Building a stripboard LPB-1 based on DIY-Layout.com design

[LonePhantom]

Hi all, after successfully finishing off my first custom pedal build based on a cheap Daphon SD-1/TS-9 type overdrive where I modified the circuit and rehoused it, I'm having a go at building a pedal from scratch.

I found the diy-layout.com site, and thought that I would give the LPB-1 design a go as my first pedal build: http://diy-layout.com/25


I've built the circuit, and I believe everything is ok on that, run the connectivity meter over to make sure all connections are good.

I looked for a diagram of how to wire up a true-bypass switching system, and have used this one here: http://www.beavisaudio.com/techpages/SchematicToReality/


I've wired the output of the circuit (the spot on the pot) to the bottom right point on my switch, input to the center point, ground to the sleeve of the output jack, the +9Volt to the corresponding point of a battery snap, and added the LED with the resistor. I've followed the rest of the diagram to wire up the remaining jack spots, etc.

When I power up the circuit with a battery the LED will turn on and off with the switch, but there is no sound. I'm hoping that it's just an issue with the wiring and not the circuit. I was at least expecting that with this true-bypass wiring that I would at least get a signal through to the amp when bypassed, but there is nothing.

Should this diagram be right to follow to get the LPB-1 design to work? Is it perhaps that I need to ground the output jack sleeve to the enclosure, would that affect the signal when bypassed too? I haven't got anything in an enclosure yet, but I can install a ground to it before I install the circuit if need be.

Thanks in advance.

[PRR]

> I need to ground the output jack sleeve to the enclosure{?}

Yes, at least to other system grounds.

The enclosure is not essential to "work", but helps block outside buzz, radio stations, and careless feet.

> would that affect the signal when bypassed too?

The jack needs to ground with the input; else you don't have a complete circuit from in to out.

In the plan shown, the circuit board only gets signal and power ground via that meandering ground wire which hits the out jack. Make contact through that path, and you may find life in both modes.

> I can install a ground to it before I install the circuit if need be.

Clip-leads are your friend. You could clip the grounds together a heck of a lot faster than you can write a posting. Meanwhile, a hot soldering iron can quick-tack a ground jumper to prove/disprove your suspicions.

[LonePhantom]

Thanks for your advice. I actually went and re-did the wiring, this time based off the diagram on General Guitar Gadgets 3pdt wiring. Still no luck though.

Grounded between input and output. Continuity meter says all good. Grounded to enclosure too. Again just the led turning on and off. No sound at all.

Would it be worthwhile me removing the input and output wires from the switch and linking the two points with wire to make sure my bypass is all good? That way I can eliminate the circuit itself for troubleshooting?

Thanks again.

[petemoore]

Would it be worthwhile me removing the input and output wires from the switch and linking the two points with wire to make sure my bypass is all good?
  Be quick with the heat and let the switch cool between applications.
  Sure, also the DMM can look for continuity 'thru' for signal path around the jack/plug/switch areas, into the PCB, and the out-end the same way, check for grounded signal path everywhere while there.
  That way I can eliminate the circuit itself for troubleshooting?
  That'll work, did that a few times, pretty sure the wiring can be straightened out and debugged otherwise, but that's one quick way to see if signal gets through.
  Jacks that have 3 wires attached...
  Switch that is rotated 1/4 turn [and so needs rotated 1/4 turn for the lugs to assign correctly..
  These are sorta common mistakes and you have work through one each, it's only obvious when you ''see'' it..
  I didn't catch any circuit-pin voltages of active components, this will tell if the circuit has a chance to work.

[LonePhantom]

Thanks for that. What did you mean by switch rotated a 1/4 turn? Are you supposed to engage the switch somehow?

[blooze_man]

My first LPB had a backwards transistor. Also try removing the switch from the circuit and use a continuity tester to check the switch itself. Once in a while you can get a bad switch or you can ruin them on accident if your not quick with your soldering.

[LonePhantom]

My first LPB had a backwards transistor. Also try removing the switch from the circuit and use a continuity tester to check the switch itself. Once in a while you can get a bad switch or you can ruin them on accident if your not quick with your soldering.

Ah thanks for that. I went and checked my switch with a continuity meter (with the wires still hooked up though, not sure if that is an issue), and it seems that one row of lugs are dead switching back and forth. I checked a spare one I had (thankfully), and noted how the switch worked. Without removing the wires am I safe to assume that I've probably killed the switch I have wired up, or should I disconnect everything to really check this?

Thanks again all for your help.

[Perrow]

Thanks for that. What did you mean by switch rotated a 1/4 turn? Are you supposed to engage the switch somehow?

I think he means you should check that your 3pdt is aligned correctly. If you've got it 1/4 turned you'd be out of luck.

I think if you could post an image of your project it would help us help.

[blooze_man]

Ah thanks for that. I went and checked my switch with a continuity meter (with the wires still hooked up though, not sure if that is an issue), and it seems that one row of lugs are dead switching back and forth. I checked a spare one I had (thankfully), and noted how the switch worked. Without removing the wires am I safe to assume that I've probably killed the switch I have wired up, or should I disconnect everything to really check this?

Thanks again all for your help.

I'm sure the orientation of the switch is fine as the LED is lighting up. Try switching the old switch with the new switch. tinning your wire and the lugs of the switch really help to make a quick and clean solder connection.

[LonePhantom]

Definitely should be aligned the right way. If the switch is sitting on it's side the holes in the lugs are facing up. Checking on the continuity meter the lugs are two lots of 3 going across.

I'll post a photo on later tonight if I'm still having issues. I'll try my other switch first.

Thanks all.

[LonePhantom]

So I've rewired in a new 3PDT switch, and it's all good still on the continuity meter.

I've used the diagram from general guitar gadgets:
http://www.generalguitargadgets.com/diagrams/switch_lo_3pdt_tb_battery.gif?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a

My ground from the input to the output jacks reads on the meter as well. I'm assuming that this means ground all is good all of the way through the circuit. I've essentially wired one wire to the strip board as per the diagram at the top of this thread, and connected three more wires for the jacks, and the switch.

When I try to measure the input and output tips I get nothing though. When I check the connections from input to  switch, and output to switch they are fine.

I get no signal when bypassed or engaged, LED lights on and off when switch is engaged and disengaged though. Bypass wire reads on continuity meter too.

Is there anything that I could be missing?

[LonePhantom]

Here's a pic, dunno if you can make out much here though.

Thanks again for all your help guys

[LonePhantom]

Anyone please have any ideas as to what I am missing?

[blooze_man]

No signal when the effect is on and bypassed makes me think something may be grounded that is not supposed to be. From what I can see in the pic, everything looks fine.

[JKowalski]

Check to make sure there aren't any bridges (stray wire, stray solder) on the jack leads? Or anywhere else?

[LonePhantom]

OK thanks, I thought things looked to be in place. I'll have a go at re-doing a few wires, although they all look pretty clean. I may have some bad solder joints though. I only ever have time to work on these things when it's in the evening, and I'm always tired due to my little son who keeps us on our toes! I may very well be doing some poor soldering that isn't noticeable to tired eyes!:lol:

[LonePhantom]

Am I right to think that with a working circuit I should be getting a beep from my continuity meter if I touch the input and output jack tips?

Every connection shows continuity except going from the input tip to output tip.

[linny1982]

maybe a dumb question but have you done the trace cuts?

[LonePhantom]

Yes trace cuts are done. Regardless of that I should get a signal on bypass anyway though?

[LonePhantom]

Also, is there any way of killing a TRS jack? I thought that they were pretty simple, and not something that would break easily, but I've been wrong before.