Thank you so much. I'll see if I find one of their email adresses. That might bring up more than a mail to the general "public inquiry" mailbox of NASA.
Some people (mainly those with an interest in audio/Marantz) are extremely interested in information on that equipment. I hope to share some space knowledge with them in the process.
Edit: I believe I already found a photo showing the 9120 amplifier. You might not get the big deal, but compare it to finding photo's or information about a modified (improved) saturn5 (say, used for military purposes) that is very badly documented but would be the best launcher ever. The impact is about the same with this 9120 in some audio fanclubs. Edit2: there is so much equipment in those stations, it might very well be another piece of equipment. It has one round gauge in the center as does the Model9, but the gauge seems to be of a different kind, as used in a lot of other equipment in the station. Anyway, if I get the emailadress, I'll sent some pics of the Model9 along, and together with the function description he might understand which equipment I am talking about.
Hamish Lindsay is also one of the persons who dismantled the station after the Apollo era, so if the 9120 got thrown away, I know who to blame for destroying the pinacle of amplifier technology
.