led issues

[jlullo]

meanderthal,
do you mean disconnect the ground at the out jack? 

i disconnected that and it still gave me output.  with it disconnected, the pedal would only give me the led indicator if a plug was in the jack.

does this mean that is it?  all i'd have to do is use a plastic jack? if so, i'll be a happy guy

jonathan

[WelshWonder]

What's the possibility of good high res pictures so we can see exactly what's happening?

[Meanderthal]

 Yep, it sounds like yer ground is shorting thru the enclosure, so even one plastic jack should do it... I think...

[sfr]

All grounds from the board, and from the input and output jacks should have continuity with the enclosure.  At all times, whether a plug is connected or not.  It shouldn't matter if ground is making it to the enclosure through the output jack. 

The only connection that needs to be switched is the ground connection from the battery.  (In most cases, the black wire.)  This one wire should connect to the ring of a stereo jack.  (It doesn't matter which jack, in or out is fine.)   When a mono plug is inserted, this one connection will short to the same ground potential the rest of your ground connections are at and connect the battery.

Perhaps you've wired everything to the sleeve and not the ring of the stereo jack?  Perhaps the portion of the jack that connects to the ring is shorting to ground on it's own?  (I.E., w/o anything in the stereo jack, do you get continuity between the ring and sleeve?)

[jlullo]

alright... i just switched out both jacks to the plastic enclosed switchcraft jacks.... no difference..

without anything in the stereo jack, am am getting continuity between the ring and the sleeve.  i don't know why, because all i have wired there is the black lead from the battery snap.  all the grounds are on the shield, the tip is going to the switch.  what is causing the continuity?

[sfr]

If these are Radio Shack jacks, often times the act of tightening the nut on the jacks to put them in the box rotates the solder lugs in such a way that they touch each other.  Another possibilty is that the solder lug or the the bit that makes contact with the jack has shorted itself out with the enclosure.  The sleeve will of course make continuity with the enclosure as well (unless you're using isolated jacks - jacks where no metal touches the enclosure) and this will result in a short between the ring and sleeve with no jack inserted.

Might be worthwhile to remove everything from the enclosure and make sure that something shorting out isn't causing your problem.

Also make sure that battery snap isn't touching the enclosure - I've never had a problem with this with an actual battery attached, but when troubleshooting a problem, I didn't realize that the battery snap (sans battery) was lying against my enclosure, and I spent a while trying to find a short that was non-existant.

As far as what's causing the continuity, short answer is a direct electrical path between the two points.  Could be a stray wire/solder blob shorting the lug for the ring to the sleeve of the pedal, could be something mis-wired (Might be worth pulling a stereo cable into one of those jacks you have and making sure it connects in the fashion you expect.) , could be worn insulation on the ground lead to the battery shorting out against the enclosure - at this point it's hard for anyone to say; it's easy to identify a problem of this sort (continuity where there shouldn't be) but without seeing things, it's hard to say what's causing that problem.  A pic would probably be helpful at this point.

[Meanderthal]

 Yep, (thought we had it licked that time) I agree, at this point a pic would help...

Odd that disconnecting the output ground seemed to work, but plastic jacks didn't... I'm stumped now...

[jlullo]

alright... i'm making some headway.  i removed the jacks from the enclosure with everything still wired up, tried it- the led won't come on unless i have a cable in the jack.  also, with the jacks out of the holes i drilled, if the jack is touching anywhere the enclosure is powdercoated, the led won't turn on, but as soon as you slide it down to bare metal, it will.

here are some pics for you.  it's extremely messy, because i've taken apart and put back together this pedal about 5 times...






the resistor connecting to the LED looks like it is touching the enclosure, but it's not.
does this help at all?

jonathan

[jlullo]

i also think i know why this is happening now, and never was before.. i always get my enclosures from kirk @ pedal parts plus.  i used to have him drill them for me, and he drills them first, and then powdercoats them.  now, i've started drilling them myself- the holes are bare and not coated.

should i maybe try wiring this up and soldering all grounds to the pcb?

[jlullo]

alright fellas, i just "fixed" this, and it works great now.  I took a super thin piece of electrical tape, and wrapped it around the part of the jack that touches the hole in the enclosure..... popped the washer and nut back on and it is working fantastic now.  is there something i can do in the future to avoid this, or am i going to have to rig everything when using the jack as the star ground?

[sfr]

Whether or not the jack is insulated from the enclosure shouldn't matter - in fact, if you have no connection from ground to the enclosure, (through the jacks or otherwise) you defeat the purpose (shielding) of having the a metal enclosure.  The circuit grounds and jack grounds should basically *always* be in continuity with the enclosure regardless of whether power is switched or not.  The battery ground is the *only* thing that should no longer connect if the jack is pulled out of the stereo plug.



This is the jack you're using for power switching? 

