Newbie NPN Fuzz Face bias problem (solved!)

[picohogshead]

Hello! As my first attempt at pedal DIY I've implemented this schematic on stripboard.


This is the actual circuit as re-traced from the finished rat's nest: (strips running vertically, no cuts or links)



The sound is gating very badly, barely audible at its loudest (also there's a deafening ground loop but I should be able to deal with that). I'm powering the circuit from a 9DC wallwart. The voltage in each strip (numbered from the left) is as follows:

1: 0
2: 9.77 (+9v from the PSU)
3: 0.53
4: 0.30 (Q2c)
5: 0.94 (Q1c, Q2b)
6: 0.30 (Q2e)
7: 0.29 (Q1b)
8: 0.21
9: 0 (from PSU ground, Q1e)
10: 0.11

From reading various Fuzz Face troubleshooting threads here it looks like Q1 might be within the bounds of ok, but at 0.30 Q2c is completely wrong. Can you see based on this data what could be causing it?

[Dasher]

Yes, the Q2 collector voltage looks low. Any chance you can post a picture showing the top and bottom of your veroboard? You may have a solder bridge somewhere.

Also, according to your hand drawn layout, the tip of your input jack is grounded and the ring is going to the 2.2uf input cap. This should be reversed.

[duck_arse]

hello picohoshead, welcome to the forum.

please, can you post some photos of what you have built? also, what transistors are you really using? are they BC183L (which might match your layout) or BC183A (which, from the datasheet, would be wired wrong - depending on your manufacturer ....).

http://pdf.datasheetcatalog.com/datasheet/fairchildsemiconductor/BC183.pdf
http://pdf.datasheetcatalog.com/datasheet/motorola/BC182B.pdf
http://pdf.datasheetcatalog.com/datasheet/MicroElectronics/mXuvyzv.pdf

[late poster, slow reader.]

[edit : also, I may have mis-interpreted your layout drawing, maybe those transistors are right ....]

[Ben Lyman]

Just a WAG here, but since track 2 has v+ and tracks 3&4 are so low, my first suspect is the 330r. Is it a 330k by mistake?

[picohogshead]

Orange, orange, black, .....ORANGE. Now it's just got a bad connection somewhere, plus the grounding issue, and it's done. Thank you, and thanks for the input everyone!

(The BC183A's I was sold are apparently two different makes. One has an "SH" monogram and the other says something like ΠY.)