SOLVED Kliche: Strange Issue…

[Coda]

So I just completed a Kliche build, and is doesnt worn (not surprising). This one is different, though. Firstly, I get bypass…but only if the gain control on the pedal is way up. The volume control controls the volume with the pedal off. When I turn the pedal on, I get almost nothing, unless I crank all controls, and keep the gain at zero. With that, I get a quiet tone. What the hell is going on with this one?

 

[zgrav]

also make sure your white wire is connected to the tip on the stereo jack and not to the "ring" contact point.

 

[Coda]

I think that one or both of those white wires will also show that it is connected to ground. check them when you do not have anything plugged into the jacks and see if that is the case. If one of the white wires is connected to ground, check the other side of your PCB to see if you have a short between the ground and tip wires where they are soldered into the board.

if the white wires do not show any connection to ground when no jack is plugged into them, then you need to figure out why that changes when a cable is plugged in. plug in a cable in to one jack and test it to see if the tip then shorts to ground. if it does not, then remove that cable and plug it into the other jack. test the other jack.

if you are getting something shorting to ground when the cable is plugged in but your jacks look OK -- check your cable that you are using to test the pedal to make sure there is no short in the cable between the tip and ground.

The output jack is the problem jack. I removed the jack and the wires from the board, and the pads still read as shorted to ground.

 

[zgrav]

do you have another jack to replace that one? give it a try and let's find out what happens.

 

[Coda]

do you have another jack to replace that one? give it a try and let's find out what happens.

I do, and will. But will it make a difference if the pads are showing short at the board?

 

[zgrav]

Sorry -- I misunderstood your last message. I thought you were referring to the output jack having the short to ground and not something on the PCB. If the short is on the board at the output side you need to find it. Can you post a detailed picture of the other side? If there are no obvious solder bridges on the parts near the output, you can use the schematic to identify the parts where there is likely to be something connecting to ground that shouldn't be.

 

[Coda]

Sorry -- I misunderstood your last message. I thought you were referring to the output jack having the short to ground and not something on the PCB. If the short is on the board at the output side you need to find it. Can you post a detailed picture of the other side? If there are no obvious solder bridges on the parts near the output, you can use the schematic to identify the parts where there is likely to be something connecting to ground that shouldn't be.

 

[Coda]

Could the short have something to do with the footswitch?

 

[JamieJ]

Could the short have something to do with the footswitch?

I would assume not. If you think it’s the output pad itself may consider sending a jumper from R30 to the output jack tip to see if that stops the grounding issue.

 

[zgrav]

check your wires going between the pcb and footswitch to make sure none of them are shorting out against anything. if you test the wire for S2 does it connect to ground? does it still connect to ground after you press the footswitch? if S2 is grounded when the footswitch is in both positions, it means your short is somewhere on the trace that connects to S2. double check the resistor value for R30. Are you showing a connection to ground on each side of R30?

take a real close look at your solder connections to see if you have any that are shorting against one another. some look close together.

 

[JamieJ]

As @zgrav said

What about that joint on the switch - looks suspect. Doesn’t hurt to reflow them with some extra solder.

 

[Coda]

check your wires going between the pcb and footswitch to make sure none of them are shorting out against anything. if you test the wire for S2 does it connect to ground? does it still connect to ground after you press the footswitch? if S2 is grounded when the footswitch is in both positions, it means your short is somewhere on the trace that connects to S2. double check the resistor value for R30. Are you showing a connection to ground on each side of R30?

take a real close look at your solder connections to see if you have any that are shorting against one another. some look close together.

S2 is grounded every other time, so that is normal. I forgot to check R30, so I’ll go do that now. No soldered points are touching.

As @zgrav said

What about that joint on the switch - looks suspect. Doesn’t hurt to reflow them with some extra solder.

Reflowed, and am still getting a reading between the ground and output pads on the pcb.

 

[zgrav]

you know that the output pad on your pcb is -- somehow -- connected to ground. you need to use the schematic and look closely at your board to figure out where that is happening. disconnect the wire at S2 and see if the output pad is still shorting to ground. if it is, then the problem is on the board. if it is not, then the problem has something to do with the footswitch

 

[Coda]

you know that the output pad on your pcb is -- somehow -- connected to ground. you need to use the schematic and look closely at your board to figure out where that is happening. disconnect the wire at S2 and see if the output pad is still shorting to ground. if it is, then the problem is on the board. if it is not, then the problem has something to do with the footswitch

Disconnected S2 and the output is no longer grounding out. So the issue is with the switch. I’m going to rewrite the whole thing, and see if that help. If not, I can try a different switch.

 

[zgrav]

glad you made some progress isolating the source of your problem!

 

[Coda]

Is there a way to check for faults in the switch without swapping it for a new one?

 

[Coda]

Re-wired the switch and the output is shorted again. I’m gonna closely inspect the breakout board, and then replace the switch if it’s still an issue.

 

[zgrav]

there are 9 pins in a 3 by 3 layout

the middle row of pins connects either to the top row or the bottom row when you press the button.



so 2 connects either to 1 or 3
5 connects to 4 or 6
8 connects to 7 or 9

nothing in each column should connect to any other pins on the footswitch if there are no wires connected to the pins. it is 3 separate sets of switches.

one problem you have is that you already have a small circuit board soldered to your switch, so you need to figure out whether that circuit board also has connections between any of those pins even when no wires are attached. I have not looked at the layout for your pedal to see if that is the case, but the wiring diagram in your build docs only shows pins 1-2-3 and 7-8-9 being used, with no wires connecting any of those pins together. if your meter shows there are any other connections between the pins then the switch is bad or there is a problem in the small circuit board. 1-2 should be connected at the same time that 7-8 are connected, and 2-3 and 8-9 would be connected at the same time after you press the footswitch. there should be NO connection showing between 1-3 or 7-9.

 

[Coda]

there are 9 pins in a 3 by 3 layout

the middle row of pins connects either to the top row or the bottom row when you press the button.

View attachment 12575

so 2 connects either to 1 or 3
5 connects to 4 or 6
8 connects to 7 or 9

nothing in each column should connect to any other pins on the footswitch if there are no wires connected to the pins. it is 3 separate sets of switches.

one problem you have is that you already have a small circuit board soldered to your switch, so you need to figure out whether that circuit board also has connections between any of those pins even when no wires are attached. I have not looked at the layout for your pedal to see if that is the case, but the wiring diagram in your build docs only shows pins 1-2-3 and 7-8-9 being used, with no wires connecting any of those pins together. if your meter shows there are any other connections between the pins then the switch is bad or there is a problem in the small circuit board. 1-2 should be connected at the same time that 7-8 are connected, and 2-3 and 8-9 would be connected at the same time after you press the footswitch. there should be NO connection showing between 1-3 or 7-9.

I reflowed the breakout board and everything seems to be measuring good. I’m gonna re-assemble and see if it works.

 

[Coda]

I reflowed the breakout board and everything seems to be measuring good. I’m gonna re-assemble and see if it works.

All back together and the problem persists. Not seeing and shorts at either jack, but the pedal still does not work. When in bypass the gain control controls the volume of the bypass tone, and when engaged the pedal is silent. I think I’m giving up on this one. Another one for the failed pile…

 

[benny_profane]

Have you traced all connections from the output to ground? If you've ruled out the switch and the jack, there's a short on the board.