On the switchcraft jacks, the "diagonal" tab (in the bottom in this picture) is generally the sleeve, I believe.   This is the connection that's always grounded to the chassis - where all your common grounds should go if you're grounding them at this jack.  (You could of course ground them all at the same lug on the mono jack at the output)   The battery needs to go to the "ring" not the "sleeve".  This is the "middle" part of a stereo jack.  (If you don't have a stereo 1/4" jack, look at the end of a a headphone cable to at least *see* what I mean.

Easy way to test jacks is to plug in a stereo (not mono, as this will short out two of the connections!) plug into your jack in question, and use the multimeter to test the connections between the other end of the cable and the solder lugs.  If you don't have a stereo plug, insert a mono one, and probe between the lugs and cable and find out which one is the tip (pretty self evident - only one lug will connect here ) and then identify which two are the ring and sleeve.  (These two will short out with a mono plug in the jack) Remove the cable, and these two will not short out anymore - the sleeve's lug is the one that connects to the outside of the jack.  (Easy enough if you've got a metal threaded jack, otherwise you sort of need to reach inside the jack to probe for this.)

[jlullo]

sfr,
i checked again using your dmm method, and that diagonal lug (with the rounded edge) is indeed the ring, which is where i have my negative lead of my battery clip.  i am positive that the other lug is the shield lug, and have tested it a bunch of times...

[sfr]

Are you sure?  How did you test?  (These two connections will short out w/ a plug inserted) Are we clear on "sleeve" and "ring"?  Ring is the "middle" connector on a stereo plug, but will connect to ground if a mono jack is inserted, since it doesn't have one.

Stereo: http://vfwtech.com/Liquid/Tips_Tricks/Audio/trs.gif
Mono: http://vfwtech.com/Liquid/Tips_Tricks/Audio/ts.gif

You'll also notice the mono jack you're using on the other side has that same little diagonal tab, and it doesn't have a ring, because it's mono - just tip and sleeve. (Switchcraft plastic jacks put the tip, ring and sleeve in the same spot on all the jacks.) 

I'm can't look at the jacks I have, because I'm at work, but I'm looking at switchcraft's PDF files on their site, and it's showing that diagonal tab as being the sleeve on every one of their enclosed jacks.

http://switchcraft.com/products/pdf_files/jack-87_schematic.pdf

[sfr]

Also, the fact that removing or insulating the jacks from the enclosure causes the pedal to operate as expected (inserting a jack powers things up) also points to the ring and sleeve being switched on one of the jacks - the battery connection is no longer going to ground when not being in the enclosure (because the sleeve is no longer physically connected to ground via the enclosure) and inserting a plug connects the circuit grounds and the battery ground and completes the circuit.  I think you've been switching "ring" and "sleeve" on the stereo jack everytime you wire this up.  (Obviously you've got the "tip" connection right though, or you'd get no output!)

[jlullo]

sfr,
alright i switched the two that i thought were sleeve and ring... now, the led will turn on and off only when a cable is in the jack.... but, there is no ouput!

by the way, i'm now confusing the hell out of myself 


edit:
now i've wired the pedal exactly how it appears in the schem you sent over.  now, the effect will not turn on, but the bypassed sound turns on when the switch is engaged.  led turns on and off when it should

[sfr]

I'd say there's the possibility that you swapped the tip and sleeve somewhere along the way, but if you're getting any sound out at all, in bypass or not, then I'd imagine that's not the case. (Not that it doesn't hurt to check - plug a cable into a jack, and make sure the tip and sleeve don't have continuity, both in bypass and not.  Try the other jack to,  It only takes a second. )   

Perhaps a connection just got knocked loose along the way.

I'd measure the voltages on the board itself - if you're getting voltage anywhere you expect it (around 9V at pin 8 of the IC, or anywhere else connected to the 9V line) then you know you're fine, getting voltage to the board.  (Obviously the LED, which appears to be connected to the DC jack, is getting power because it lights up) 

Obviously, in bypass, the tip of the input and tip of the output are connected, because you hear something.  Now you want to check that signal is making it in, and making it out of the board.  Since I believe you said this was working before, we'll start with the assumption that it's something with the offboard wiring and not the board itself.

I'd take the meter, plug a cable into the input, and check that the tip of the cable makes it to the "input" on the board - I'd probably follow it to the leg of the first component. Click the switch - it should only make it that far when the pedal's not in bypass.  (In bypass, it goes directly to the output jack tip.)   Do the same with a cable in the output jack - tip of that cable should go to the out on the board.  And not to ground or anywhere else. )

If you find that one of these connections isn't happening, than start following wires - it could be something wired the wrong place on a jack, or fallen off of the switch.  Check your switch wiring too, it's really easy to accidently short one lug to the ground lug by accident, if you have a little extra wire hanging around there.

