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  1. I have pulled out my AG-7750 from years ago to archive old VHS tapes using the Canopus advc110. At first, the picture looked really good, but I had no audio coming out of the xlrs on the AG-7750. I then set the audio to normal instead of hi fi and for some reason all of my old vhs tapes are now playing back at something like triple speed. I do have audio now, but cannot get them to play a normal speed anymore. If anyone know this deck and supply any info, it would be greatly appreciated.

    Thanks!

    Howard
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    If the tapes are VHS and not SVHS (which is dependent on the original recording method), home movies, consumer theatrical films, and if the tapes weren't originally recorded in SP on a professional deck like the AG-7750 then more then likely you will have issues especially for tapes recorded in EP/SLP.

    Read this sticky, and also research around this site many threads also speak on why professional SVHS decks are not an ideal choice.

    https://forum.videohelp.com/threads/286055-VCR-buying-guide-(S-VHS-D-VHS-Professional)
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  3. The AG-7750 had an assortment of special playback modes. Be sure none of the rather cryptic "search" buttons is engaged or lit up on the front panel: this can result in smooth looking fast forward playback (and would explain why the sound only works from the mono track and at triple speed).

    I doubt that is your problem, though: more likely, your tapes are EP/SLP aka "6-hour" recordings, which I believe the AG-7750 cannot play at correct speed since it runs at SP/2-hour mode only. Loading an EP/SLP tape could result in triple-fast playback with no hifi sound, only speeded-up mono. Its been awhile since I used a 7750: it might be capable of EP playback but your unit may have a fault in the speed detection so it fails to set the correct speed based on the tape signal.

    As OldMedia notes, a 7750 wouldn't be the best deck for playing consumer tapes in any case, because the video heads are sized and optimized for professional studio use: these heads pick up and play out more noise than video signal when you load the typical consumer tape. The Faroudja noise reduction system helps a little but it still isn't an ideal match of VCR and tapes. These huge honking pro-line studio VCRs were never intended to get into the hands of consumers: aside from the $4000 pricetag, they aren't designed with consumer-spec tape playback in mind. (Its been long forgotten that consumer VHS and pro-studio VHS video track specifications diverged back in the mid-1980s: pro recordings play fine on consumer VCRs but consumer recordings often play rather poorly on pro VCRs).
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    If the video and audio is moving really fast, you are most likely dealing with a tape recorded in LP or SLP/ELP mode, and Professional/Industrial equipment can't play it back because they can't track it. You can however get a Panasonic AG1970 or 1980, and they will be able to play back LP or SLP tapes without issue.
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    Since this is an old thread, I'll post my issue here. I have the 7750 deck set up in an edit suite to do some audio dubbing onto VHS tapes on the linear tracks. The 7750 will be the recorder deck in the setup. I put in a tape into the deck with video already recorded on the tape. It picked up the video track as the video tracking was very good with the meter quite high. So it seems to be picking up the signal off the tape. Problem is the picture isn't being sent to the tv. I get nothing but scrambled black screen with colors flashing. When I turn off the TBC, it goes to blue screen. The time counter is working as it should, so its picking up the signal off the tape. I tried moving some switches on the deck like edit to play, etc. Nothing changes the scrambled video. I don't have a video signal being fed into the deck from the source deck (since I wont be recording video). Could this be a video sync problem? Im wondering if maybe its trying to sync up with a source deck for the picture to even play the tape? I would assume you could use the deck for playback without it being hooked up to anything, but this doesn't seem to be the case. Or is my deck in need of servicing?
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    In this slow time of COVID19, I haved turned back toward digitizing my archive.

    Sadly, my first two decks are in need of service:
    an AG7650 which sounds like it needs some lubrication and seems to have a TBC problem (red & blue checkerboard anyone?),
    an AG7750, which appears to have a tape stuck in it and when turned on sounds like it is trying to thread a tape then after a few unsuccessful tries, sulks and displays an "E-2" error message. It refuses to eject said tape.
    Is anyone out there aware of an engineer on the northeast coast of the USA who still services analog equipment? It has been so long since I sought such help that all my old resources have left the business, retired, closed down.
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    Well the TBC problem is a well known issue and unfortunately- unrepairable due to needing chip parts that are NLA. The threading issue mine did as well. I had to keep exercising the transport, but it could be more a mechanical issue with your deck. I used an old tech that has worked on these decks before, and out of 4 or 5 decks, I only got 2 usable. And I still have the same issues with mine. No one can repair these decks anymore due to lack of parts. Only thing you can do is search Ebay for another "working" deck and pray it does actually work.
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    Thank you
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    Seems like the only recent and active thread on this unit that sparks my interest. Why? Because it just looks awesome. There I said it. Instead of opening up a new thread and rehashing the same old story, I've decided to post here.

