New testing rig

[Jabulani Jonny]

Hey Jacob,
If possible, can you take a look at the proposed wiring for a new testing rig to make sure I'm thinking about it correctly.  My primary question has to do with the DPDT switch I'm using to select between the 1/4" guitar in and the Oscillator In (out).  That may be confusing.  Here's what I'm trying to do:

I'm basically blending the Beavis Audio Bread Board testing rig seen here:  http://beavisaudio.com/bboard/images/io_diy.jpg  with your testing rig above.

As you mention, I may need to have the osc output grounded when i'm using the 1/4" input and the 1/4" input grounded when I'm using the oscillator.  Does that make sense?  Not sure if I actually need to ground the 1/4", but thought it couldn't hurt. 

I'm also implementing a testing probe, which I already have separately, but wanted to make it part of the box.  I've put in a switch to let me interrupt the signal from the circuit with the probe. 

Can you take a look at the attached and let me know if that looks like it should work?  My question is whether the Osc signal will be affected when it has two signal paths, one to ground and one to the output, when it's selected via the switch.  Sorry if that's confusing.  Thanks for the help.



Uploaded with ImageShack.us

[jkokura]

I'm not at home, but I think the way you're have that DPDT should work, but there's no grounding happening there.

What you should do is connect one pole's common to the 3PDT, and the other common to ground. Create an X with the outside lugs, so that on throw one, one is grounded and the other is not, then it flips when you switch throws. Then, attach the oscillator's out to one throw on the 3PDT connecting pole, and then connect the Guitar input jack to the other throw. Then, the'll each be grounded when bypassed, both of them.

I'm not really able to make a diagram where I am right now, but if you're really struggling to get what I wrote up there, then give me a heads up as to what's confusing and I'll try and give you a hand.

Jacob

[Jabulani Jonny]

If I'm following you, you mean like this?:

[jkokura]

Yeah, that'll work. You can switch gnd and 3pdt and it will work the same too.

Jacob

[Jabulani Jonny]

Awesome.  Thanks for that.


Also, I had another question regarding power supply to the board and the various other parts of the pedal.  I basically need to power 3 things, the tiny tester PCB, a power terminal on the strip and the LED.  The DC jack lug only has room for two wires.  Does your PCB pass power at all?  I saw on your testing rig, which looks like a vero layout, that it does pass power to the LED, but the PCB doesn't look like that's the case.  Any thoughts on the best way to provide power to those three items, with only soldering two wires to the DC lug?  

Many thanks for your help.  

[Guitafuzz]

  hi jabulani  i have a cuestion, what is the function of the spdt switch labeled sw1 & sw2 ?

[Jabulani Jonny]

Hey GFuzz,
That is wired to the SW1 & SW2 terminal poles on the side terminal strip for the circuit.  This is for circuits that may have a switch to incorporate modulation or some kind of change in the circuit. 

Also, if you're thinking about implementing Jacob's Tiny Tester board, which I highly recommend, I would definitely go with the higher cap values to lower the sine wave pitch.  I went with stock values and it's a very annoying tone.  Although, I can't imagine a straight sine wave tone at any frequency wouldn't be annoying. 

Hope that answers your question.  This has been fantastic to have.  I've used it on each build since I've completed the testing rig.  All 2 of them.   

[tenwatt]

Any chance of getting build docs for this?  I REALLY want to build this.