At the Onsala Space Observatory, we had a LINC8 too. I operated it in ~1975/1976
as it was in used for processing data from the 25M telescope on 4 GHz.
I recognized the upside-down R561. Remember loading the tapes and also
the procedure to manually starting the boot-loader. Bottom left beside
all the data switches, there was a knob "Chime". Turning it on, the processing
could be "heard". If the system hang, the character of the sound would change.
The LINC 8 was salvaged from being scrapped and is on display at
the observatory today.
Ulf Kylenfall SM6GXV
SR Research Engr (Retired)
ex Onsala Space Observatory