Rescuing a big ol' U-matic video deck

I was briefly into video stuff around the 1989-1990 timeframe, running around events with an 8mm handycam being "creepy camera guy" and using a motley assortment of old hardware to do some primitive editing on. I wound up with intermediate copies of stuff on several different formats -- 8mm, VHS, U-matic, and even Beta for a while. U-matic was sort of the mid-level "studio standard" of the day, although already being superseded by Hi-8 and SVHS, and the digital revolution was a not-so-distant rumble in the distance but most people were still editing on tape and trying to strategize their copying to minimize generation loss through the chain.

Even though the gargantuan old U-matic deck I owned back then was already archaic at the time, it could deliver fairly clear content so I had used it to assemble up random clips of this and that. It wasn't an editing deck and didn't even have a proper pause control, but by sticking a small screwdriver down into the right place in the transport and quickly wedging the pinch-roller arm off the capstan I could usually get a crisp enough pause for my, uh, "work". Looking back on it that was hilarious, but real editing decks of that caliber were out of reach for most not-all-that-serious hobbyists. I could live with a few frames of rainbow squigglies here and there, but it really brought home what a manic-depressive sort of activity video editing can be. Especially on that old iron.

Fast-forward to today, and computers had finally gotten fast enough to do fairly good video capture into mildly compressed but high-quality files. Time to convert some of that old stuff to digital format for supposedly easier archival! There was one particular "wedding video from Hell" that I wanted to recover and distribute, as it represented the pinnacle of my so-called editing ability and would be a nice retrospective of our social community from back then. I couldn't even remember which format I had mastered that one on, as I think I'd given that to the, uh, "clients". While most of my source material was on a small stack of 8mm tapes, I wanted to see what I had on U-matic that might still be useful [and if I could start getting rid of some of those oversize cassettes, that couldn't hurt either]. But my ancient deck had long since headed for the electronics-recycle, and I needed to borrow another one long enough to dump out what I had.

The local tech community delivered, in the form of a still-working Sony VO-5850 editing deck, with flying erase and a jog knob and everything. Well, said to be working, but it couldn't hurt to inspect the innards first as these things generally want a good cleaning after sitting in someone's storage before being trusted for optimal playback.

[Thumbnail images link to larger copies.]

Guts of a U-matic deck Four screws and the top was off, revealing the massive transport inside. They *do not* build stuff like this anymore. 50+ pounds of Real Metal, no foolin' around! An absolutely rigid tape-path chassis. That monster head drum, with very visible [and serviceable!] slip rings under a protective dust cover to carry head signals in and out. And this does what's called a U-load, carrying a loop of tape all the way around the drum instead of just pushing up to either side of it, which is a fairly impressive brute-force choreography of mechanical parts by itself.

However, the insides were *very* crapped up. The normally bright shiny drum surface looked all misty, there was clearly old oxide crud on some of the linear heads and rollers, and bits of corrosion here and there. And the grease on the loading gear train had clearly dried up and hardened. Good thing I checked in here before even attempting to power the thing on. At least the one rubber belt I could see here looked to be in okay shape.

Filthy pinch-roller The worst part was the main pinch-roller, covered in some kind of soft white almost-powdery goop which the folks on the mailing list suggested might be mold. This ultimately had to come completely out to get properly cleaned, but with alcohol and some light buffing I did manage to recover it back to a fairly good rubber surface. I still don't know what that white crap really was, but it and the isopropyl-wipe it rode out on are now out of my life.

Roller cleaned, partially loaded It took a careful hour-plus to clean everything to the point that I'd trust giving it a tape to load, and I picked the most expendable one in the collection to gingerly try. Things happen very fast once you shove one in; the carriage drops down with an authoritative ka-chunk and the front tape cover gets flipped up and a set of rollers that ends up inside the cassette immediately pulls a little vee of tape partially out past the drum like we see here. Even when the unit is in full stop; the tape is never fully put away until the cartridge is ejected.

With some bit of trepidation I pressed "play" and watched things closely. The ring took the rest of the journey around the drum and more solenoids went "clack" and then ... it was playing, and not tearing my tape into mylar confetti! Yow! And the picture was solid, if a little on the soft side -- but what should I expect from tapes made in 1976. This is all the low-coercivity brown stuff, nothing magnetically robust about it.

Bottom open, lower board and takeup drive The loading ring needed an occasional helpful nudge to get going around on tape insertion, and I also discovered that fast-forward and rewind were just too weak to overcome the friction of the takeups and that small vee of external tape path. Someone suggested opening the bottom to clean that part of the transport so I did, shown in all its nicely serviceable glory here, but cleaning the belt and pulleys for that didn't really improve things. That part probably needed a newer, tighter belt which I wasn't about to go find a replacement for. I also couldn't easily access where the shuttle roller bore against either spindle without major further disassembly, so there may have been more to that problem.
The workaround was to let the tape fully load into playing and "search" mode and then use the jog knob cranked way over to run forward and back, which while passing the tape through everything used the capstan to help it along and overcome the rest of all the transport friction. Whatever, for a few one-off playbacks I could wait.

This side also shows the tilted precision motors for the drum and capstan, each one heavily flywheeled but still fully speed-controllable to let all of the seek and editing functions work.

Capture setup, running Elgato widget Finally I could sit down and do my captures. One nice thing this deck has is a signal-strength meter from the video heads right above the tracking knob, to help center on the peak output. I could watch that for any degradation which would hint that it was time to delicately clean the little video heads again. As I worked through the collection I had to do fairly frequent touch-up cleanings, as the old tapes did tend to shed oxide as they ran.

But run they did, and here's the simple setup with a piece of that same wedding-video component running. It's going as SD composite through an Elgato video capture widget hidden behind everything, a small bump-in-the-wire with video inputs on one end and USB on the other, straightforward to use and compatible with older Macs. It doesn't seem to consume a whole lot of CPU to produce 640x480 MPEG4-encoded files which are fairly high quality *because* they're not highly compressed. Using their applications's direct H.264 mode chews a lot more CPU, as one might imagine.

Far more hilarious than weddings of yore was what I found on some spare tapes I must have trashpicked somewhere: a batch of employee orientation and training videos from Holiday Inn, dated 1976. Here is a sample [27 Mb], which has such an amusing presentation of their "sophisticated computer network" of the day that I just had to preserve it. With all the factual errors and illogic that only a marketing department could come up with! The rest was pretty tedious but gives the general idea.

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