Re: GPCB Swaw help! FIXED

[jimilee]

I'm officially stumped, I built the swaw and it wont quack.. I get clean signal, but there a nice little shock if I touch the pots and my strings.

TL074 pins

1-3.5

2-3.5

3-3.5

4-7.7

5-3.4

6-3.5

7-3.5

8-3.3

9-3.5

10-3.5

11-0

12-3.5

13-3.4

12-1.4

lm13700n

1-1.2

2-0

3-3.5

4-3.5

5-4.7

6-0

7-4.7

8-3.5

9-3.5

10-4.5

11-7.1

12-4.7

13-3.5

14-3.5

15-0

16-1.2

78l05

in-7.1

g-0

out-4.9

Q1

D-1.7

g-4.3

s-3.7

Q2

E-.6

b-4.9

c-4.9

Q3

E-1.2

B-.6

C-4.9

[alanp]

I'm officially stumped, I built the swaw and it wont quack.. I get clean signal, but there a nice little shock if I touch the pots and my strings.

No clue, but something is seriously wrong if you're getting electric shocks.

[blearyeyes]

Try cleaning up the external wire connections on the PCB just in case somehow one is getting shorted to the ground plane.

When you're testing are you using a battery or Power Supply?

[blearyeyes]

your voltage regulator is only seeing 7 volts, if its from a battery maybe the battery is kaput?

looks like your trying to run this puppy at 7v.
it might not run at 7v?

[mgwhit]

Why are you jumpering between IC3 and TR1 on the back of the board?

[jimilee]

Why are you jumpering between IC3 and TR1 on the back of the board?

Error on the board, the notes on v3 point it out, it it's in the empty hole between tr1 and tr2 it grounds it.

[jimilee]

your voltage regulator is only seeing 7 volts, if its from a battery maybe the battery is kaput?

looks like your trying to run this puppy at 7v.
it might not run at 7v?

It's a regulated 9v power supply.

[gordo]

Got a working board if you want it.  You could trouble shoot from it and end up with two of them.

[mgwhit]

Error on the board, the notes on v3 point it out, it it's in the empty hole between tr1 and tr2 it grounds it.

Okay, thanks.  Just found that on the GPCB Forum.  It wasn't in the PDF I downloaded (or the schematic).

It's weird that you're getting 7.1V on your regulator and ICs.  Test your voltage either side of D4 and either side of R28.

Are you playing it boxed or attached to a test rig?  I built my original test rig with the Beavis Board-style voltage sag, and that control has bitten me on the butt more than once.

[jimilee]

Error on the board, the notes on v3 point it out, it it's in the empty hole between tr1 and tr2 it grounds it.

Okay, thanks.  Just found that on the GPCB Forum.  It wasn't in the PDF I downloaded (or the schematic).

It's weird that you're getting 7.1V on your regulator and ICs.  Test your voltage either side of D4 and either side of R28.

Are you playing it boxed or attached to a test rig?  I built my original test rig with the Beavis Board-style voltage sag, and that control has bitten me on the butt more than once.

I learned from building gpcb boards, BOMS and directions are subject to change without notice, you have the check the website.
http://www.guitarpcb.com/apps/forums/topics/show/8230458
Note: If you have an V3 board and not V3B then you will need to run a single jumper wire along the backside of the board. That's it.
Connect a jumper from the 5V output pad of the voltage regulator (IC3) to the extra center pad for the trim pot.
the IC3 pad is marked "O" for Output, top right pad as viewed from the top, top left as viewed from the back of the board.

Got a working board if you want it.  You could trouble shoot from it and end up with two of them.

That'd be cool. I'm pretty sure at this point though, I just need to reflow, Those eyelets are so small.

[jimilee]

Error on the board, the notes on v3 point it out, it it's in the empty hole between tr1 and tr2 it grounds it.

Okay, thanks.  Just found that on the GPCB Forum.  It wasn't in the PDF I downloaded (or the schematic).

It's weird that you're getting 7.1V on your regulator and ICs.  Test your voltage either side of D4 and either side of R28.

Are you playing it boxed or attached to a test rig?  I built my original test rig with the Beavis Board-style voltage sag, and that control has bitten me on the butt more than once.

I have it on my testing rig with a regulated power supply. Forgive meif I get this wrong,
(+) Anode-9.5 (-) cathode 8.4 R28 since it's parallel to the diode we'll do it the same way. (+) 7.5 (-) 8.8

[jimilee]

So for those of you keeping score, reflowing everything fixed it!

[blearyeyes]

Cool Jimi, glad you got it working!

[jimilee]

Cool Jimi, glad you got it working!

Thanks. It was a stupid rookie mistake. Those eyelets are so tiny on that board, and I've been doing this for a while, and well...

[blearyeyes]

Yea well I just went through a week of frustration after putting 2 LEDs in backwards.. It happens to us all...


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