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I recently made a Madbean Big Muff Rams Head clone for a friend.

It worked well but then he had issues with the output jacks tip prong not touching flush with the guitar cable jack. The LED would stop glowing and the signal wouldn't pass through.

I sorted that problem out by bending the output jacks tip prong so that it touched flush with the guitar cable jack.
I tried explaining that when he sticks his prong into his big muff it's barely touching the sides.
But that probably didn't help.

Anyways, a similar problem is now occurring. The LED has dropped out (stopped glowing) and there is no signal, and I assume no power, running through the pedal when it's on.
The battery is fresh, so it's not that. It won't work with a wall wart either but it did before it stopped working completely.
The problem seems to be occurring with the other jack now, the input. He tried bending the tip prong to touch flush with the guitar cable jack but it hasn't helped.

I am about to get the pedal back to try diagnosing the problem but I was hoping some more experienced pedal builders might be able to help with some trouble shooting suggestions.

My only other solution so far is to ground the jacks with a wire rather than allowing them to be grounded by the enclosure.[/b]
Am I right in thinking this could fix the problem because the circuit would be incomplete if it's not grounding properly?
Or could it be something less simple that might require me to brush up on my multimeter skills?

PS: Thanks in advance for any suggestions anyboby might have[/b]

A bent tip lug would prevent signal flowing but shouldn't cause the pedal to lose power because the ground connection for the battery is usually made between (cock)ring and (wizard's)sleeve.

You could use a multimeter when you get the pedal back to check continuity between all ground connections, make sure the power isn't getting grounded somewhere and there aren't any bad solder joints. If it was working ok, it's likely to be something very simple.

^^^^ This. When I build a pedal I check everything with a multimeter for shorts. Also check the ratings of the components before populating the board and soldering. The multimeter has become my best friend when building. Just as important as my soldering iron. Also check the input and output jack sockets. Sometimes when tightening them the parts can rotate and small tabs can move and touch your tip to your sleeve. No signal at all will pass when this happens.

Ben79 wrote:A bent tip lug would prevent signal flowing but shouldn't cause the pedal to lose power because the ground connection for the battery is usually made between (cock)ring and (wizard's)sleeve.

You could use a multimeter when you get the pedal back to check continuity between all ground connections, make sure the power isn't getting grounded somewhere and there aren't any bad solder joints. If it was working ok, it's likely to be something very simple.

Thanx Ben. You're right, it was a grounding issue because of a bad solder join where the inputs sleeve is grounded to pcb via the footswitch.
Turns out the pedal WAS working with a wall wart so I figured that the battery wasn't grounding to the pcb properly.
Thanx for your help. Thank god I didn't have to get the multimeter out. I still don't really understand them

KaosCill8r wrote:^^^^ This. When I build a pedal I check everything with a multimeter for shorts. Also check the ratings of the components before populating the board and soldering. The multimeter has become my best friend when building. Just as important as my soldering iron. Also check the input and output jack sockets. Sometimes when tightening them the parts can rotate and small tabs can move and touch your tip to your sleeve. No signal at all will pass when this happens.

Thanks CaosCill8r.
Luckily I sorted the problem out before needing to get my multimeter out because I really am clueless with them. Will definitely have to do some study on them.
The problem ended up being a dodgy solder on the footswitch where the negative of the battery grounds from the stereo input to the pcb via the bottom left footswitch terminal.

Thanx for your help. Especially for the tip off about being careful that the jack terminals don't touch.
My friend mentioned that this happened when he tried fixing them but it instead gave a bad electrical interference noise so I guess that was from the inputs sleeve and ring touching rather than the tip.

Glad you got it fixed.

The continuity setting on a multimeter is really simple....it just lets you know if you've got a good connection between 2 points or not, something that can save you a lot of time when you're trying to diagnose a fault like yours. It's what i use mine for most in building and repair. Apart from that, I use my MM to check old resistors to see how close to spec they are and voltages in the circuit (normally on the pins of transistors). It helps you learn stuff - which I certainly need cos I'm a noob too.

[youtube]http://www.youtube.com/watch?v=AwUhuJZvdfM&feature=youtu.be[/youtube]

...don't know if this is any good but just stumbled across it on ssguitar.