    Is it true that the 7750 has a defect where the TBC creates small vertical lines in the picture? Is there any way around this?
    Last edited by BenKlesc; 31st Mar 2021 at 05:07.
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  10. I sent my Panasonic to an ex-Panasonic engineer in Florida two weeks ago. He hasn't yet begun working, so I can't yet recommend him. Once I receive the unit back, probably next month some time, I'll post my opinion.
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  11. Crossing my fingers johnmeyer has great luck with the technician in Florida, and is able to recommend him. There were a few techs still "openly willing" to accept these behemoth pro decks for repair five years ago, but updated posts at DigitalFAQ suggest virtually all had exited the business by 2019-2020. What remains is a tiny handful of retired engineers who accept work on an extremely limited "pssst: Joe sent me" basis (you need to be referred by someone they like/trust, they aren't officially accepting repair business from the general public).

    Re the Panasonic AG7650 and 7750: like most other end-game late model big pro decks, they're a ticking time bomb of electronic woes. Nearly everything mfd circa late 1990s to early 2000s was plagued with defective electronics (counterfeit parts, badly engineered power supplies that slowly fry irreplaceable parts, poorly designed microprocessors that age out and die). Some of the final Panasonics (and similar JVC BR series) offered very advanced, complex, computerized internal TBC, DNR and Pro Amp features not seen in any other VHS decks. But these features employ bespoke, proprietary, low-volume chips that are difficult/impossible to repair/replace now. Age related failures are common, compounded by other ordinary parts failing and eroding things further downstream.

    The convoluted electronics in the later Panasonic 7000 series seem to have been fairly reliable up until 2013 or so, at which point a great many began suddenly failing. TBC and chroma issues are the typical complaints, repairs being either unobtainable or too expensive to risk (as the repairs don't always "stick" and can't be guaranteed). This is similar to the agonizing plight of Panasonic AG-1980 owners, only worse because there are no "go-to" 7650/7750 repair specialists universally recommended (like Deter or TGrant for the 1980). There aren't nearly as many surviving, in-use Panasonic 7000s as there are 1980s, which means nobody's really invested the time/effort/money to reverse engineer some of their thornier issues. Ditto other exotics like the JVC BR series or JVC WVHS decks.

    The only desirable late-model pro deck that seems to have eluded the "rotting electronics" syndrome is the Sony SVP-5600/SVO-5800 duo. Odd, considering all of Sony's other once-desirable consumer and pro-sumer SVHS models have long ago crumbled into landfill. Somehow they managed to source durable circuit parts for this pair of giant pro SVHS units. Possibly they have survived longer due to their less ambitious TBC/DNR/Proc Amp: these circuits are rock solid and high performance but have none of the digitally-controlled frills and fripperies of the Panasonic 7000 series or JVC BRs. Of course, you're still up a creek if you need mechanical repairs: parts for these giant Sonys are scarce, techs skilled in rebuilding them even scarcer.
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    I may buy one in a few months to archive my collection of 200+ VHS tapes from my camcorder days. Someone told me using pass-through devices it is possible to record the tape to digital with out really being able to see this artifact of lines. They also said this defect was fixed on the 1980 unit. it is only visible on the professional units. Not sure if that is a hardware defect that can be fixed or not, but have read about it in this forum many times.

    I must say they are mighty cool looking. If I should avoid them like the plague and I'm about to make a dumb purchase, please someone stop me right now. The thought of owning one may be too tempting to stop me though. From everything I read on them on the internet, it had the best TBC out there ever built. All of my tapes are SP so I have nothing to worry about in that regard.
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  13. Originally Posted by BenKlesc View Post
    Someone told me using pass-through devices it is possible to record the tape to digital with out really being able to see this artifact of lines. They also said this defect was fixed on the 1980 unit. it is only visible on the professional units. Not sure if that is a hardware defect that can be fixed or not, but have read about it in this forum many times.
    What "lines artifact" are you referring to? Can you link to a thread here that discusses it or a pic of what you mean? Because in general, "lines" in these discussions usually refers to obviously defective playback (clogged heads, electrical shorts in the chassis, mechanical issues) that can happen when any VCR breaks down.

    There is nothing special about the AG1980 beyond its exclusive TBC/DNR circuit, which many of us prize due to its optimized performance for many consumer-grade tapes (it strikes a unique balance of noise reduction and filtering vs adding fake artifacts due to noise reduction). Aside from that, it has better than average tracking of EP video and HiFi audio, but the same can be said for vastly cheaper and more reliable decks like the Mitsubishi HS-U748. What makes the 1980 peculiarly desirable and sought-after is the combination of excellent tracking with unique line TBC/DNR (similar to but different from the more common JVC DigiPure TBC/DNR).

