How to build and Use a Basic Testing Rig

[Om_Audio]

Thanks man!
C

that ^^^ is awesome ! a true pedal builders build. love the look.
even with custom cap calculating on the workbench !

[Stomptown]

Nice,I sed the alligator clips and for an audio probe,I just grab typically a small screwdriver and clip it to the audio out.dual purpose and it works well.is that a volume pot? I'd love a way add the pots without soldering them until I'm ready to box it.

Good Idea! And yes that's a volume pot. I just made the wires extra long so I can remove it later and cut down to the length I need for the enclosure. I would love to have a bank of pots that I could wire up to terminal strips so I could avoid soldering the pot on for testing. Maybe a test rig in a larger enclosure with lots of pots, an led and true bypass wiring!

[AllenM]

Following Jacob's guide I went and built a testing rig. Man this thing is handy! Added a toggle for the probe / output gator clip.





And of course my quality control supervisor had to sign off on the build...


AllenM

[jkokura]

That looks awesome Allen. Curious what you got those black hole things for the clips...

Jacob

[AllenM]

I found those at a local mom and pop electronics shop and use them to plug "extra" holes in enclosures. I did a quick google search "plastic hole plug" and found this

http://www.mouser.com/catalog/catalogusd/645/2667.pdf

The type B look to be similar. I also have some that are metal for larger holes.

For the above project I drilled a hole in the plug big enough to run the wire thru.

AllenM

[das234]

Ok.  I'm onto this project.  I drew up my own (crummy) little diagram for this so I can build it.  Am I correct that the enclosure provides the ground connection from one jack to the other so I need a conductive enclosure to make that happen?  I have an old cigar box laying around I was going to use but I don't think that will work.  Or can I just add a wire somewhere to fill in the missing link?

[Haberdasher]

yes, you're right- the metal enclosure automatically grounds the other jack.
my test box is pvc or some other plastic.  I just ran a wire from the grounded sleeve to the other jack's sleeve and that worked fine.

[das234]

EXCELLENT!  I knew something!

[Outtagetme]

Hi everyone, this is a very interesting post!!!
I'm planning to build my own testing rig, along with an audio probe, and I was wondering if I could use a RCA plug as a probe, since I don't have any spare multimeter tip. I have an old RCA connector, with a 3-pin end on one side (red, black and yellow) and 1-pin on the other end. Maybe I could use one of those wires (along with the connector) for my audio probe, what do you think?

Ciao,
M.

[das234]

It seems to me those plugs would be awfully difficult to probe a PCB accurately.  You'd probably have better luck making a probe from a piece of solid core wire thick enough to hold its shape but thin enough to get into the tight spots, maybe 20g-24g.   

[das234]

I thought I'd share my test rig that I built using an old cigar box and a lot of helpful tips from this thread.  You may notice I have not installed a test probe.  I haven't needed one yet (knock on wood) but I'll solder one in if the time comes that I need to troubleshoot something with it.

[jimilee]

Those pictures are tiny, got a better one?

[gingataff]

click on it

[das234]

Those pictures are tiny, got a better one?

That's weird.  I took the picture on my phone and uploaded it just like I did with the pfannkuchen pictures and those were fine.  I'll see what I can do to fix it.

[das234]

This is better. You can see it's got plenty of room to tuck away the leads inside the box for storage.  And the enclosure cost me zero dollars.  That's a good price.