Problem with BOSS CE2 by Tonepad Switch Wiring

Started by ricbox, May 13, 2012, 05:36:05 PM

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ricbox

Hi everyone! I'm probing a Corrral Chorus (this one:http://tonepad.com/getFile.asp?id=101) and unfortunately, the signal doesn't even pass through the input. Am I wiring the switch right? I've added a LED, and it even lights up when it's bypassed. Wicked!





Thanks in advance.

Seljer


ricbox

Thanks! It worked. But now the effect doesn't start: voltages seems ok, there's power though the circuit, but no effect on the signal.

ricbox

Little update! Voltages are fine, expect for IC3, the MN3007: i get 8,5V on pin 7 and 8, the ones connected to R14. How can I resolve it?

Govmnt_Lacky

Quote from: ricbox on May 14, 2012, 11:26:07 AM
Little update! Voltages are fine, expect for IC3, the MN3007: i get 8,5V on pin 7 and 8, the ones connected to R14. How can I resolve it?

1) What are you comparing your voltages to?
2) Pin 7 and 8 of the 3007 appear to be connected to V+ (9VDC) throught R14. Seems to me that you should see these voltage readings on those particular pins. I could be wrong though  :-\
A Veteran is someone who, at one point in his or her life, wrote a blank check made payable to The United States of America
for an amount of 'up to and including my life.'

ricbox

Quote from: Govmnt_Lacky on May 14, 2012, 12:16:31 PM

1) What are you comparing your voltages to?
2) Pin 7 and 8 of the 3007 appear to be connected to V+ (9VDC) throught R14. Seems to me that you should see these voltage readings on those particular pins. I could be wrong though  :-\
1) Always compared to Ground.
2) Yes sir, you're right. But i took as an example this picture I found somewhere, with the correct voltages.

Govmnt_Lacky

#6
I would start with these:

1) Check your resistor values. Look over the entire board and check the color bands to ensure there are no wrong values.
2) Check for solder bridges. Especially around the runs leading to Pins 7 and 8 of IC3.

I got my money on #2  ;)

Good Luck  ;D

EDIT: Do any of the other voltages on IC4, Q4, or Q5 have the identical readings? That might lead you to a solder bridge  ;)
A Veteran is someone who, at one point in his or her life, wrote a blank check made payable to The United States of America
for an amount of 'up to and including my life.'

ricbox

Quote from: Govmnt_Lacky on May 14, 2012, 12:42:50 PM
I would start with these:

1) Check your resistor values. Look over the entire board and check the color bands to ensure there are no wrong values.
2) Check for solder bridges. Especially around the runs leading to Pins 7 and 8 of IC3.

I got my money on #2  ;)

Good Luck  ;D

EDIT: Do any of the other voltages on IC4, Q4, or Q5 have the identical readings? That might lead you to a solder bridge  ;)
Nothing. seriously, All voltages seems fine on ICs and Qs. But I cannot probe it right: there's too much lead and the probe doesn't work on it. Is there a faster way to probe it?

Govmnt_Lacky

I can only assume that you mean you are having a hard time checking for solder bridges because of the lead runs.

You can always check from the component side. Just make sure there are no DIRECT shorts where there shouldn't be.
A Veteran is someone who, at one point in his or her life, wrote a blank check made payable to The United States of America
for an amount of 'up to and including my life.'

ricbox

#9
Quote from: Govmnt_Lacky on May 14, 2012, 08:51:55 PM
I can only assume that you mean you are having a hard time checking for solder bridges because of the lead runs.

You can always check from the component side. Just make sure there are no DIRECT shorts where there shouldn't be.

Ok, I've measured the voltages.
I've setted the trimpot to reach 6,2V on IC1 pins.
But...

there's definitely  something weird going on around IC4 and IC3 pins 8 and 4.
On tonepad they suggested to lift pin4 of MN3007: no success.

Govmnt_Lacky

Something does not look right with your V+.

IC1 has 9V on Pin 8... BUT... IC2 only has 7.9V on Pin 8  ???

You should not be dropping over 1 volt between the power rail from IC1 and IC2.

