Octavia Clone Screeching Feedback Oscillating Issue

[kleydj13]

I just finished a GGG TOCT which is an old Tychobrahe Octavia clone.  I'm having some odd screeching which you can hear [here](https://www.youtube.com/watch?v=h5ThX52EaW4).  It gets worse as you increase the fuzz.  To my ear it sounds like the effect is working as it should, just with that horrid screeching layered on top.

I measured voltages as follows:

9.4vdc in

Q1 - An old PNP OC42 Germanium transistor from Smallbear
4.7
4.5
3.12

Q2 - A new 2N5088
9.4
3.12
2.5

Q3 - A new 2N5088
5.4
2.5
1.8

These seem to be in line with what the build docs suggested:



Pics of the board:





Some other bits that might be important:

The PCB is from GGG and I checked that I purchased it in 2010.  It has survived a number of moves and only just this past week did I decide to build it.  I noticed that the vias had a little bit of coloration possibly indicated corrosion or rust?  I noticed I was able to get good solder joints if I gave it a little extra time to bond.  But I also notice that the solder is not flowing through the via at all.  Meaning if I apply solder to the back, the front appears to have no solder.  I have already reflowed all my joints once, but I just have concern that the corrosion is creating weird microphonics causing the screeching?  Any good way to deal with this corrosion issue?

The Q1 PNP Germanium transistor is also quite old.  It is the only PNP I have right now not in circuit.  I have one of those $20 parts testers from Amazon, but I don't really know how to test if it is dead or leaky.  Can an old GE PNP Transistor be the cause of the screeching?  Mircophonic?  I have some 2N5087's on order, but they won't be here for a bit. 

I am currently testing the circuit out of enclosure using aligator clips.  I would expect some extra noise, but could an enclosure fix the screeching?

Any other thoughts on how to troubleshoot this issue?  Thanks.

[kleydj13]

As a followup I believe I resolved the issue.  I ordered some 2N5087 transistors and swapping that in for the old Germanium I had in Q1 seems to have stopped the screeching for the most part.  I have reflowed a lot of my joints.  The oxidation seems to make it harder to make a secure joint, but not impossible.

[antonis]

Soldering wires on top (items side) of PCB isn't considered good practice..
(leaving also whiskers uncut..)

[aelling]

There are some good tips and trick (with photos) on soldering in this thread on the byoc forum, I found it really helpful when I started soldering and building effects. http://www.byocelectronics.com/board/viewtopic.php?f=9&t=6401