I stumbled onto this very informative thread this morning while looking for info concerning a Toa RX-7-328 which I have. I originally purchased this board approx. 20 years ago (in about 1989) when the board was possibly 4 or 5 years old. I used it for about 5 years doing concert sound, and then installed it in a club in the 90's. It's been in storage since that club closed down approx. 12 years ago. I've decided to do "something" with it (as my New Year's resolution is to deal with piles)... haven't decided what to do with the board yet other than find it a new home... it's arguably too nice of a board to scrap out. I have decided I'll attempt to fix that which is wrong and is fixable before I work on finding it a new home. I remember there were issues with "pops" which I fixed by changing out "black boxes" on the modules... which I understand are "line amps". As I recall, when I put it in storage, there were channels starting to "pop" again. I have somewhere around 10 - 20 spare modules for the board, and I even have what I understand is a factory "test bench board"... which consists of a 2 module sized power supply, a few meters, and slots for about 8 total modules... so I have quite a bit to work with. My repair tech skills (and knowledge) are pretty rusty... so I'm wondering if somnium7 is still around as I'd love to ask some questions... specifically about those pesky line amps... and re-working of the power supply.
