LED Troubleshooting in Speedball

dpitch40 · 5643

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Offline dpitch40

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Reply #15 on: January 10, 2013, 02:00:52 PM
Just got the replacement tubes. Put them in, turned the amp on, gave them time to warm up, and plugged in some headphones; the crackling continues. So i think we can eliminate the tubes as the problem. could this kind of erratic behavior just be a bad solder joint? Or could one of the other components (probably in the Speedball) be bad?



Offline Paul Birkeland

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Reply #16 on: January 10, 2013, 02:01:22 PM
A bad solder joint would indeed cause crackling.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Grainger49

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Reply #17 on: January 10, 2013, 02:48:49 PM
There is "the Chopstick test."  It is listening while you prod tube pins, terminals and any solder joint with a fully insulated prod.  A chopstick is just fine.  So is a wooden pencil if you use the blunt wooden end. 



Offline 2wo

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Reply #18 on: January 10, 2013, 04:56:30 PM
Bamboo Kabob skewers. Thin and have a point. Available at any supermarket...John 

John S.


Offline dpitch40

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Reply #19 on: January 12, 2013, 07:22:00 AM
Update: I used a plastic pen. I was able to induce very loud crackling by poking at the three braided wires with it (which is where I previously had a similar problem a few months ago). I have the chassis flipped over and am trying to get the crackling to happen again on its own so I can make sure they are the same issue, but it hasn't happened yet after running the amp for several hours. I suspect it might be heat-related, and th superior ventilation of having the amp flipped is preventing it.

EDIT: Also, hitting the wooden desk the amp is sitting on causes it to crackle softly in the right ear.
« Last Edit: January 12, 2013, 11:12:44 AM by dpitch40 »