    If by "lines" you mean the interlacing of pre-HDTV video, that is not something that can be eliminated by any VCR. You remove or "de-interlace" those lines using software after the digital capture to your PC. When you read forum remarks about the 1980 having "superior line TBC performance", they're referring to how the 1980 corrects geometric picture distortion like flagging, washboarding, wiggling, etc. Within the Panasonic VCR lineup, it was the best you could get by far, while JVC had many more models with similar (but not identical) line TBC performance. Each VCR is a compromise between line TBC performance, DNR performance, tracking performance, and reliability.

    I must say they are mighty cool looking. If I should avoid them like the plague and I'm about to make a dumb purchase, please someone stop me right now. The thought of owning one may be too tempting to stop me though. From everything I read on them on the internet, it had the best TBC out there ever built. All of my tapes are SP so I have nothing to worry about in that regard.
    The Panasonic 7000 series and similar JVC BR series had "interesting" TBCs with more features but are not necessarily "the best" performing TBC. Assuming a deck in mint operating condition, all these circa-2001 big pro VCRs had equally solid TBC performance in terms of stabilizing and conditioning the sync. Note this "frame TBC" replaces and eliminates the need for a separate frame TBC like DataVideo TBC1000, however it does NOT have the "line TBC" correction features of the AG1980 or JVC DigiPure VCRs. Line TBC is of more benefit to consumer/prosumer use, the big pro models like 7750 were never expected to handle consumer tapes with issues that would need a line TBC so they have only the more pro-oriented frame TBC. This confuses a lot of beginners when choosing equipment: line TBC is more akin to noise reduction, frame TBC was originally intended to maintain sync for analog dubbing, editing and video switching (as a byproduct this also patches MacroVision and corrects other instabilities that choke digital capture cards).

    The comments you see that the big pro Panasonic 7000 and JVC BR vcrs have "the best TBCs" refers more to their advanced, digitally-controlled "proc amp" features, which are multiplexed into the TBC controls to allow fine-tuning color and black levels and other image aspects more reliably and with finer control than the analog dial pots on more common designs like Sony SVO-5800. IOW, a perfectly-working 7750 has an excellent self-contained proc amp competitive with outboard boxes. While a technological marvel when they worked, most now don't work well at all, and getting them repaired is difficult/expensive (VERY expensive if you have to ship any distance or need donor circuit).

    If you just want one to light up and look cool on a rack, grab whatever example you can find at a good price with clean front panel. Otherwise, be prepared for a big dent in your wallet: 7750 in perfect working order from a reputable pro VCR specialist will be costly, 7750 from random eBay seller will almost surely require major $$$ overhaul (if you can even find a qualified tech willing to do the work). Given the average price of the much more common AG1980 overhaul now exceeds $600, assume that as the minimum expense to recondition the more complex, rare 7750.

    If your project mostly involves consumer camcorder tapes, you may be better off spending the money on a reconditioned AG1980 from Deter or TGrant. Tracking will be slightly better than with a 7750, while the line TBC and DNR of the 1980 may be more useful than the frame TBC/proc amp in the 7750. A bit of a toss-up, as the final cost is probably similar (the 7750 may require an additional line TBC passthru device, while the 1980 would need a separate frame TBC like DataVideo TBC1000 to match the built-in frame TBC of the 7750). Resale value when you're done could be another consideration: nobody is really clamoring for big pro SP-only decks like 7750, so you probably could not claw back anywhere near what you'd spend getting it overhauled. The AG1980 is a standard, well-known tool for VHS capture: good overhauled examples are much faster/easier to resell for a higher price.
    Last edited by orsetto; 31st Mar 2021 at 12:59.
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    Originally Posted by orsetto View Post
    If your project mostly involves consumer camcorder tapes, you may be better off spending the money on a reconditioned AG1980 from Deter or TGrant. Tracking will be slightly better than with a 7750, while the line TBC and DNR of the 1980 may be more useful than the frame TBC/proc amp in the 7750. A bit of a toss-up, as the final cost is probably similar (the 7750 may require an additional line TBC passthru device, while the 1980 would need a separate frame TBC like DataVideo TBC1000 to match the built-in frame TBC of the 7750). Resale value when you're done could be another consideration: nobody is really clamoring for big pro SP-only decks like 7750, so you probably could not claw back anywhere near what you'd spend getting it overhauled. The AG1980 is a standard, well-known tool for VHS capture: good overhauled examples are much faster/easier to resell for a higher price.
    Great advice. What I'm really looking for is a VCR that has SVHS line output. From what I read on the 7500 you can have it output SVHS even when the tape you are playing is not SVHS, and from reading around there are some apparent advantages? I'm also not sure what other models would have that feature.

