need help degugging a distortion+ pedal

[drk]

im following the debugging topic, so the numbers here correspond to that topic

1.What does it do, not do, and sound like?
In bypass, it works normally, when i press the switch, it lights up the led, but no sound or noise.. nothing.

2.Name of the circuit = The Plus - Distortion kit

3.Source of the circuit (URL of schematic or project) = http://www.musikding.de/product_info.php?cPath=52_122&products_id=617&osCsid=95ffb19ee352f1d932d81fe353e14de8

4.Any modifications to the circuit? No

5.Any parts substitutions? No

6.Positive ground to negative ground conversion? No

7.
What is the out of circuit battery voltage? = 9.01volts

Voltage at the circuit board end of the red battery lead = 9volts
Voltage at the circuit board end of the black battery lead = 0volts

IC1
P1-0
P2-9
P3-8.39
P4-0
P5-0
P6-4.21
P7-3
P8-0

PS: i dont know the order of the pins, so the order i used is according to this foto. dont really know if its this way we count or not
(i counted the upper left is 1, then 2nd upper left 2... upper right is 5.. you got the idea - http://s166.photobucket.com/albums/u99/noobiePT/?action=view&current=30-10-07_2307.jpg )

D1
A- 0
K- 0

D2
A- 0
K- 0

D3
A- 0
K- 0

other image, it isnt very clear but could help
http://s166.photobucket.com/albums/u99/noobiePT/?action=view&current=03-11-07_1447.jpg
thanks all

[petemoore]

  I'm not sure I can cypher the OA pin assignments.
  Starting by looking down at the top of the chip, there's a dot' in the top left corner indicating pin 1.
  so.. 
        1 * u    8
        2          7
        3          6
Gnd. 4           5
  Most of the D+ Schematics and layouts are for a single opamp assignment, to use a dual OA would require a different layout and pin assignments, see data sheets for single and duals to compare...
  The '*' indicates where the dot on the top of the OA would be when it's oriented as above, also the 'u'...many/most opamps also have a 'divet' in the center of the top between pins 1 and 8.
  IC1
P1-0
P2-9
P3-8.39
P4-0
P5-0
P6-4.21
P7-3
P8-0
  These numbers are strange enough for recommending start with the applicable data sheet [first make certain whether the layout is for a single or dual opamp assignment], and inform, the musikdog link isn't working for me.

[drk]

  I'm not sure I can cypher the OA pin assignments.
  Starting by looking down at the top of the chip, there's a dot' in the top left corner indicating pin 1.
  so.. 
        1 * u    8
        2          7
        3          6
Gnd. 4           5
  Most of the D+ Schematics and layouts are for a single opamp assignment, to use a dual OA would require a different layout and pin assignments, see data sheets for single and duals to compare...
  The '*' indicates where the dot on the top of the OA would be when it's oriented as above, also the 'u'...many/most opamps also have a 'divet' in the center of the top between pins 1 and 8.
  IC1
P1-0
P2-9
P3-8.39
P4-0
P5-0
P6-4.21
P7-3
P8-0
  These numbers are strange enough for recommending start with the applicable data sheet [first make certain whether the layout is for a single or dual opamp assignment], and inform, the musikdog link isn't working for me.

hey, thanks for explaining the numbering. i think its a single opamp(as it only got one lol).
what you mean by "start with the applicable data sheet"?

[axg20202]

If it's a clone of the Distortion plus, its a very simple circuit (basically a simple opamp booster circuit with diode clipping) - not much to go wrong. I would suggest checking over your circuit to make sure you haven't made a basic error in placing the components on the board e.g. are the electro caps mounted the right way round in terms of polarity? Get yourself a magnifying glass and make sure you haven't got any solder bridges between the traces. Is the IC seated properly in the socket? Also, double check your switch wiring and all your wiring to the board. You may have done this already, but do it again.

Lastly, in the photo it looks as though the board is just sitting on the bottom of your metal enclosure - I'm stating the obvious here, but are you sure that you aren't shorting out the circuit because the underside of the board is touching the casing?

[drk]

If it's a clone of the Distortion plus, its a very simple circuit (basically a simple opamp booster circuit with diode clipping) - not much to go wrong. I would suggest checking over your circuit to make sure you haven't made a basic error in placing the components on the board e.g. are the electro caps mounted the right way round in terms of polarity? Get yourself a magnifying glass and make sure you haven't got any solder bridges between the traces. Is the IC seated properly in the socket? Also, double check your switch wiring and all your wiring to the board. You may have done this already, but do it again.

Lastly, in the photo it looks as though the board is just sitting on the bottom of your metal enclosure - I'm stating the obvious here, but are you sure that you aren't shorting out the circuit because the underside of the board is touching the casing?

the circuit is very simple, thats why im not understanding why it doesnt work, i've checked the wiring alot of times, and the polarity too, and its the right way, but i didnt check for solder bridges.
when you say that the ic is seated properly, you just have to attached it into the the socket, you dont have to do anything else right?

as for the photo, i still didnt fixed the board, but when i test i make sure it isnt touching anything.
thanks, gonna give it another look

[drk]

hey, i tryed just now using the audio probe, and what i figured out is that i got sound until a certain point, and then no sound at all, from what i understand, when it goes to the negative part of the circuit it has no sound... dont know if what im saying is right lol... but in some resistors/caps, in one side i had sound but the other side no sound...
help me out!

[petemoore]

  Here's one ... I typed 'LM741 data sheet' in the search bar and got:
  http://www.national.com/mpf/LM/LM741.html
  The rectangle shows the pinout looking from the top, legs down, this is a signle OA, you can see that some of the pins are N/C, these would be assigned as _/+ inputs and an output on a dual OA.
  Notice the V+ as pin 7, it should be the same as your layout.

[PerroGrande]

Okay -- let's look at this circuit...

The IC is a good ol' LM741 single op-amp.  In this circuit, operating off a single supply voltage, you should have 9V at pin 7 (V+) and 0 at pin 4 (gnd).

With no input, you should have around 4.5 volts on Pin 3 of the IC.  (Vref at 1/2 V+)

Things to check based on this information:

1) IC Orientation.  Make sure pin 1 is in the correct place.
2) Solder bridges, wiring errors, etc.

Make sure the IC is firmly seated in the socket.  You should be able to turn the board upside down and shake it without the chip moving at all.  If it pops out, it wasn't seated properly.

Once you get the basic voltages sorted out, we can proceed to other troubleshooting as necessary. 

[oskar]

IC1
P1-0
P2-9
P3-8.39
P4-0
P5-0
P6-4.21
P7-3
P8-0

Check R6 to ground... I think you have an open connection there.

oskar

[hellwood]

see if the pin you are calling 3 is connected to your power supply. if so the IC is in 180 off.

[drk]

hey, its working 
the problem was that i cutted to much of the wire of the resistences, so the solder didnt touched some of them. i solded everything again and now works
thanks all for the help
btw, really nice effect, great distortion