GGG Ibanez BP10 Compressor troubleshooting

[spialv]

Hi everyone! I'm newbiew in stompbox bulding. For the start I choose to make Ibanez BP10 Compressor. I made PCB and buy components on my own. After fixing all of the missing jumpers problem, my pedal still doesn't work (it just generate some strange tone). I was trying to fix it by checking pin voltages given in the http://www.generalguitargadgets.com/pdf/ggg_ibp10_instruct.pdf  and found some intresting moment - In the PDF they say base voltage of Q1 should be 0.6V. But checking the schematics (http://www.generalguitargadgets.com/pdf/ggg_ibp10_sc_mod.pdf)  base of Q1 is supplied by 9V through voltage divider of R2= 9k1 and R3= 22k resistors which equals = 9V*22k/31.1k = 6.36V wich I get before R4 of 511k. But in the point of connection of R4 and Q1 base the voltage is 3.93V (If I get it right Base current is about 5microAmps) I have checked Q1 by testing p-n pairs and it semms okay. So my question is  - why do I get so strange voltage values and how exactly this circuit should work. Thank you in advance!

[duck_arse]

hello spialv, welcome to the forum.

you are exactly correct and have found a documentation error. the Q1 voltages should read very similar to the Q11 voltages [allowing for slight Vbias variation ....] as they are both "unity gain" voltage followers, or emitter followers. perhaps you could advise ggg.

first question - where did you get your BA6110 from? second question - what are your measured voltages on each transistor and the IC pins? third question - why haven't you posted up some photos of what you have built, so that we might check your work?

[spialv]

duck_arse, thank you for your replie. I didn't attach the photo, because it's a bit messy and I was not sure it will be informative. I will attach it here. In process of checking voltages I found damaged capacitor C3. I think the problem is that emitter of Q1 have higer voltage than Pin1 of IC1 (marked orange in the list). If we suppose that Q1 works fine and voltage on ICs pin is correct - its obvious that C3 in scheme fragment is connected with wrong polarity.  Wich sounds pretty wierd, so I think the problem in the first emitter follower, but it looks so simple or I'm so unexperienced that can't find out what the problem is.  I get my BA6110 on Aliexpress (not sure if it's allowed to post external links here). I'm also not sure if it's good quality, but seems that it's not the main problem of my device in this particular moment.

[PRR]

Emitter of Q1 should sit near 2/3rd of supply, NOT "zero". That is a typo.

Base of Q1 sits 0.6V higher than emitter, BUT your meter loads the 511k resistor so it reads lower when you are poking it. This is probably fine.

Agree that C4 appears reverse-biased. 1.1V reverse is not an emergency.

I suspect the chip is fake/reject. Get a good chip, then re-check voltages on C4, and get the polarity right.