need a little help with hells gain

[whomeno]

Hello everyone,
just built  hells gain on vero board. built 2 other pedals with no problems at all.
built from this site :http://tagboardeffects.blogspot.com/2016/10/handmades-hells-gain-hg-1.html
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works fine in bypass, but no go when turned on
uswing 9 volt battery

tlo74
pin 1 .99

2.071

3 0

4 1.70

5  .02

6  .55

7  .70

8  .80

9   .42

10  .82

11  .43

12  0

13  .56

14  .55


tlo72
1  .80
2  .33
3  0
4  .40
5  0
6  .96
7  .90
8  1.70

used max1044
1  1.70
2  0
3  0
4  0
5  .42
6  0
7  0
8  0

checked for shorts solder joints still no go this is the frist time useing a tlo74.
I probed and got signal to pin 5 of the 74. nothing out

[whomeno]

Pics

[Marcos - Munky]

Well, you should have about 9V on pins 1 and 8 of the 7660. If this IC isn't powered correctly, the rest of the circuit won't be powered too. Also, the pins 8 and 1 must have the same voltages; This is where you should start the troubleshooting.

I didn't checked your board. It's just that veroboard layouts just doesn't make any sense to my head.

[whomeno]

pins 1 and 8 now have 8 volt  pin 8 of 72 has 8 volt

[Slowpoke101]

You have a 47K resistor next to D5. It is supposed to be a 47R (yellow. violet, black).
May be part of the problem.

[whomeno]

yes I caught that one changed it got power where i should
been probing got sound out of the 74 now still now sound at 7660s and 72

[Slowpoke101]

The 7660 is not part of the audio circuit. It is meant to generate a negative voltage (split rail) on pin 5. However the 072 should have audio.
Install this missing resistor;



Test again and check all the voltages again. Please let us know your results.

[Slowpoke101]

Also I found one missing cut;

[whomeno]

I did find missed cut . added missed 100k
tlo72
1  0
2  0
3  0
4  0
5  0
6  0
7  0
8  7.69
Also i have no audio on treble - lows and volume pots

[Slowpoke101]

OK, progress is good.

You should have -8Volts on pin 4 of the TL072. This is supplied from pin 5 of the 7660 (or similar). You should also have -8Volts on pin 11 of the TL074. The missing voltage is probably caused by a problem with the 7660.

Check the area around the 7660 for shorts, missing links, etc. Check the voltages on the 7660 and let us know your results.

[whomeno]

072 pin 4 -5.70
7660 pin 5 -5.70
074 pin 11 -5.70
7660
1  7.03
2  3.42
3  0
4  -2.79
5  -5.47
6  2.11
7  2.88
8  6.93

[Slowpoke101]

OK. It appears that the 7660 is working but the voltage on pins 1 and 8 is a bit low. Make sure that your battery is supplying 9 Volts or close to it.
Looking closely at the component side of your board some of the resistor values are hard to see but I do think that you do have a few incorrect values installed. Double check your 2K7 and 27K resistors. Also check the 4K7 and 47K resistors. Check them and correct any errors then measure all the voltages on the ICs.
Also check the voltages appearing at either end of the 47R resistor. Let us know your results please. I think that you are very close to success.

[whomeno]

ok I now have audio coming out of 072 pin 7 going to 1uf cap but not going through cap to output.
any suggestions

[whomeno]

ok all resistors are right.
voltage at jack 8.90
074
1  .04
2  0
3  0
4  6.11
5  0
6  0
7  0
8  .94


9  .11
10  .08
11  -4.80
12  0
13  0
14  0

7660
1 5.82
2  2.85
3  3
4  -2.38
5  -4.68
6  1.85
7  1.95
8  5.70

072
1  0
2  0
3  0
4  -4.70
5  0
6  0
7  0
8  5.66

47r  5.60 both ends

[Slowpoke101]

The primary battery voltage still seems low but relative to it all the other voltages seem OK.
Your 1uF output capacitor is actually a 0.1uF capacitor. Replace it with the correct value and try again.
If you only have an electrolytic capacitor install it so that the positive lead of the capacitor connects to pin 7 of the TL072.

[whomeno]

same thing audio on pos side of cap nothing coming through
i used a 1uf  50v pos side to pin 7

[Slowpoke101]

Measure the resistance across the 2M2 resistor next to the 1uF capacitor. You may have a short circuit across it. Possible causes would be a stray wire or a wiring error.

[whomeno]

with meter on 20m coming up 0

[Slowpoke101]

Set the meter to a lower resistance range. Short the meter's leads together. The meter should show 0 or close to it. Then remeasure the 2M2 resistor. If it still shows 0 or close to it there is a short somewhere.
A picture of your wiring may help diagnose what's going on.

[whomeno]

still 0 the top of 2m2 gose to out put the bottom gose to volume 1
I don't see any stray wire or anything