    It's funny you mention Deter. I was just talking to him on here about the mysterious line defect and was interested if these can modified to eliminate this problem. Anyways I'm considering my options and probably won't make a purchase until the summer so I have some time to think it over.

    https://forum.videohelp.com/threads/364064-Restored-Panasonic-AG-1980-worth-the-price

    Originally Posted by Deter View Post
    vaporeon800, What do you want to know, as stated the TBC breaks the picture in to vertical lines, if you look close enough you can see them. At first I thought it was a problem with the machine DS-840 (I think that was the unit) Than tested out a few more of these decks and saw the same problem. Being old broadcast VCR's, when they made them, they were not being used on LCD screens, more like old school TV's. With my current LCD can see a heck of a lot more detail than when VCR's were really in use. My guess is they didn't know this was a problem cause they couldn't see it.
    Also to provide more info on my project. Most of the tapes I have are Polaroid Supercolor Plus T-120 recorded SP.
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  15. Originally Posted by BenKlesc View Post
    What I'm really looking for is a VCR that has SVHS line output. From what I read on the 7500 you can have it output SVHS even when the tape you are playing is not SVHS, and from reading around there are some apparent advantages? I'm also not sure what other models would have that feature.
    This one is an easy feature for you to get: *all* SVHS decks will play standard VHS tapes via their SVHS output connections. Some require you deliberately change a setting to do this, but most just automatically play all tapes thru all output connections simultaneously. Whether this will give you dramatically improved capture quality depends on the specific VCR example, tape example, and capture system. Generally speaking the SVHS connection will be technically better even with standard VHS playback, but technically better doesn't always look visually better to the human eye. Certain types of noisy recordings on standard VHS will have that noise exaggerated by SVHS connection, while the composite connection will conceal it somewhat better. "Expert" opinion flatly decrees "always use S-video connection no matter what on pain of humiliating death", but these edicts can and should be ignored if the result looks crappier than "technically inferior" methods. While it is usually good practice to follow conventional wisdom re capturing, feel free to use your own judgement to make changes if something doesn't look quite right.

    It's funny you mention Deter. I was just talking to him on here about the mysterious line defect and was interested if these can modified to eliminate this problem. Anyways I'm considering my options and probably won't make a purchase until the summer so I have some time to think it over.

    https://forum.videohelp.com/threads/364064-Restored-Panasonic-AG-1980-worth-the-price

    Originally Posted by Deter View Post
    vaporeon800, What do you want to know, as stated the TBC breaks the picture in to vertical lines, if you look close enough you can see them. At first I thought it was a problem with the machine DS-840 (I think that was the unit) Than tested out a few more of these decks and saw the same problem. Being old broadcast VCR's, when they made them, they were not being used on LCD screens, more like old school TV's. With my current LCD can see a heck of a lot more detail than when VCR's were really in use. My guess is they didn't know this was a problem cause they couldn't see it.
    Also to provide more info on my project. Most of the tapes I have are Polaroid Supercolor Plus T-120 recorded SP.
    Ah, the "vertical lines TBC issue": now I understand what you mean. This is strictly limited to SP-only broadcast VCRs with built-in frame TBC, primarily late-model Panasonics and a couple JVCs with their overly-ambitious digital proc amp tied into the TBC. This issue seldom occurs in consumer or prosumer VCRs with line TBC/DNR: the circuit function is significantly different. So you don't need to worry about it with the AG1980, various JVCs, or the Mitsubishi 2000 DVHS.

    Its is a rather obscure issue that largely flies under the radar: not that many people notice. Manifests with some of the big broadcast SP-only VCRs that had built in frame TBC. The TBC digitizes the analog VHS signal in order to smooth sync impurities and lock it to a stability standard, after which it is converted back to analog at the decks video outputs. During this analog>digital>analog process, some of these inbuilt TBCs divvy the video image up into a matrix of vertical slices. As Deter reports, this was concealed by the way CRT displays imaged video, but became visible on large modern HDTV LCD displays which themselves employ matrix processing.

    You don't hear much about this issue because quite honestly, no one is heavily using these ex-broadcast VCRs for capture work. A lot of us have dabbled with them, but they soon prove to be contradictions: one needs to grasp that bigger and more expensive doesn't necessarily mean higher performance at tasks for which they were not intended. Broadcast decks were intended to handle very high quality tapes made on broadcast camcorders, not consumer material. There is a tape quality floor below which these big decks actually perform worse than a consumer deck in several respects, and most consumer tapes fall below that threshold. Compounded by the fact most ex-broadcast VCRs you find today are in woeful need of an overhaul, disappointment ensues.

