brianroth

I am posting this (a bit long-winded.......) same info at several internet sites where MCI recorder owners (or new wannabies <g>) seem to visit.

Backstory. In 1984, I was on staff as Chief Engineer at a studio here in Okla. City, and we added two new MCI ("Sony badged" by that time) JH-110C stereo recorders. One was a 1/4" and the other a 1/2" machine. We also ordered two of the "full function" remote control units which provided transport and audio electronics control, remote control for the RTZ locator, etc. I personally unpacked and installed both of the new recorders.

Approx. 4 years ago, the original studio sold both machines to another local studio, which then sold the machines to the current owner. However, the two remotes/cabling stayed at the original studio with their promise "you can have those remotes when we unearth the cabling out of the floor troughs at some future time."

Maybe a year ago, I finally extracted the remote control cabling from beneath 25 years of OTHER accumulated cabling inside of the floor troughs during a complete "gut and rebuild" at the original studio, and I delivered the remotes/cables to the current owner of the recorders. Eventually, the current owner decided to string the remote cables from the 1/2" deck in his machine room and into the control room, and connect everything up.

KABOOM. I was called in, and could smell burnt parts, and found the AC mains 4 Amp fuse in the PSU was blown. The burnt parts were on the Phase Lock Loop (capstan servo) card...several TL081 opamps. I was totally stumped how those chips were burned, since the remote control box has little/nothing to do with the PLL board.

On another recent service call, I carefully checked the cables and connectors on both remote units for shorts, etc, and GINGERLY connected the remotes to the decks. Absolutely no problems, so I told the guys to re-string the cables. They did that today, and....

KABOOM. Studio owner was understandably irate with me, so I scurried back over there. Same story...blown 4A fuse, etc. They had disconnected the remote cables from the deck before I arrived, so I asked how the cables had been connected when it crapped out.

PUNCHLINE. The remote cabling has a 24-pin Cinch-Jones/Beau connector for the transport control functions, and that plugs into its own UNIQUE socket at the bottom of the transport. In addition, two cables extend from the remote control box and each terminates into a 10-pin Beau connector; those are to be plugged into the rear of the audio electronics drawers in the overbridge. See this snapshot showing the remote with the two 10-pin Beau connectors peeking out of the wire harness:

http://brianroth.com/library/mci-jh110c-remote.jpg

(One 10-pin Beau connector controls ready/safe/input/repro, etc. for tracks 1/2 while the second Beau is for tracks 3/4 if those audio channels are present.)

IN THEIR INFINITE WISDOM (?), MCI also used a 10-pin Beau socket down on the transport to provide some of the required interconnects to an external SMPTE/whatever sync unit. I had never paid much attention to the extra Beau connectors down on the transport since I never had to lock-up the decks.

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Plug the 10-pin Beau plug from the remote control unit into the 'SERVO' socket on the transport, and Bad Things happen!

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Silly me...I had always ASSumed that MCI used unique connectors for all "external" hookups, and in fact I had never noticed that "rattlesnake" after almost 30 years of being around those two decks. Shrug...I just knew the 10-pin Beau should be plugged into the audio electronics unit in the overbridge, and sadly, the current owner just HAPPENED to see a matching/wrong function 10-pin Beau socket down in the transport.

WHAT WAS MCI THINKING?HuhHuh Those connectors fall into the "hook it up into the rest of the studio" realm, and all SHOULD have been unique. Hmmmmm...I also wonder why MCI didn't just use an XLR-3 audio connector for the AC mains power inlet instead of an IEC AC mains power connector......JUST KIDDING!!!

rattlesnakes.....

Siiiigh..after 40 years working with Pro Studio gear, I still find myself saying "WTF was (so and so) thinking when they designed this???" Not just MCI...but plenty of other Guilty Parties as well.

Best,

(long winded) Bri

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Brian Roth Technical Services
Oklahoma City, OK
www.BrianRoth.com