SOLVED ONLY works with cable plugged into input jack.

This is a weird one, and I can't find the information I'm looking for anywhere. I built an Oasis (Dunes) pedal. It only turns on when it's plugged into my 1 Spot Current Reader/Cable Tester. I put it on my board, which uses isolated power (Truetone 1 SPOT PRO CS12 12-output Isolated Guitar Pedal Power Supply), and it didn't power up. Then I tried it by itself using a 1 Spot 9v. Still, it didnt power up. I put it back on the 1 Spot Current Reader/Cable Tester, and voila, like magic, it turns on.
One more quirk: It only works if a cable is plugged into the input jack. (Of course, I did this with my other experiments, but it only powered up with the 1 Spot Cable Tester/Current Reader.)
 
Solution
Definitely a ground issue then. Loss of ground specifically, since the pedal (only) works when it has a secondary ground path.

I'd look closely at your DC jack. Maybe the center pin isn't the correct diameter or is damaged in some way? Unless that's a genuine Lumberg that style of jack is known to be troublesome.

If you have a DC cable (male/male or male/female) plug it into the DC jack of the pedal and check for continuity between the center barrel of the opposite end of the cable and the sleeve of your 1/4" jacks.

If you don't have a cable or DMM to make the measurement my blind guess would be to replace that DC jack.
Ground issue?
By not working, do you mean doesn't turn on, doesn't pass audio, passes noise?
Thanks for replying!
It only passes audio when in bypass. When the pedal is "on", it doesn’t light up or pass audio, except for when I plug it into the 1 Spot Cable Tester/CurrentReader. I thought it might be a ground issue, but I can't find any place where that might be occurring. And why would it only work with one 9v supply and not any others? Weird!
 
Are you getting a good ground? Check that the inside of the enclosure has continuity with the negative power lug, as well as the ground on the jacks.
 
If you plug your 1Spot into this pedal with absolutely nothing else connected, no 1/4" cables, just the pedal and a DC power supply, does the LED light up?
 
Definitely a ground issue then. Loss of ground specifically, since the pedal (only) works when it has a secondary ground path.

I'd look closely at your DC jack. Maybe the center pin isn't the correct diameter or is damaged in some way? Unless that's a genuine Lumberg that style of jack is known to be troublesome.

If you have a DC cable (male/male or male/female) plug it into the DC jack of the pedal and check for continuity between the center barrel of the opposite end of the cable and the sleeve of your 1/4" jacks.

If you don't have a cable or DMM to make the measurement my blind guess would be to replace that DC jack.
 
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Solution
Definitely a ground issue then. Loss of ground specifically, since the pedal (only) works when it has a secondary ground path.

I'd look closely at your DC jack. Maybe the center pin isn't the correct diameter or is damaged in some way? Unless that's a genuine Lumberg that style of jack is known to be troublesome.

If you have a DC cable (male/male or male/female) plug it into the DC jack of the pedal and check for continuity between the center barrel of the opposite end of the cable and the sleeve of your 1/4" jacks.

If you don't have a cable or DMM to make the measurement my blind guess would be to replace that DC jack.
Wow! Great advice! Thanks, Robert. I'll check it out and post when I fix it.
On a related note, I have purchased genuine Lumberg jacks before, as well as knock-offs through Tayda. Are you saying that the knock-offs are prone to issues? (I guess that shouldn't surprise me.)
 
Are you saying that the knock-offs are prone to issues? (I guess that shouldn't surprise me.)

There have been quite a few reports of the knock-offs failing in one way or another.

Out of the hundreds I've used I think I've personally only had one or two defects and I continue to use them but there are enough reports on the forum to be cautious. My builds are almost all prototypes that never leave the shop (and end up in "the box") so long term reliability isn't my primary concern.
 
There have been quite a few reports of the knock-offs failing in one way or another.

Out of the hundreds I've used I think I've personally only had one or two defects and I continue to use them but there are enough reports on the forum to be cautious. My builds are almost all prototypes that never leave the shop (and end up in "the box") so long term reliability isn't my primary concern.
Good to know! I've had a couple where the DC cable had to be positioned just so or else there was no connection.
On a very happy note, I tested it and found that the pseudo-Lumberg jack was faulty. I replaced it and the pedal fired up right away. Thanks, Robert and everyone else who chimed in!
 
This was the last time I used one of the Tayda ones. Pushing in the dc plug pushed the contact right out of the housing. 😂

The one I remember had a weird little metal tab inside the barrel of the jack that prevented a plug from being inserted. It didn't fail, it was never usable to begin with.

Aside from that I think I've had one wear out from normal use, but otherwise been fairly lucky.
 
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