    My own experience with several showed them to be unpredictable and temperamental: with certain select tapes they can be extraordinary, easily outclassing a Panasonic 1980 or JVC DigiPure in picture clarity and HiFi audio. In particular, they're great with Hollywood tapes infested wth MacroVision. I keep a low-mileage Sony SVP-5600 for this very reason. But it happens way way less than you'd imagine: maybe 10% of tapes fall in their wheelhouse. More often, they'll display annoying artifacts in the picture that do not appear with any consumer or prosumer VCR, or have a tracking issue with the tape, or their lack of line TBC/DNR gives a result less satisfactory in toto than whats obtained from a 1980 or JVC DigiPure. There's a reason 95% of these discussions revolve around a handful of JVCs, the Mitsubishi 2000 DVHS, and AG1980: they have proved themselves with repeatable results over a wide range of common tapes. The big broadcast decks can be fun to play around with, and can give superb results if the tape/vcr combo is simpatico, but (usually) one quickly discovers their utility for capture is more limited than expected.

    Having said that, I'm just waiting now for johnmeyer to get his AG7750 back from the engineer he found to overhaul it, and tell us its the best VCR he ever used. General rules apply, until they don't. YMMV is a big factor here.
    Last edited by orsetto; 1st Apr 2021 at 12:27.
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    Originally Posted by orsetto View Post
    My own experience with several showed them to be unpredictable and temperamental: with certain select tapes they can be extraordinary, easily outclassing a Panasonic 1980 or JVC DigiPure in picture clarity and HiFi audio. In particular, they're great with Hollywood tapes infested wth MacroVision. I keep a low-mileage Sony SVP-5600 for this very reason.
    Interesting. So in your experience using your Sony, did your SVP-5600 suffer from vertical lines as well if you remember?

    What you suggest is very true that these machines are seldom talked about. There is a lot of lore and rumors about these machines being the "greatest" that were ever made, but that is all in relative terms from your excellent explanation.

    I do find the controls on those industrial machines to be very useful and interesting to have in front of you. Very much saves time post processing in software. I should clarify and say, the internal frame TBC on the AG-7500 probably outperforms any external frame TBC on the market. That's probably the only good thing I like about it. Include the 7500 frame TBC with it's controls and place it on the 1980 with it's smaller heads for consumer tapes and you would have the best of both worlds for archiving. You don't have to purchase an external TBC. I guess you could purchase an external line TBC and use it on those pro machines. Are there companies that even sell those around? An even better question/scenario, use the AG7500 as an external TBC from a second VCR feeding into it?

    From everything you describe, the 1980 has a more than capable TBC and perhaps line TBC that is better for consumer tapes. Correct if wrong though, the 1980 does not have built in frame TBC. It's all very fascinating because really, this forum is the only place that is talking about this format and keeping it alive.
    Last edited by BenKlesc; 2nd Apr 2021 at 09:27.
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  17. The Sony SVP-5600 player (and SVO-5800 editing recorder/player) do not suffer from any vertical lines issue that I've been able to see. Their internal frame TBC, while modern and very capable, is not as "digital-centric" as the TBC in the Panasonic 7000s. The big Sonys use the more traditional set of four rotary potentioneter controls on the front panel, accessed with a screwdriver, plus a couple of other menu-driven settings. The Panasonics over-reached a bit (a lot in retrospect) with the elaborate digital proc amp linked to the TBC in some of the 7000 models. This required more complex digital processing than simple frame TBC functionality, which led to the vertical matrix that can be visible on today's LCD panels.

    When dealing with VHS hardware, no matter how "pro" or recent, we always have to remember they're from the era of standard-def CRT displays in home and studio. Given the internal vcr digital tech available in the mid-'90s when the final pro SVHS generation was engineered, they employ some design tradeoffs that rely on the flexibility and fudge margins of CRT viewing. It was never expected the output would be viewed on a 32" or 65" LCD monitor optimized for HD signals, with its own digital matrix that harshly reveals every flaw in SD analog sources.

    The overall video processing circuitry of the big pro vcrs, esp the frame TBC if the deck has one built-in, is optimized for SVHS tapes recorded in these types of VCR themselves or in comparably pro-spec camcorders. Within this narrow optimized range, they can offer outstanding playback performance. But with wildly varying consumer tapes made in an endless array of VCRs or camcorder designs from who know what sources, they can falter. Noise creeps in that you wouldn't see with a prosumer AG1980 or JVC DigiPure. Horizontal bands of luminance disturbance, a form of ghosting, even some color instability can appear. Tracking range for HiFi audio can be less flexible than a 1980 or some other consumer decks. None of this is predictable: each tape is a diceroll, which is not something you want to deal with during capture when it can be minimized by using a 1980 or JVC DigiPure. If you're absolutely sure you'll exclusively be handling first gen camcorder material, a pro deck like 7750 might offer some advantages over a 1980, but for general purpose capture things could get mighty unpredictable.

