Need a little advice for (two) NEC PC-VCR model: PV-S98A VCRs

[jwillis84]

I came by a couple of VCR's that initially weren't working.

Both model: PV-S98A made by NEC labeled PC-VCRs

They have two rubber belts on the loading tray, and one toothed belt on the main drive.

One powered up but wouldn't load or play a tape.

Second wouldn't power up.

I think they stopped making them about 1990.

The first I found the perfect sized loader tray belts, and it now loads and plays a tape.

The first seems to have phenomenal tracking, and must have some sort of TBC because the picture is rock solid.. it looks like film. The hi-fi audio is unlike any I have heard from any other VCR the floor is quiet and sound is bright and crystal clear. However the picture has a low contrast washed out appearance.. like most VCR's get when the capacitors go. I can't find a service manual for it anywhere. All I have is the programmers / users guide.

The second it turned out the linear power supply had a blown fuse, one of those glass cartridge types. It has like six glass fuses spaced all around its huge power transformer. I swapped the good fuse from same position in the the working vcr for test and it powered right up.. very bright display. When I loaded a tape however it seemed to spool properly and wrap around the drum, but in drive mode it started screeching.. that lasted maybe half a second and the arms retracted and unloaded then ejected the tape.

I know they are super old.. but they are so close to operating.. I just don't know how to proceed.

I'm not in a hurry.. but I'd like to repair them, or get them serviced.

I guess I'm looking for good advice.

[dellsam34]

I would not keep them if they are not S-VHS with S-Video out, Maybe they can be used as tape rewinders or sorting through tapes.

[jwillis84]

Actually they are S-VHS, and Hi-Fi.. they both have an RS-232 port on the back.

The manual says they are capable of sub 3 frame positioning for playback or editing using some pre-SMTPE time code which the manual says it can lay down on the linear audio track.

I get a sense they were something special back in the day, long before Digital Editing was a glimmer in the eye of LucasFilm.

The "Linear" power supplies alone are something I've never seen in a consumer device.. they are always cheap switching power supplies.. with the usual noise those produce.

But they are also definitely not broadcast quality machines.. I think they cost a ton of cash to make that long ago.. NEC probably lost a lot of money on this model and bailed from the VHS market soon after.

I'm taking the long view with these machines and just.. listening to what other people suggest.

I'm in no hurry and I don't want to destroy them, or toss them in a landfill.

The screeching one makes me think its some sort of mechanical problem.

The washed out one.. I'm not sure how to proceed.

[dellsam34]

If you can fully restore them I'm pretty sure some members here or at digitalfaq are looking for such equipment, You can either donate them or sell them, that is up to you. Maybe keep one for some odd ball tapes.

[lordsmurf]

Those look like modified AG-1960.
I highly, highly doubt NEC made a VCR. But adding a PC board to a Panasonic is likely.

We need photos.

[lingyi]

NEC made Beta VCRs, which as I recall were self-manufactured. I remember considering getting one during my Beta VCR craze days. I believe they were only available in Japan.

Here's some info about the OP's VCRs. A strange and interesting beast. http://vintageapplemanual.biz/rare_vtg_nec_pc_vcr_personal_computer_control_system_pv_...e_recorder.htm

Edit: Here's some info about the NEC Betas. Learned something new, they made a SuperBeta machine!

I learned about a lot of Japan only equipment because I used to buy Japanese electronics magazines and just look at the ads! BTW, I don't read or understand Japanese.

[jwillis84]

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This is probably the worst looking one of the two, its a little beat up.

Not a single surface mount component on any of the circuit boards.

The medium blow fuses I ordered for it arrived today, and I replaced the blown one.

It seems to work, except for just after it wraps the tape around the drum and starts to play.

There is a loud squeal for about half a second, the arms retract and it spools the tape back into the cartridge and ejects it.

The tape does move when its on the drum.. its like a load sensor or something detects high tension and halts operation.

I don't know what triggers that.. perhaps the tape isn't moving fast enough?

Or maybe a brake is dragging on the supply spool turn style (I don't know what you'd call it).

My gut feeling is its in need of minor mechanical maintenance.

I don't see anything that looks broken or bent.

Its built like a tank.. and not only that transformer weighs a ton.. so does the whole chassis.

[dellsam34]

This is not unique to NEC, JVC and Sony made VCR's with CompuLink I believe, where you can control editing functions from the computer.
The good VCR's are the ones made in the mid 90's where the technology of video processing was at the top, Anything earlier is too old, anything later is too cheap.

[lordsmurf]

Some of my JVCs have CompuLink. Never used it.

That NEC is very Panasonic-looking. I'd bet on it being a rebadge. Either AG-1960, or something close.

Post on this in the digitalFAQ repair forums.

