I own a generation 2 ('72-'76) Acoustic Control 150 head -- love their amps. I want to give it a general housecleaning (recap, check voltages, clean pots, etc.) but, (re inspired by Teemu's book!) I'm also considering some minor mods like inserting an fx loop, tweaks to the tone stack and small improvements to the power amp. Thanks to the folks at the Unofficial Acoustic Control site I have access to the owners and service manuals, with schematics and signal+dc parameters, for the pre-'72 150 head. Problem is, the newer ones (at least the 17-11 preamp board) were revised. The only info I've been able to scrounge off the 'net about the revision is: the rated power output went from 110rms to 125rms and the tremolo circuit dropped the optocoupler for a FET component. Suppose I could trace the pcb's and hack a schematic, but my eyes and head for the maths to calculate voltages and freq's are kinda shaky lately.

I feel pretty cheesy asking, but I really can't afford $20 just now to buy a scan of the service manual/schematic and wonder if anyone here could email (or provide a link to) a copy relating to this revision for me? (Hangs head, shuffles feet)

Thanks!
Rob