Reverse engineering a phono pre, help these old eyes

[dano12]

I've spent the last two days reverse-engineering a low-cost commercial phono pre. I've been as diligent as I can in getting it right, but after many hours my eyes are going crossed. Anyone have some free bandwidth to see if I'm on the right track?

Here's the schematic I have so far, does it look remotely like a discrete phono pre? I can't figure out why there is no DC supply to the collector of Q1...

An externally hosted image should be here but it was not working when we last tested it.

Doh, I guess it would be helpful for me to include the photo of the PCB with the parts legend. Here's the link because it is a rather large file:

http://www.beavishifi.com/ComPhono_PCB.png

 

[alayn91]

Hello,

According to the PCB picture, you have forgotten R12, 270KR, from Vdc+ to Collector of Q1 and base of Q2.

Regards.
Alain.

 

[dano12]

Hello,

According to the PCB picture, you have forgotten R12, 270KR, from Vdc+ to Collector of Q1 and base of Q2.

Regards.
Alain.

Thanks very much for the good catch. I've updated the schematic--it is looking more like a valid circuit now.