    The TBC internal to some of the big pro decks is often cleaner-performing than what you can get from the usual external DataVideo TBC1000 used by many of us, but in most cases is self-contained within that VCR and cannot be used as a pass-thru TBC for other VCRs (expected to have their own internal TBC or patch thru an edit desk TBC en route). This reflects their studio-oriented design: production houses had their own dedicated systems for signal-syncing multiple VCRs. Special separate genlock and other taps on the back panel were used for this purpose (inapplicable to capture workflows).

    Re compatibility for capture use, the issues vary with the particular deck example and tapes involved. Very very few owners live anywhere near a tech who can overhaul one of these monsters to where they meet the specs and performance they had when new. Generally, the best you can hope for is a pro deck in reasonably good condition that operates without noticeable significant flaws. Such used-condition, unserviced decks will play some tapes extremely well, some decently well, and many with more mediocre performance than you'd expect. It isn't just the larger video head gaps: while it has an impact with many older tapes, it isn't a hugely significant element. Head wear and alignment is probably more important than gap discrepancies.

    This is before you even consider the typical "as found" condition and repair difficulties of the big pro decks. As has been mentioned by several owners both here and at threads on DigitalFAQ, the only reason to own something like the final Sony SVP/SVO 5000s, Panasonic 7000s, or JVC BRs is if you need a deck with their specs to match with a significant percentage of your tapes, and/or the TBC/proc amp features truly do have some special utility to you. But the sad fact is these once-$5000 vcrs were often made with unstable electronics and chock-a-block mechanical assemblies that were designed to be fine-tuned and parts-replaced by a technician every 1000 hours of use.

    Don't assume the instruction manuals and service manuals are being overly conservative when they suggest replacing the head drum and pinch roller every 500 to 1000 hours: they aren't kidding. While a big pro deck with 2000-4000 hours on the head drum will still work, the playback is often significantly impaired vs a serviced deck with newer heads. These behemoth VCRs are like pro Hasselblad cameras or British sports cars: depreciation has made them attainable for mortals to purchase, but the maintenance is still sky high expensive and/or unavailable. Proceed with eyes open.

    After experimenting with several big elaborate Pannies and JVC BRs, I swore off them until someone whose opinion I trust strongly recommended the Sonys as combining remarkably transparent frame TBC with rugged electronics. They're much harder to find in USA than Panasonic/JVC, as most of the Sonys seem to have been PAL format sold in Germany: I eventually snagged one in near-mint condition at a reasonable price. The frame TBC is indeed amazing, the color especially clean and pure, and the best HiFi/linear audio I've heard from any vcr. BUT... only a few of my tapes are 100% compatible with it to take full advantage of its performance. It does well with Hollywood movie tapes, and very clean first-gen camcorder material: thats all, really. Most other tapes pick up extraneous noise and other artifacts, similar to what I got from the big Pannies and JVCs. I'm keeping the Sony for those select tapes it handles flawlessly, but my go-to capture VCR is still a Panasonic AG1980. I can add an external frame TBC to the 1980, but adding the line TBC/DNR finesse of the 1980 or JVC DigiPure or Mitsu 2K externally to the large pro decks is difficult or impossible.

    At best, the difference between a big pro Panasonic/JVC/Sony vcr and more typical capture vcrs like JVC DigiPure/AG1980 is noticeable but not dramatic: each will have subtle advantages over the other No matter how good the TBC, all these vcrs entail a redundant analog>digital>analog>digital process when capturing. Based on examples I've seen, captures using the much less common Ensemble/AJA pro hardware workflow are capable of the most noticeable improvement. These systems omit the redundant analog>digital step: once digitized by the TBC, the signal remains digital thru the final capture format (instead of being converted back to analog at the VCR outputs, then re-digitized by the capture device). Such systems aren't discussed much in capture threads due to rarity and expense, but they've proved an excellent alternative for the few who can obtain / deploy them.
    Last edited by orsetto; 2nd Apr 2021 at 16:34.
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    Originally Posted by orsetto View Post
    At best, the difference between a big pro Panasonic/JVC/Sony vcr and more typical capture vcrs like JVC DigiPure/AG1980 is noticeable but not dramatic: each will have subtle advantages over the other No matter how good the TBC, all these vcrs entail a redundant analog>digital>analog>digital process when capturing. Based on examples I've seen, captures using the much less common Ensemble/AJA pro hardware workflow are capable of the most noticeable improvement. These systems omit the redundant analog>digital step: once digitized by the TBC, the signal remains digital thru the final capture format (instead of being converted back to analog at the VCR outputs, then re-digitized by the capture device). Such systems aren't discussed much in capture threads due to rarity and expense, but they've proved an excellent alternative for the few who can obtain / deploy them.
    First I want to say, thank you for taking the time to type all of that out. Very useful information!

    Second, when you mention Aja I assume those are capture devices with their own TBC that bypasses the internal TBC.

