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  1. Member
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    Hi guys, I've been searching around for a way to get the recorded signal from a VCR while recording. Is it possible in any way?
    I want to monitor the recorded signal, from the tape, while recording. I am artist/hacker/tinkerer and it could be neat to be able to use the VCR as a "live" video effect.
    I've seen people make tape loops with VCRs so if it's in no way possible to do this, on any machine, maybe one could record the signal on one deck, send it into another deck and play it back, with some delay of course (which I don't mind)

    Link to VHS tape-loop:
    https://www.youtube.com/watch?v=ASex_ZPYwPk

    Best,
    Dogenigt
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  2. Member Cornucopia's Avatar
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    Iirc, On standard consumer decks, there are 2, or 4, or 5, or 6 heads. They are in pairs except for the 5th head which was used for "trick play", or non- standard motion options (slomo, fastmo).
    1st pair = standard play (SP) Record/Play, sometimes also extended/superlong play (EP/SLP) record/play
    2nd pair = long play (LP) record/play, also sometimes ep/slp r/p
    3rd pair = hifi audio r/p

    The need for different heads for different speeds has to do with signal optimization because the different speeds change their angle of travel on the tape.
    So one cannot really use one as a substitute like you intend.

    With that in mind, I don't see you being able to do what you want with consumer & commercial decks without MAJOR reworking of the innards. Better polish up your EE and ME degrees.


    Scott
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  3. I'm a Super Moderator johns0's Avatar
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    Why would you want to get the output from a vcr head while recording?If it could be done there would be instants of it in google.The signal goes directly to a video tape so it would be much easier to get the signal going to the vcr and view it or send it,
    I think,therefore i am a hamster.
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  4. Member Cornucopia's Avatar
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    Plus, the way the rotating heads work with the tape path, there is really only 1 head travelling past the tape at a given instant. It's not like you could fast-switch alternating heads or something - there just isn't enough contact with the tape to do that.

    The idea of passing the tape from one machine to another is also a bit far-fetched. You woud have to have a quite complex arrangement of modded cassettes, tension relief, guide rollers, etc. A true Rube Goldberg device. For what? A delay device? Remember, the true tape speed is quite low, so going from machine to machine would add a heck of a lot of delay. That could easily be done just by delaying the incoming signal. Or by playing back afterward.

    I wouldn't touch this project with a ten foot pole. Not worth the effort.


    Scott
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  5. Capturing Memories dellsam34's Avatar
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    Only pro decks had this feature (Betacam decks) and it is not for the purpose you are seeking, It is for minimizing generational loss during tape editing, So a pair of heads would read the signal recorded on tape and mix it with the incoming signal and send the mixed signal to a second pair of heads that follows the first pair with a flying erase head in between to erase the signal that has been just read by the first pair and lay down the new mixed track on tape. This would normally require two tapes and two decks which mean a loss of quality but Sony came up with this idea to minimize the quality loss and also save money on buying more decks. I will post a link to a YouTube video about this.

    I suppose you can use one of those decks the way you want by just not mixing any signal to the original signal but the delay is not going to be noticeable, a field or two is the most.

    Here you go, I found it:
    https://youtu.be/_puGWzBmljM
    Last edited by dellsam34; 18th Dec 2021 at 08:54.
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  6. Member
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    Originally Posted by dellsam34 View Post
    Only pro decks had this feature (Betacam decks) and it is not for the purpose you are seeking, It is for minimizing generational loss during tape editing, So a pair of heads would read the signal recorded on tape and mix it with the incoming signal and send the mixed signal to a second pair of heads that follows the first pair with a flying erase head in between to erase the signal that has been just read by the first pair and lay down the new mixed track on tape. This would normally require two tapes and two decks which mean a loss of quality but Sony came up with this idea to minimize the quality loss and also save money on buying more decks. I will post a link to a YouTube video about this.

    I suppose you can use one of those decks the way you want by just not mixing any signal to the original signal but the delay is not going to be noticeable, a field or two is the most.

    Here you go, I found it:
    https://youtu.be/_puGWzBmljM
    Thanks a lot! very educational video! Will look into beta-machines with this pre-read function. Did I understand it correctly that you can output the recorded signal with this dynamic read function after it has passed the rec head? Or only pre-read from the read head BEFORE the rec head? Any analog tape VCR machines with this functionality? I'll go scouting, thanks again.
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  7. Capturing Memories dellsam34's Avatar
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    I don't exactly know the nuts and bolts of the pre-read feature but the user manual should explain it in details, I believe only digital decks have this feature however some are backward compatible with analog Betacam recording so not sure if the feature can record analog video or just digital Beta.
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  8. Member Cornucopia's Avatar
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    Note again that those are pro, broadcast-level, component BetaCam (or DigiBeta) decks, not consumer y/c color-under BetaMax decks.

    They cost $8-10k at minimum and well over $100(200?)k at maximum. From memory, am pretty sure the BVW (broadcast) line of Sony optionally had that capability, but the more economical PVW (production/commercial) line had neither of those as options. Certainly not consumer decks.

    What dellsam34 mentioned has both confidence heads (after record, for review), and pre-read heads (for optional preview, FX edits). Preread heads never got real popular, because anybody who could afford already a deck like this, along with the videomixer/switcher, monitors & peripherals, likely could also afford to just get a standard BVW and a few extra PVWs as source decks, and be able to have an easier time of setting up and doing the edits the normal way.


    Scott
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  9. Capturing Memories dellsam34's Avatar
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    The cost then, Now they can be had for almost nothing depends on where you live obviously. eBay prices are inflated and do not represent the true value of the item, Most people who buy old gear from eBay buy it for nostalgia purposes hence the inflated prices for stuff that has no real purpose today. I mean take a look at this one, who would buy it for that much and for what purpose?
    Last edited by dellsam34; 20th Dec 2021 at 00:52.
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  10. Member Cornucopia's Avatar
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    Gear like that has lots of hidden costs WRT support. That particular deck looks beat up. Getting back into optimal working order will very likely cost (in addition) 2x-3x times what it appears to be going for, mainly because of the rarity of replacement parts, and the skill ($$) necessary to properly fix & set up. And as I said before, these decks don't work in isolation - mixer/switchers, genlock, TBCs, etc, with "timed" cabling between - are all necessary to get out of this deck what is expected/intended.


    Scott
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  11. Capturing Memories dellsam34's Avatar
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    When I was presented with few Betacam SP tapes to convert to digital files I had to find the smallest and cheapest deck I could find that can playback at least one or two SD formats and keep getting more decks for other formats as the need arises, It turned out Sony did make small (size of consumer VCR), cheap and multi-tape compatible decks for all analog and SD digital Betacam format for both small and large cassettes (Betacam, BetacamSP, DigiBeta, BetacamSX, MpegIMX), Sony J30-SDI and Sony J3-SDI, not only that, they equiped the decks with state of the art ADC for analog tapes with TBC, DNR and Dolby C decoder for tapes with such audio encoding. The deck outputs digita SDI and can be transfered to PC with an after market SDI/USB3 adapter.

    So what those microwave size decks accomplish today? I don't know, Besides nostalgia maybe some people are still recording on them.
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