Page 1 of 1

Really strange problem

Posted: Sat Apr 27, 2013 11:40 am
by pulsewidthmod
So I built the distortion 2 and wired it up. Checked to make sure that the stripboard had no solder connecting traces that shouldn't be connected.

I connected my drum machine up to the pedal and then used my audio probe to debug.

It has a really strange issue. i turn the 3pdt off and probe the input jack .. the output jack and i'm getting sound as i should.

WHen i turn the switch on, the led comes on. I"ve got the ground connected to the output's sleeve. When i probe the input, no sound comes thru. This is the first point in the circuit... I don't understand what is going on.

:?:

:idk:

:?:

:facepalm:

WTH?

What would turn the sound off at the input? I don't understand this at all.

Re: Really strange problem

Posted: Sat Apr 27, 2013 11:45 am
by DannDubbleEwe
Try grounding the input to the output? Maybe? :idk:

Re: Really strange problem

Posted: Sat Apr 27, 2013 11:53 am
by pulsewidthmod
I did .... i'm checking the switch right now

Re: Really strange problem

Posted: Sat Apr 27, 2013 11:55 am
by pulsewidthmod
well, the 3pdt is fine .. IDKWTH the problem is

Re: Really strange problem

Posted: Sat Apr 27, 2013 11:57 am
by DannDubbleEwe
Maybe a switched ground and signal wire? Pictures are always helpful! Is it mounted in an enclosure or free floating? I've been debugging in the past only to realize the jacks need to be mounted to metal so they ground out. Otherwise BOOP nothing.

debugging pedals = the most frustrating thing EVER.

Re: Really strange problem

Posted: Sat Apr 27, 2013 12:08 pm
by Dr Satan
Sounds like your input signal is shorting to ground.

Re: Really strange problem

Posted: Sat Apr 27, 2013 12:16 pm
by Dr Satan
DannDubbleEwe wrote: I've been debugging in the past only to realize the jacks need to be mounted to metal so they ground out. Otherwise BOOP nothing.
If you ground the circuit without relying on the enclosure as a ground path, you won't have this problem. It's not difficult to run a wire between the input and output ground lug and then another wire to the ground plane on the board. You do this and you don't need an enclosure, also if you use isolated jacks(the plastic ones like a lot of pedals and Marshall amps use) you have to run a wire between the jacks and the ground plane otherwise it won't work, or you'll just have tons of noise.

Re: Really strange problem

Posted: Sat Apr 27, 2013 12:33 pm
by pulsewidthmod
i've got the board's ground going to the ground lug on the power jack.

I've got the input and output ground going to the ground lug on the power jack

i've got the 3pdt ground going to ground

switch is wired like this:

3PDT TB Wiring.jpg
3PDT TB Wiring.jpg (20.95 KiB) Viewed 2136 times

Re: Really strange problem

Posted: Sat Apr 27, 2013 1:00 pm
by Dr Satan
pulsewidthmod wrote:i've got the board's ground going to the ground lug on the power jack.

I've got the input and output ground going to the ground lug on the power jack

i've got the 3pdt ground going to ground

switch is wired like this:

3PDT TB Wiring.jpg



Okay, so if all that is well and good, move to the next point in the signal chain. Which layout did you use? What schematic are you working from?

Re: Really strange problem

Posted: Sat Apr 27, 2013 1:10 pm
by eatyourguitar
pulsewidthmod wrote:WHen i turn the switch on, the led comes on. I"ve got the ground connected to the output's sleeve. When i probe the input, no sound comes thru. This is the first point in the circuit... I don't understand what is going on.

What would turn the sound off at the input? I don't understand this at all.


only one thing I can think of, ground is connected to the input. it is only possible to hear the audio from your tone generator + probe when the signal you are probing has a resistance to ground R > 0. when you wired the 3PDT switch for grounded input, that means grounded effect input, not grounded input jack tip.

it is also possible that you have sleeve and tip reversed on one or both of your jacks but I would guess it is most likely your 3PDT wiring. I suggest you disconnect power, put the probe and drum machine away for a minute and test resistance from each sleeve and tip to ground. you should have 0 or R < 10 Ohms from sleeve to sleeve, sleeve to power ground, sleeve to board ground, sleeve to 3PDT ground. you should have R > 10K from input tip to sleeve, tip to board ground, tip to power ground, tip to 3PDT ground etc... you should also have very high resistance from input tip to output tip when the effect is not bypassed and very low resistance R < 10 Ohms when in bypass.

on a side note about how trouble shooting non-working pedals is frustrating, I disagree. knowledge it power. practice is how you get experience. I can troubleshoot prett fast cause I do things in order. divide and conquer

Re: Really strange problem

Posted: Sat Apr 27, 2013 2:21 pm
by pulsewidthmod
eatyourguitar wrote:
on a side note about how trouble shooting non-working pedals is frustrating, I disagree. knowledge it power. practice is how you get experience. I can troubleshoot prett fast cause I do things in order. divide and conquer


I agree, it's just the timing. I"m taking a break for a few hours. I'm literally making these pedals for a few reasons ... knowledge, need, and interest.

I need to record guitar tracks for my album and my husband needs some good effects for bass too.

thank you for the help, i'm gonna give the pedal a look in a few hours. :)

Re: Really strange problem

Posted: Mon Apr 29, 2013 2:18 am
by DannDubbleEwe
Dr Satan wrote:
DannDubbleEwe wrote: I've been debugging in the past only to realize the jacks need to be mounted to metal so they ground out. Otherwise BOOP nothing.
If you ground the circuit without relying on the enclosure as a ground path, you won't have this problem. It's not difficult to run a wire between the input and output ground lug and then another wire to the ground plane on the board. You do this and you don't need an enclosure, also if you use isolated jacks(the plastic ones like a lot of pedals and Marshall amps use) you have to run a wire between the jacks and the ground plane otherwise it won't work, or you'll just have tons of noise.


:facepalm:

:hobbes: Dannster feels teh stoops. :hug:

Hope you get this sucker up and running! LEARNING is wonderful, and everyone here is wonderful.

Re: Really strange problem

Posted: Mon Apr 29, 2013 12:18 pm
by Dr Satan
Don't feel bad man, the simple shit is the hardest stuff to see. On more than one occasion I've spent more time than I should have hunting problems that were ultimately the result of some dumbass forgetting he disconnected the input signal...(looks at self) DOH!