis
Post by: dan on January 17, 2004, 10:34:48 PM
i'm still debugging my project. and to think, it worked really good for a couple of minutes and then it died. it's like a mystery.....
Title: Finally got it after " forever" Forgot a 10k resis
Post by: jimbob on January 17, 2004, 11:45:19 PM
What are u working on?
Title: Finally got it after " forever" Forgot a 10k resis
Post by: Brian Marshall on January 18, 2004, 05:55:20 AM
Quote from: dani'm still debugging my project. and to think, it worked really good for a couple of minutes and then it died. it's like a mystery.....

might check for reversed electyolytics.... that happened to me once with some rack gear i was fixing   Luckilly it was easy to spot, because the cap leaked.
Title: Finally got it after " forever" Forgot a 10k resis
Post by: ExpAnonColin on January 18, 2004, 12:09:27 PM
Quote from: Paul Perry (Frostwave)I think we have all been there.... it isn't a bad idea when all else fails to do a 'headcount', just total up the components yu can see with the ones on the circuit diagram!

Always a good plan of action-and man, I feel your pain :)

-Colin
Title: Finally got it after " forever" Forgot a 10k resis
Post by: aron on January 19, 2004, 02:24:13 AM
Quote from: jimbobFinally got it after "forever!" Turns out it was a 10k resistor i completely forgot to put in since the area was already crowded. Its the one next to  the 4.7k and the 4558 ic. Wow! I so wanted to give up so many times and just gave it time. Another day, i would tell myself! I know it no biggie but im excited. I had completely took it apart piece by piece as well as solder- cleaned the board- chked every component-and somehow i still managed to miss it.

Is that the bias resistor???
Title: Finally got it after " forever" Forgot a 10k resis
Post by: jimbob on January 19, 2004, 02:28:44 AM
NOt sure what it it. Im still really new to all this. On the ggg layout its the 10k between  the ic and the 4k7 that stands on its end.  http://www.generalguitargadgets.com/v2/diagrams/ts_lo_808.gif
what i cant figure out is how it even managed to work for even a few minutes without this.