Yes,I have seen and worked on 16" transcription TT's.these were common in radio stations at that time.This was in the era before tape "cart" mnachines.Spots,announcements,etc were recorded on the discs.Have also seen the disc recorders-often called "recording lathes"At the place I work at they used to use them in the Wash DC studio plant.I have some transcriptions-found them during renovations.also have a few blank discs somewhere.--"Audiodiscs"Usually came in a box of ten-in various grades and two main sizes-16" and 12".They were aluminum discs with a black laquer coating that you recorded on.Neunman and Scully made the recording machines.It took some skill to use the recorder-there was a tonearm on the machine for test playbacks and a microscope so you could examine the groove you just cut for imperfections.The lathe was also connected to a vacuum system to remove the "chip" as the disc was cut.Sadly I came in to work when they just stopped using the disc machines and got rid of them.I wanted to use them.would have been fun.Its still being done today but on a smaller scale.endless loop cart machines replaced the Discs,and now--Digital recording playback and programming management programs for PC's have replaced the cart machines.You can still get parts for Gates TT's from Harris --They are the largest supplier of broadcast equipment.usually the idler wheels on these need cleaning or replacement.On your unit-leave its speed selector lever in a "neutral" position-in between the speeds-to avoid flats on the idler tires-had to remind DJ's about that all of the time-If you do have flat spots on the idler-set the TT to 78RPM speed and let it run for severla minutes-most of the time this will correct the flat spots.Also there are speed adjust screws for each speed-use a small screwdriver and a strobe dics and light for setting TT speed.A flourescent lamp makes a good strobe.Adjusted many of these in a studio using the flourescent lights as TT strobe lights. Good luck with your Gates TT.