Double check your caps, diodes, zeners, and resistors connected to the power rail again.
A Veteran is someone who, at one point in his or her life, wrote a blank check made payable to The United States of America
for an amount of 'up to and including my life.'

ricbox

Quote from: Govmnt_Lacky on May 15, 2012, 07:11:38 AM
Something does not look right with your V+.

IC1 has 9V on Pin 8... BUT... IC2 only has 7.9V on Pin 8  ???

You should not be dropping over 1 volt between the power rail from IC1 and IC2.

Double check your caps, diodes, zeners, and resistors connected to the power rail again.
The fact is that I use a battery, I haven't installed a DC power jack, and I even haven't got a power unit to supply constant +9V. During testing the battery probably ran out. I'll check again, thanks for sparing your time!

ricbox

Does 82K (yes, underscored) on a capacitor stand for 0,0082uF? Because that could be the problem.

Govmnt_Lacky

Quote from: ricbox on May 15, 2012, 08:58:24 AM
Does 82K (yes, underscored) on a capacitor stand for 0,0082uF? Because that could be the problem.

Pretty sure the "K" is a tolerance rating.

What kind of cap is it and where are you using it?
A Veteran is someone who, at one point in his or her life, wrote a blank check made payable to The United States of America
for an amount of 'up to and including my life.'

ricbox

Quote from: Govmnt_Lacky on May 15, 2012, 09:06:42 AM
Quote from: ricbox on May 15, 2012, 08:58:24 AM
Does 82K (yes, underscored) on a capacitor stand for 0,0082uF? Because that could be the problem.

Pretty sure the "K" is a tolerance rating.

What kind of cap is it and where are you using it?
It's a ceramic capacitor. I've got 2 on the board, one is C12 (placed after Q3 emitter) and the other one is C7 (placed after Q2 emitter).

Govmnt_Lacky

Standard labeling for that capacitor would be 822K. Crossing this number comes up with 0.0082uF +/-10% tolerance.

Where did you order that cap from? Do you have a part number? You may be able to sub in a 0.01uF cap just to check. Its close enough to see if that is the problem.
A Veteran is someone who, at one point in his or her life, wrote a blank check made payable to The United States of America
for an amount of 'up to and including my life.'

ricbox

Quote from: Govmnt_Lacky on May 15, 2012, 10:15:44 AM
Standard labeling for that capacitor would be 822K. Crossing this number comes up with 0.0082uF +/-10% tolerance.

Where did you order that cap from? Do you have a part number? You may be able to sub in a 0.01uF cap just to check. Its close enough to see if that is the problem.
It hasn't any part number.
Actually I bought them from an electronic store near house, LOL. They sometimes sold me uncorrect material, but I never check capacitors before soldering. Guess I should give it a try with a 10nF ceramic then. I just hope not break the copper due to intensive resoldering.

Uh, and I've substituted IC1 with a TL072CN, it has removed the clicking. You know what, the sound is kinda compressed, I can head a volume boost, but just a little subdued effect. 

ricbox

Nope! Nothing changes. Damn, I really don't know what to do.

Govmnt_Lacky

Other than trying the fix from the Tonepad discussion boards (lifting Pin 8 of the 3101)...

You may be the victim of a DOA MN3007  :-\
A Veteran is someone who, at one point in his or her life, wrote a blank check made payable to The United States of America
for an amount of 'up to and including my life.'

ricbox

Quote from: Govmnt_Lacky on May 15, 2012, 11:41:44 AM
Other than trying the fix from the Tonepad discussion boards (lifting Pin 8 of the 3101)...

You may be the victim of a DOA MN3007  :-\
Some mixed details:
- Changed the battery.
- Diode Zener 11V gives me 8,9V, probably because it's connected to the power trace.
- Checked all transistors, they all have HFE between 350 and 380. Some different Volt values, however.
- Already lifted pin8, didn't change. Sound comes clean, if not slightly boosted.
- There's continuity everywhere, no dead tracks.
- Pots sign a total value of 63,7 kohm each one (I think it's a multimeter mistake), but I can't hear any change in the sound: just the increasing ticking of the Rate pot.
- I always buy twice the component I need: it would be inappropiate for Musikding to sell me a couple of dead MN3007.