[orsetto]

NEC did once offer both Beta and VHS VCRs. The Betas came first, then as that format began tanking dramatically in North America NEC quickly added VHS. They did make an effort to have styling cues and operational quirks completely match between formats. I owned both NEC formats at different times in the '80s. The Betas were OK, certainly better than Sanyo, but not as good as Toshiba or Sony. Visually and operationally more elegant than any other Betas I ever owned, but the PQ wasn't quite there and they broke down often. The NEC VHS were very very good: among my favorite VCR models (and I have owned countless VCRs over forty years). Among the last of the VHS VCRs with a price point that allowed solid build quality and a noticeable effort at worthwhile differentiation. Unfortunately NEC VHS arrived too close to the tail end of that period, within a couple years even premium VHS HiFi became a commodity at fire sale prices. NEC could not hope to compete with the likes of JVC and Panasonic with giveaway 4-head HiFi models, so bowed out of the picture in early 1991.

These models were all decidedly of NEC mfr, or at least custom bespoke OEM jobs. I vaguely remember coming across some famous audio brand one-off VHS HiFi model that was suspiciously similar to my NEC, so possibly NEC managed to cull one or two relabel deals there. The Betas were unique to them, and didn't stay long on the USA market.

Anyway... this PC-VCR is a new one on me, never heard of it. The cabinet design cues are a combination of classic NEC and '90s-era Panasonic PAL AG series. The buttons, switches and sliders are pure Panasonic, as is the tape transport: LordSmurf is almost certainly correct that this was a Panasonic rebadged for NEC, perhaps with a contract proviso that NEC would get to claim the RS-232C feature as an exclusive novelty for a couple of years. Just prior to or simultaneous with the PV-S98A, NEC offered a twin "consumer" DS-8500 version with a more typical all-black cabinet, minus the PC connection but adding a jog/shuttle dial on the front right panel. Oddly, the consumer DS-8500 is rather rare compared to the rather obscure PV-S98A, which some weeks you'll find a couple listings for on eBay.

The most mysterious aspect here is Panasonic's involvement. This specific chassis and feature combo does not slot neatly into Panasonic AG series history: the thing looks like the unplanned result of AG-1960 and AG-1970 having a drunken sleepover together. Like the 1960, it has no TBC, and the same display window. The front panel input jacks are located in precisely the same position as the AG-1960. But the NEC lacks some of the finer picture adjustments, and the drop down control door is laid out much closer to the 1970/1980 (yet isn't exactly like those either). The display is blue instead of the typical orange, with the audio level bar meters to the right of the counter instead of the left, and the transport/PSU doesn't quite match any Panasonic AG I've opened (tho again, unmistakably Panasonic: the position of the loading motor and design of the head drum preamp is very close to AG1970). Panasonic would never have committed to mfr a single bespoke new model just for NEC to sell a couple hundred copies of: this had to have been based off an existing Matsushita industrial AV design. Since it does not quite match any of its North American AG cousins, my best guess is the NEC PV-S98/DS-8500 were based on one of the more prolific EU PAL-centric NV or AG models.

Interestingly, Panasonic must have thought NEC's "PC VCR" concept worth pursuing after the NEC VCRs disappeared. The RS-232C PC control feature resurfaced in the mid-1990s AG-5710, which was a reworking of the infamous AG-1980. Unlike NEC, however, the AG-5710 did not attempt to reinvent the edit control track paradigm. The 5710 simply allowed control of the VCR via industry-standard console and edit controller protocols, the control track remained the same consumer format as always. JVC took advantage of this lapse in the 5710 to release their SR-S365U, which combined RS-232C compatibility with standard post-production time code signal record/playback (re-purposing the linear audio area, as NEC had done). Ironically, despite its near $2K cost, the 365 is one of the least desirable VCRs JVC ever made (atrocious tracking, no TBC or DNR, eats tapes like crazy).

(The fairly common "CompuLink" feature isn't the same as the RS-232C feature of the NEC, AG-5710 and JVC 365. CompuLink was a consumer protocol that did not necessarily interface seamlessly if the VCR was plugged into a standard post suite, RS-232C was more compatible with U-matic and C edit desks and EDL systems.)

[orsetto]

After researching a couple old video newsgroups from the prehistoric web, it seems the NEC PV-S98A and its twin DS-8500 were introduced on the cusp of NEC's departure from the consumer electronics business, circa late 1990- early 1991. NEC folded its VCR tent completely by 1992, so this model was not long on the market. Given the date, we can narrow down what Panasonic chassis the PV-S98A was based on: I think it would have to be whatever the PAL equivalent was to the US/Canada AG1960 or 1970. In those days the PAL AG and NV models diverged somewhat from their similar NTSC counterparts, often with completely different transport mechanisms that were never seen in the NTSC market. This would have been around the time the 1960 was replaced by the 1970, so perhaps the PV-S98A was a transitional prototype that never went mainstream. The button panel layout and blue display do not correspond with any North American AG or the usual EU NV-FS88, 90, 100 or 200.

If the transport design is anything like other comparable Panasonic AG series, your problems with squealing and tape loading are traceable to worn brake wheels and/or split nylon coupler attaching the worm gear to the loading motor shaft. Possibly compounded by a dirty or failed mode switch. All are a real PITA to service, but can be sussed out for DIY if you can identify exactly which transport mechanism this is so you can refer to the correct Panasonic AG service manual. Removing the transport and disassembling to get to the parts is a nerve-wracking drag (I just did it this week), but the manuals do make the procedure fairly clear.

