Rullywow Queen of Bone debugging (volume too low)

[astaleb]

Hi All,

I just completed a Rullywow Queen of Bone pedal and it's not working correctly.  I have the circuit boxed and it functions correctly except that is it very under-powered.  I have to set the volume & gain at noon just to get the pedal to achieve unity gain (it doesn't seem to matter what dip switch settings).  Also, because the signal seems to be much weaker than it should be, the amount of noise the pedal generates is ridiculous.  Short story - it's a weak, noisy pedal that sounds like crap.  Any suggestions from the group would be welcome

Here's what I've done so far:
- Inspected, reflowed all solder connections & improved lead dress where necessary
- Checked all components for the correct value
- Checked electrolytics, diodes, IC's for orientation
- Checked IC & Diode voltages as follows with input of 9.11V

MAX1044 (the right kind with the audio spec)
1: 9.15
2: 4.65
3: 0.0
4: -4.41
5: -4.26
6:4.43
7: 6.90
8: 9.15

JRC4558
1: 8.71
2: 8.71
3: 7.92
4: 0.0
5: 8.68
6: 8.72
7: 8.68
8: 17.58

JRC4558
1: 8.71
2: 8.72
3: 7.96
4: 0.0
5: 8.68
6: 9.52
7: 8.71
8: 17.58

Diodes (left side)
1S15888
8.68
8.68
MA858
8.69
8.20
8.71
8.20

Diodes (right side)
1S1588
8.69
8.68
MA858
9.42
8.55
8.69
8.65

[patrick398]

Hey, welcome to the forum!
Are you sure the voltages you posted for the MAX1044 are correct? The voltages at the 4558's look OK and you're getting 17v at pin 8 of those ICs but your 1044 isn't putting out 17v according to your list

[astaleb]

Hi Patrick,

Thanks for the warm welcome. I measured it twice with my Fluke MM so it's gotta be accurate. I also swapped another 1044 chip in to see if the chip may have been damaged and I get the same readings.

But, that is a HUGE help. I'll pull the board and have a close inspection to the socket soldering.

Cheers!

[garcho]

Are you sure the voltages you posted for the MAX1044 are correct? The voltages at the 4558's look OK and you're getting 17v at pin 8 of those ICs but your 1044 isn't putting out 17v according to your list

Voltage doublers don't put out the higher voltage until after the cap and the diodes, the 1N5817, center right in the pic.

[astaleb]

Great info - I'll take a measurement there when I get a chance.

[highwater]

I have a MAX1044 on my breadboard right now, and my voltages match yours (after accounting for my rather lower battery voltage), so that shouldn't be the issue. Your opamp voltages look correct as-well.