There's a lot of equipment like that out there.
Basically, you're talking about a midi or SMPTE syncronizer. Fostex makes synchronizing equipment, time code generators, etc. There's a mfr called JLCooper, that makes this type of gear. Depending on what you want to sync together, adapter cables might be an issue, and you might have to make cables, DIY-style.
I can't be very specific, and can't quote exact model #'s, etc. Although I actually own all this gear, I never have used it. I haven't 'graduated' to that level yet. It's very high techy, and I haven't studied up on it.
-I have a Fostex 4030 sync box, and an 8700 time code generator, plus I have some MTC-box by JLCooper.
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All these synchronizers work basically the same way, don't they?
-Lots of units lend themselves to plug & play synchronization, like the Tascam TSR/MSR series recorders, and practically every Fostex R/R recorder from
the Model 80, onward.
-There are also several Tascam synchronizer systems out there, sorry, I can't quote model numbers.
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You may have to watch Ebay more, to find out exactly what synchronizer units that are out there.