    I can say all of the tapes I'm looking to archive were my old VHS tapes from my old camcorder. First gen.
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  19. Originally Posted by BenKlesc View Post
    when you mention Aja I assume those are capture devices with their own TBC that bypasses the internal TBC.
    This I can't answer at the moment, as I have no hands-on experience with the setup. The one VH member I know currently using it contacts me sporadically to furnish samples but has been occupied with other projects the past couple months. Don't remember if he mentioned whether he kept the Sony 5800 internal TBC switched in or out. I would imagine out if an external was in the loop, but I'm not really familiar with the variables of these SDI capture chains. A few other active members have direct experience with this more exotic form of capture: IIRC, dellsam34 may have sidebar discussed some SDI specifics in a recent thread.
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    I find this to be very fascinating. Searching around the threads I found DopeNessMonster who uses this exact setup. His equipment is a dream. It consists of a DP-210 transcoder, AJA FS1 frame sync, AJA Kona LHi capture card, and Sony Trinitron reference monitors. Capturing from a Sony 5850 deck.

    https://forum.videohelp.com/threads/400071-U-Matic-capture-project

    That is the one upside to using one of those professional units now that I consider it. You can turn off the TBC entirely. On the AG1980 the TBC cannot be disabled. Correct if wrong but I believe consumer VCR’s have a TBC that cannot be turned off. It gives you more flexibility to run your configuration outside of the unit rather than relying on the internal TBC. Unless they ever manufactured a VCR without a TBC.
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  21. Originally Posted by BenKlesc View Post
    I find this to be very fascinating. Searching around the threads I found DopeNessMonster who uses this exact setup. His equipment is a dream. It consists of a DP-210 transcoder, AJA FS1 frame sync, AJA Kona LHi capture card, and Sony Trinitron reference monitors. Capturing from a Sony 5850 deck.

    https://forum.videohelp.com/threads/400071-U-Matic-capture-project
    Yes, thats a good thread! Glad it continues with updates, as its one of very few discussions I've seen that goes into detail about capture challenges specific to the U-matic format. Despite having worked quite a bit with U-matic in a post production house back in the analog era, I've never attempted to digitize nor been ensnared by the line and frame sync issues that apparently plague digital capture of 3/4" tape. Oddly, I've got a boatload of direct U-matic to VHS second-gen dubs, made by direct connection from a simple Sony player to a consumer VHS vcr. Those tapes are all rock-stable and digitized beautifully with no issues, so its fascinating to me that going direct from first-gen U-matic source to digital capture presents additional problems (granted, the OP of that thread is employing a much higher level hardware chain).

    OTOH, not everything discussed in that thread would apply to VHS capture using the same components. The Sony U-matic decks came in a bewildering variety of configurations, some of which exacerbate line and frame sync issues in a manner not typically encountered with VHS. So, some of those issues explored don't apply to VHS, or would apply to a different degree or unpredictably.

    That is the one upside to using one of those professional units now that I consider it. You can turn off the TBC entirely. On the AG1980 the TBC cannot be disabled. Correct if wrong but I believe consumer VCR’s have a TBC that cannot be turned off. It gives you more flexibility to run your configuration outside of the unit rather than relying on the internal TBC. Unless they ever manufactured a VCR without a TBC.
    You have perhaps misunderstood the many confusing remarks made about these SVHS vcrs over the years, because that assumption is incorrect. All of the SVHS vcrs I've used do allow their TBC to be completely disabled, including the popular AG1980, the many JVC DigiPures and the Mitsubishi DVHS HS-HD2000U. The issue that causes frustration is their annoying coupling of DNR to the TBC function: in most cases, its all or nothing (TBC+DNR together, or not at all: they cannot be switched in or out independently).

    There are many tapes that could benefit greatly from DNR but react badly to the line TBC in these VCRs. Usually the line TBC is very helpful, but on some types of poor tapes (and a handful of seemingly good ones) the TBC overshoots the mark, adding ugly distortions. When this happens, the only cure is to disable the TBC, which unfortunately takes the DNR with it and reduces many of these "premium" VCRs to a performance level worse than some of the better "consumer" VCRs without on board TBC/DNR.

    Complicating things further, there are variable oddball exceptions to the "TBC+DNR all or nothing" rule. One reason the AG1980 is so sought after is its unique ability to disable the line TBC while DNR remains active (great for tapes that need DNR but dislike the TBC). Unfortunately this is a one-sided advantage: while you can get the 1980 DNR without the TBC, you cannot get the 1980 TBC without the DNR, in fact you cannot disable the DNR at all- it is always active. This isn't usually an issue, as the 1980 DNR rarely causes problems, but its a data point to remember when deploying the 1980. Another Panasonic curve ball is PAL vs NTSC, and Japanese domestic NTSC vs North American NTSC: some European PAL equivalents of US/Canada AG1980 allow full independent switching of TBC and DNR. as do a couple of Japanese home-market-only NTSC successors of the AG1980. In North America, we only ever got the one AG1980 model.

