Beavis Breakout Box Woes

[Jdansti]

Actually, your one more step toward solving this mystery. My suggestion is to ignore the breakout box for now and focus on why your builds aren't working on the breadboard. There's something funky going on with either your breadboard or your circuits. Once we figure out what the problem is, you won't have to worry about it plaguing future builds.

After you have something working on the breadboard, we can reconnect that circuit to the breakout box and see what happens.

From here you should take the circuit you currently have on the breadboard and follow the troubleshooting instructions here: http://www.diystompboxes.com/smfforum/index.php?topic=29816.0 and post your results. Please also post the schematic you're using.

We'll get this figured out.

[deadastronaut]

@audiolife..here ya go, if this doesn't work then i am at a loss as to why...

try this...without your box.

from here.
http://www.home-wrecker.com/bazz.html

[audiolife]

thanks for that astronaut. I tried it and...it didn't work. I'm thinking maybe it is the breadboard...

I'm gonna take a break over the weekend and get a new breadboard to try. Here's to hoping! I'm sure I'll be back for more advice.

[deadastronaut]

hmmm re test the continuity (beep) onn your breadboard...

are you sure your wiring the jacks correctly?...this is very strange.

[audiolife]

Ok...tested the circuit again (the one astronaut provided).

Test 1: no breakout box. separate i/o jacks and battery power. CIRCUIT WORKED!

Test 2: signal going through breakout box, power through box as well. Nothing when engaged.

Test 3: used power from breakout box, used separate I/O jacks. CIRCUIT WORKED AGAIN!

This would mean that there is an issue with the switch, yes? If so, I'm going to rewire mine like yours and see if that doesn't solve the problem.

one step closer!

[deadastronaut]

yep wire it the same...it'll work.

your getting there...

[audiolife]

DeadAstronaut, could I connect the ground of the in jack to the middle lug on the switch, as the output is grounded there as well or would that mess something up?

[deadastronaut]

stick to how it is for now...lets get you going properly first... .... tried n tested.

[Jdansti]

I'm not sure, but he might be asking where to land the neg lead from his power jack. The Beavis Box has it going to the grounds of the signal jacks and then to lug #2 (left/center) of the switch. Your drawing has it going to the neg rail of the breadboard and lug # 5 (middle/center) of the switch.

Since he already has the ground from the output jack going to lug #5, he probably just needs to tie the grounds of the two signal jacks and the negative power jack together. Correct?

[deadastronaut]

yep...i always take the middle  lug ground (3pdt) to my in jack ground, so yeah that'll be fine. i never connect out jack ground (as in john lyons stuff) as its grounded on the box.




i always use that 3pdt wiring...its nice n neat and easily remembered...has the in left, out right.....middle ground.

[Jdansti]

That's the one I use. I agree that the symmetry of the signal wires makes it easy to remember.

[audiolife]

Ok, so I totally rewired the box according to DeadAstronaut's instructions. The only changes I made were I Grounded both input sleeves to the center lug on the switch.

I tested it, and while I do get a little signal when effect is engaged the 'effect' is hardly there, it's more or less attenuated clean signal. Also, the LED doesn't illuminate.

I tested the circuit with other jacks and battery power, and it worked fine.

As for troubleshooting this new wiring, the breadboard is getting power just fine on both rails and both sides. I'm guessing the problem is with the circuit I/O, b/c if it was a problem with the jacks I wouldn't get clean signal at all, right?

Also, I don't have my connections going directly to the breadboard, I have them going through a terminal strip. Here's how that's set up:

V+ : from DC jack - term. strip - breadboard
Ground: from DC jack - term. strip - breadboard
Circuit I/O: from switch - term. strip - bb

Basically every connection DA has going to his breadboard in the schematic he provided on my end is going through the terminal strip to the breadboard. I noticed you had 2 grounds on the out going to the breadboard, as well as the ground from the DC jack. As mentioned I have both jack grounds going to the center lug and the ground for the breadboard is from the DC jack, as it would be if using battery power.

I figured that was worth mentioning as it could be relevant.

I'm close, but still no cigar! 

[slacker]

I wonder if you have a missing ground connection somewhere. Do you have a connection between the ground terminal on the terminal strip and the ground pin of the the DC jack and connections between both audio jack sleeves and the ground pin on the DC jack? Doesn't matter exactly what order they're connected in but all those points must be connected together somehow.

[Jdansti]

+1

Has the LED ever lit?  Make sure it's not backwards.

In addition to what Slacker said, make sure the power is off and nothing connected to any jacks or the terminal strip, and check ground continuity with your meter as follows:

With one lead on the negative lug of the power jack, check for continuity, or lack of, at the :
1) guitar input jack sleeve-continuity
2) guitar input jack tip-NO continuity
3)output jack sleeve-continuity
4)output jack tip-NO continuity
5) center switch lug-continuity
6)negative/ground screw on terminal block-continuity

If all of that checks OK, we can look at continuities for both switch states.

BTW, do you have the "sag" pot wired to the circuit?

[audiolife]

@slacker:

Ah! I have the ground pin of the DC jack connected to ground of the terminal. I have the grounds of the jacks going to the center lug on the switch, but these 2 things are separate.

I'll jumper the audio jack sleeves to ground of the DC jack and see if that doesn't fix it.

If not I'll proceed with probing as suggested by JDansti.

Again, you guys are awesome. I'm really learning a lot about troubleshooting having fu#$&* this thing up so many times haha!

[slacker]

Fingers crossed that works, I think it's pretty much got to be it. Looks like you had them connected originally when you had your jacks wired wrong, guess it got missed when you fixed them.

[audiolife]

Ok, I jumpered the grounds and the engaged signal is a little stronger but still anemic and there is very little noticeable effect.

JDansti, I performed the continuity test on the grounds and everything was as you said it should be.

Should I perform the same test with power and the switch 'engaged'?

[AudioEcstasy]

could be a loose connection or solder point?

[Jdansti]

No need to do more ground checks at this time.  You're getting close.  I have few more questions:

Does the LED turn on and off now when you toggle the bypass switch?
Do you get a normal signal in bypass (LED off)?
Do you have the sag pot connected as shown on the Beavis schematic?
Is the SPDT switch only connected to the two designated screw terminals and nothing else?

[deadastronaut]

are you using sausages for wires?