Hi. I'm planning to restore a Concert PA head that I've been associated with since it was new in 1970. We used it as a main PA until things got really loud, and it was relegated to a monitor system. Eventually it couldn't even cut that. It's been in my barn for about 25 years and needs new Integrated Circuits in the preamp/mixer section (the circuit board on the back of the front panel). I don't have a schematic, but the I.C.'s are (I think) Fairchild op-amps. The part number is 7739393/U6E6946. If anybody has any info on them, it would help get this unit back in working order. Thanks, Matt