    Going the opposite direction, some (possibly all) of the JVC DVHS models include always-active TBC that cannot be disabled, tho in some cases the DNR feature (if included) can be adjusted. According to experts like LordSmurf who've tested them extensively, JVC's DVHS incarnation of TBC/DNR isn't quite the same as the version in their SVHS models: the capture performance of some DVHS JVCs is inferior to their SVHS. In my work, the only DVHS I've used extensively is the Mitsu 2000, which contains a TBC/DNR circuit similar to the JVC SVHS DigiPure (with the same control points and all-or-nothing kill switch). A small number of very picky users have claimed in the past that the Mitsu 2000 TBC/DNR is not as good as JVC's, but IMO it is every bit as good and often better. Where the Mitsu stumbles is EP/SLP (6-hr) tracking and HiFi tracking ability, which is slightly worse than some (but not all) JVCs. This does not bother me, since the majority of "classic" JVCs recommended for capture also suck at EP/SLP tracking and are about as twitchy as the Mitsu with HiFi tracking. JVC did not get better at EP and HiFi tracking until the very few, very late models mfd post-2005 (SR-V10, SR-V101, a couple of prosumer combo decks and some of the DVHS).

    Short version: there are no "magic" VCRs optimized for every possible tape (tho the AG1980 comes darn close). Most of us with a wide variety of tapes to capture find we need a half dozen VCRs to suit differing categories of tape. Things might be easier for your project, which seems to involve only camera-original recordings, all made from the same camcorder. A VCR that handles a few of these tapes well in pre-flight capture testing should be good for the entire project. I envy you that: having to evaluate the best VCR for each wildly different tape is a huge time sink for me.
    Last edited by orsetto; 7th Apr 2021 at 14:24.
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    One last question I have about these pro units like the 7750. I've been archiving audio tape/reel to reels for my entire life, and generally speaking the best results you will get is from the same machine that was used to record the material. Does this apply to video as well? Would I be better off playing back the tapes in the camcorder I still have they were recorded from and directly capture from the device, and apply an external TBC coming out of the camcorder? Is there any truth to that, that tape will play best on the machine that was used to record it?
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  23. Originally Posted by BenKlesc View Post
    Is there any truth to that, that tape will play best on the machine that was used to record it?
    The original machine, if it hasn't degraded, has the same alignment as when the tape was first recorded. That is the argument for getting a better playback. However, in many cases that "machine" is actually the camcorder, and most camcorders don't have TBC and other circuitry which can extract and reproduce a better picture.

    I have no way of knowing which of these two competing ideas will prevail. So, as always, you'll need to do tests on your own equipment and look carefully at the results to determine which is better.
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  24. As johnmeyer said, it isn't quite as cut and dried with VHS as with some other formats. By and large, the originating VCR or camcorder is long since discarded or no longer functions reliably, so the option of using it is off the table to begin with. A related issue is the fragility of consumer VHS camcorders, and the fact they're more optimized for recording than playback.

    But, your situation is somewhat unique. You still have the original camcorder, and it seems to be in good operating condition, which makes it a possible capturing candidate. So it would be worth running some tests to see if theres any advantage to using it over an alternative VCR. Mostly this would depend on the tracking null point of the tapes: if they're significantly off-spec (esp at EP/SLP), the camcorder will tend to be preferable. If they're nominal, and track with no or minimal adjustment on other VCRs, the advantages of the line TBC/DNR in the AG1980, JVC DigiPures, Mitsu 2000, or a big deck like 7750 can overtake the native tracking advantage of the original camcorder/VCR.

    First-generation camcorder VHS generally presents less of a challenge than material recorded from other sources. Most VHS camcorders had monophonic, linear track audio which is far less twitchy and fussy than HiFi stereo tracks: HiFi tracking variance between decks is one of the biggest headaches many of us deal with. EP/SLP tracking variance is another frequent problem that pops up less often with camcorder material, more commonly shot at easier-tracking SP speed. This again increases your odds of being able to exploit the advantages of decks with TBC/DNR. But you won't know for sure unless you test some of the tapes with a 1980 or JVC DigiPure or 7750 vs the original camcorder with your capture system.

    Assuming tracking performance is equal between camcorder and premium VCR, it will come down to how noisy the tapes are, esp in colorful areas of the image. if they're all clean with minimal noise, the camcorder-as-player should be fine, if they're oversaturated and streaky, a deck with TBC/DNR will tame that nicely. An external frame TBC between camcorder and capture will prevent dropped frames and audio sync drift, but do nothing to improve the appearance of funky-looking tapes: thats where the premium VCRs justify themselves.
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