Green Russian Debug Help

[greenpatch]

So I've recently built a pair of V.7 Green Russians from this vero layout (http://www.fredric.co.uk/misc/green%20russian%20big%20muff%20stripboard%20veroboard%20layout.gif)
using bc549c's, however there's a real volume drop in one compared to the other.

the first 3 trannies are fine,
However I've isolated the problem to Q4, which voltages across Base(1.6v) and Emitter(0.98v) are about half of what they should be according to this page (http://www.generalguitargadgets.com/pdf/ggg_bmp_instruct.pdf?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a)

Q4 Collector reads the correct voltage...

I've triple checked all solder joints and the components- replacing most of which surround Q4 to no avail and no change. Can anyone advise me as to where to look or what could be attributing to this problem...I going nuts here

Lemmie know,

Patch

[knurra]

Change transistor?

[runmikeyrun]

^ this.  

Sometimes stuff comes bogus from the factory.  It's rare but does happen.  

Double check that your transistor is in the correct way.  Seems stupid, but happens to the best of us.  

If that doesn't fix it, use a magnifying glass in good, strong light and do a careful inspection of the solder side of the board.  Sometimes hairline solder connections can occur that are very hard to spot with the naked eye, but jump right out under the 'glass.  Do the same with your trace cuts.  With vero it's really easy to have near-invisible solder bridges between traces or a trace cut that's not quite complete.  

Anyone working with vero should have a magnifying glass.  I also have an exacto knife that I run the length of the board in between the copper strips to make sure there's no solder bridges.

Oh... and welcome to the forum! 

[greenpatch]

Yep and yep, tried all that and checked the affecting resistors of Q4 manually to check for faulty units. Nothing. I enlarged all the cuts and ran all the vero lengths with a knife, cleaned it all up with a dremel. Changed Q4 twice and no bladdy joy.

Any other words of wisdom out there besides binning the thing?


- and thanks for the forum welcome.

[PRR]

> Q4, voltages across Base(1.6v) and Emitter(0.98v)
> Q4 Collector reads the correct voltage...

Re-check what parts are at R21 R22 R23 R24.

It seem impossible that E (R23) is wrong and C (R24) is right if the values are correct. (Same current flows in both.)

Check for DC voltage on R25. Should be zero. If not, C13 is shorted or leaky.