Troubleshooting a brassmaster

[1wahfreak]

Hey guys,
I'm building a brass master for a friend of mine using RG's layout and a board from GGG. I get very little volume (amost none) but I can hear that it is distorting. While checking connections and solder joints, I ended up pulling Q2 out of the socket and low and behold I got a great signal albeit slightly gated. With Q2 out, the volume works well and so does the sensitivity but not the bass control.

Here are my transistor voltages

Supply - 9.62v

Q1
E - .23v
C - 2.23v
B - .87v

Q2
E - .37v
C - 1.0v
B - 1.0v

Q3
E - .43v
C - 8.80v
B - 1.0

Q4
E - 62mv
C - 4.44v
B - .67v

Q5
E - 3.8v
C - 5.0v
B - 4.44v

Q6
E - 0.0v
C - 9.21v
B - 1.41v

Q7
E - 1.94v
C - 9.49v
B - 1.32v

I've ran over it with a fine toothed comb but can see anything obvious. Any suggestions would be appreciated.

[1wahfreak]

Can anyone lend a hand??

[moosapotamus]

Most of the times that I've had those symptoms, the cause has been an improperly installed transistor. How many times have you double-checked pinouts and installation?

I never measured the voltages in mine, but the collectors on Q1 and Q2 look low to me. Kinda wierd that removing Q2 would be an improvement.

That's about all I've got. Maybe some other (more educated  ) folks could chime in.

~ Charlie

[R.G.]

It would help a huge amount if you posted links, not verbal directions to the schematic and layout that you used.

I know that seems trivial, but I have to go hunt down the ones I think you used before I can help.

Just offhand, something is very wrong. If you have read any of my troubleshooting stuff, you know that a silicon transistor must have its base emitter forward biased by about one silicon diode drop before it can operate as a linear amp. Several of yours are not, so that's an obvious reason it's not working right. The problem is how to tell why they're not.

Without looking any further, about 95% of all problems described like you describe this one have pinout problems, so that's always a fertile place to look.

The 'what to do when it doesn't work' article also asks about a link to transistor datasheets; did you look up your transistors' datasheets so you KNOW the pinouts?