Certain transport repairs are more amenable to DIY than others: depending on the issues and their severity, the proper repair may require calibration tapes and alignment tools not readily available to most DIY enthusiasts. Sometimes its easier to just swap the entire mechanism out for a known-good donor: the transport mechanics, head drum and preamp come out as a single modular unit (albeit not easily). If you can identify exactly which mechanism this is, it should be fairly easy to find a compatible donor VCR.

The pastel colors are probably caused by the usual capacitor aging problems typical of Panasonic AG VCRs.

[jwillis84]

Thank you for all the research Orsetto. And for the historical perspective.

I've been practicing setting things aside for a while to think.. to avoid obsessing over things. The two PC-VCRs are still in their same shape.

1992 is a long time ago.. but I can remember it quite well.

The brake wheels, or a mode switch problem sound like good possibilities.. it might even be a bad main drive belt.. I haven't looked on the squealer.

The Pastel colors being bad capacitors sounds about right.

I'll check back in an let people know how it goes.

As a matter of fact I found an AG-5710 a few years ago in a North Texas AV studio which seemed to have been mostly ignored and in good shape. I promptly shipped it off to Tom Grant for a tune up and any necessary cap repairs.

I also picked up an AG-1970 from some place.. I think it was from a retiree who hardly ever used it.

I'm completely embarrassed by the number of VCRs I've picked up without much thought.

Now I'm constantly thinking about getting rid of them.

But I'm still fascinated by them.. and DVD recorders.. and capture cards.. and USB capture devices.

I need to get a different hobby.

[orsetto]

I need to get a different hobby.

Nah, you just need to get a bigger house!

Agree: setting things aside, sometimes for a long while, occasionally yields unexpected positive results. I've been sitting on a pile of half-dead, useless Panasonic AG1980s and AG5710s for longer than I can remember. After a recent unplanned binge of random VCR purchases, a couple of which were very high end late-model broadcast SVHS, I was a bit surprised to discover my sole fully-operational AG1980 not only held its own but bettered all of them in a couple of respects when playing a subgroup of tapes plagued with an obscure cable box signal defect.

While the broadcast decks trounced the 1980 and edged out my JVC SVHS and MGA DVHS in terms of naturalistic detail and color purity, they vomited all over this one obscure defect, which unfortunately affects hundreds of my lower-priority tapes. This led to a week of comparison tests with all my VCRs, dvd recorders and capture devices., the net conclusion being the AG1980 is the best compromise of video performance vs defect suppression for these specific problem tapes. The majority of other tapes unencumbered by this defect vary widely on different make/model VCRs (as usual in such large projects), with JVC SVHS, Mitsubishi DVHS or the broadcast decks taking the lead depending on the recording.

Anyway, these recent discoveries motivated me to try and resurrect at least one more functional AG1980 or AG5710 from my pile of zombies. At various points in the past I made feeble unsuccessful attempts at DIY repair, but these models are daunting to access mechanically and the electronics are a hopeless nightmare best left to a professional. This time around, I realized I had nothing to lose (having invested less than $90 in each "corpse" years ago). The junkers would either be DIY fixed by parts swapping, or I'd finally sell them off as parts units to get them out of my hair. The two service manuals (one for overall VCR, one for the transport) got me 80% there but I got really stuck halfway thru removing the transport. Consulting a few youTube repair vids about similar PAL Panasonics got me over the hump.

A decade after setting them aside as hopeless junkers, I've now managed to cobble together two additional fully operational AG1980s from my pile of six dead hulks. My three AG5710 remain unsalvageable with DIY, alas: too many parts diverge from the 1980, disallowing mix-n-match swaps. While the TBC/DNR, PSU and transport are the same, the control panel, display, and video boards are not interchangeable between 1980 and 5710. The point of my story being, if a VCR seems too difficult to repair, or you lack the confidence or documentation to dig into them, setting aside for a few months (or years in my case) might allow one to clear those hurdles.

Although I will say, the AG1980 / 5710 definitely confirmed their reputation as a disassembly horror show. Apparently all the AG/NV models with flip-down control panels employ a similar, nasty internal arrangement of insanely nested parts and cables: NOTHING comes out or goes back in easily or quickly. The transport is a brilliant, single-piece unit that at first glance looks like it should simply lift straight out of the chassis. Nope: for no good engineering reason, you literally have to tear the entire VCR apart before you can lift out the transport intact (front door, front panel, bottom cover, entire electronic harness). Utterly ridiculous design, extending to the boards and connectors as well, which defeats the whole point of everything being modular. My fingertips are still bleeding from the demented, infernal plug locks Panasonic employed on umpteen bunched-wire connectors that must be detached. The only element of the AG1980 that fully complies with the modular concept is the PSU, which lifts right out after removing three screws and unclipping one (infernal) multipin connector.