[mattpocket]

I'd say you pretty much exhausted looking at the jack, the poor guys soldered and desoldered about 10 times already! haha

When I load my enclosure I make a ground connection to the output jack through the enclosure (i.e. not using isolated jacks) so that shouldnt be a problem... do you have a wire going from the sleeve of the input jack to the sleeve of the output jack? If you wish to make this ground connection through the enclosure (see tonepad wiring instructions) then you need to emit the physical connection of the wire, otherwise you've grounded it twice and that will cut your output...

The fact that when you tape one of the jacks up the LED lights up suggests that your jacks arent insulated. And that when you do this, you dont have a ground to the output jack, which is why you wouldnt get any output.   

I dont know if that helps, but I had a problem similar to this before and it was down to the jacks not being isolated and/or double grounding the input/output jacks.

I'd start looking at other things like your switch wiring and any shorts you might have on the board... Did you insulate the board from the enclosure? (i.e. so that any solder is NOT touching the walls of the enclosure)

I'm fairly new to this myself, so dont take my answer as gospel. I just thought it might pay to give a reply of my experiences in the hope that it might create a spark to shed light (no pun intended) on the problem...

Matt

[sfr]

I'd say you pretty much exhausted looking at the jack, the poor guys soldered and desoldered about 10 times already! haha

Which is why I directed his attention there again - we knew signal was coming out of the pedal before he fixed the ring/sleeve mixup problems that were giving him troubles with the LED.  Assuming that's all he changed, it may very well be that the problem is there again.  However, as I said, given that he's getting output in bypass, that is probably not the case.
But plugging a cable into the pedal and checking for shorts betwen ground and tip will tell him if he's shorting the input or output to ground,  which will help him trouble shoot, and takes about 30 seconds.   

Most of my advice was simply to follow the signal path between the jacks and the board - since he said the board was working before, we can probably assume that's still working - if he's not getting signal output through the board, it means either active components are getting no power (which is why I briefly mention checking for power on the board), or the signal line is not making into or out of the board. (Which is why I mentioned checking continuity between the tip and whereever it should be going to or coming from on the board.)  Or that the input or output signal is getting connected to ground by accident. (Which is why I mentioned checking if tip and sleeve are shorted at the input or output when the pedal is not in bypass)  Probing the jacks is simply an easy way to identify which of these problems it may be, and which side of the effects board it's occuring at - input or output. 

When I load my enclosure I make a ground connection to the output jack through the enclosure (i.e. not using isolated jacks) so that shouldnt be a problem...

Correct, and in fact you want a ground connection to the enclosure *somewhere*, otherwise the enclosure provides no shielding. 

do you have a wire going from the sleeve of the input jack to the sleeve of the output jack? If you wish to make this ground connection through the enclosure (see tonepad wiring instructions) then you need to emit the physical connection of the wire, otherwise you've grounded it twice and that will cut your output...

While making multiple ground connections isn't always the best practice, and can lead to ground loop noise and such (although we can get away with a lot more in a stompbox build compared to a tube amp build) grounding something twice should not result in decreased output, as long as all the things you've connected to ground are things that are supposed to be connected to ground.  If you start connecting signal to ground, or signal to ground through a resistance, then yes, volume will suffer, but wiring multiple connections between points that are already at ground potential should not change anything.

The fact that when you tape one of the jacks up the LED lights up suggests that your jacks arent insulated. And that when you do this, you dont have a ground to the output jack, which is why you wouldnt get any output.   

Good thinking!  This could very well be the problem - I didn't think to ask if he un-insulated the jacks again.  In his earlier pictures, there appears to be a cable running from the sleeve connection on the output jack to ground, however, if the jacks are still insulated, and the this wire has been removed, then yes, there is no ground connection on the output jack, and things could be wierd. 

However, given that he's getting output in the bypass mode, I would assume that's not the case. Its worth looking at, because it only takes a second though - make sure you're sleeve connections have contact with the other ground points in the build.

I'd start looking at other things like your switch wiring and any shorts you might have on the board... Did you insulate the board from the enclosure? (i.e. so that any solder is NOT touching the walls of the enclosure)

This is always a good point to mention.  Also make sure the board is clear of any un-protected connections like the indicator LED legs, and pot tabs. 

That's pretty much it - we know the signal is making it through in bypass, and power switching seems to be working, so his jacks are probably wired correctly now, and at least half his switching is.  So the trick is to find out if it's a no power situation, a short to ground, or a broken connection.  Obviously checking the easy stuff and making visual inspections will tell you this, but following signal path with a multimeter, and checking connections will tell you a lot, and save you from having to continually redo connections you *think* might be the problem, because you'll be able to narrow the problem down to a certain set of possibilities.

[jlullo]

guys,
thank you so much for helping me out with this.  i got really frustrated last night, so i'm just going to take a day or two off from this and get back to it on the weekend.  i'll report my findings as soon as i actually find them

sfr, thank you so much for your patience and persistance with helping me to figure this out.  it doesn't go unappreciated!!  as well as everyone else!