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  1. I recently acquired a nicely refurbished EDV-9000 from Yahoo! Auctions Japan and also picked up a Nissho voltage converter to go with it. I'm using the s-video out from the EDV-9000 to go into my Panasonic DMR-ES10 and then S-Video out from there to an AIW Radeon 7500 AGP card. I noticed that my transfers are all showing these little white streaks from time-to-time, all in different places, which I learned from this thread are apparently called dropouts: https://forum.videohelp.com/threads/308778-Best-way-to-mask-dropouts-on-old-Betamax-recordings. At first I thought it might just be old tapes and oxidation, but even the test tape which seemed "like new" is showing dropouts here and there so I started to wonder.

    In that linked thread, jagabo mentions cleaning a spring, and cym found one to clean on the Panasonic AG-1980. Any idea where this might be on the EDV-9000? It's not on top of the head assembly unfortunately like the AG-1980. See my attached photo of the head assembly on my EDV-9000. Image
    [Attachment 70731 - Click to enlarge]


    Do you think just cleaning the heads could help with the dropouts? I've been hesitant to clean the heads because this Beta is so different from my JVC VHS. I found what I think is a pretty good video that shows cleaning the Betamax: https://www.youtube.com/watch?v=l78OfaL3Qvw.

    Two questions on that video:

    1. Aren't the heads only supposed to be turned counterclockwise? I see them going both ways in this video but maybe it doesn't matter on Beta.
    2. Is it really necessary to use MG Chemicals AV Head Cleaning solution and MG Head Cleaning swabs? I'm more than happy to get these if they're needed, but I've been cleaning my JVC VHS heads with printer paper folded over and moistened with 70% Isopropyl Alcohol, and so far, so good. I can see how the heads are kind of sticking out on the Beta and might require more care. I'd love to hear from someone who's actually cleaned these types of heads before I go and mess something up

    Thanks again for all the wisdom shared here! What a great community of helpful folks.
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  2. Capturing Memories dellsam34's Avatar
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    No, that problem has nothing to do with cleaning, I had an EDV-7500 that exhibited the same problem and took the entire head assembly a part and cleaned it and lubricated it and the fault did not go away, I'm still uncertain to what causes those white comets on Beta machines. I noticed the bearings were noisy in my machine which I tried to figure out how to pull them out but gave up, How's the condition of the bearings on your machine? do you hear noise from the drum assembly? I currently have a Canadian clone to the EDV-7500, the EDV-7300 that doesn't have the problem and the head spins smooth with no noise at all.
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  3. White streaks/coments can be other things than dropouts, e.g grounding problems as discussed in that thread. The ones in the first screenshot looks like something else. Lack of good head disc grounding can cause static buildup resulting in random comets/blips like this while with some other issues typically they will be in the same spot each playback (e.g dropouts that aren't masked properly) and/or occur on sharp transitions between black/white (worn heads, misadjusted rf filters). though I haven't quite figured out how that works or where that is in most of the betamax vcrs.

    Dropouts is dips/sections of missing signal on the tape which VCRs generally can detect compensate for by (in most vcrs) replacing the output at those spots with video from 1 line back. Sometimes on somewhat older (up to mid 80s) vcrs the dropout detection can need a bit of adjustment to correctly pick them up though this one might be new enough for that to not be an issue.
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  4. I don't hear any noise from the drum assembly, and this machine was sold to me as "very low use", so hopefully the bearings are good.

    I double-checked the test tape, and the comets on playback are definitely in different spots every time, so it's not something in the recording itself.

    I'm leaning pretty strongly towards some type of grounding issue. It looks like this is a known issue with Sonys. They even used to sell a grounding kit to solve the problem! See https://www.palsite.com/pcat_gndkit.html. Also, see http://www.palsite.com/950tech.html#static for mention of an anti-static plastic sheet, which I think is in place on my unit (see the shiny rectangle in the lower right of my picture). Mr. Betamax also mentions a grounding repair at https://mrbetamax.com/GroundingRepair.htm.

    I'm sure those grounding kits are no longer available, but maybe Mr. Betamax sells something similar? I've dropped him a line to try to find out.

    In the meantime, if anyone else any other ideas on how to fix this possible grounding issue, I'm all ears! Thanks!
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  5. Here's a picture from the Mr. Betamax site of the grounding kit in place and the parts to the right that made up the kit.

    Image
    [Attachment 70745 - Click to enlarge]


    If anyone here has this kit or something similar for sale, or knows where to buy this, please share with the group
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  6. Capturing Memories dellsam34's Avatar
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    Since your problem is not bearing failure I really do hope that it's just ground strap problem, On my previous machine I cleaned and made sure it has a firm connection but it did not fix the problem. You do need to remove the flying erase head rotary connector to get to the head drum, Yours is an editing machine that's why it has that and check that connector as well it could be also the cause of the problem.
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  7. The grounding kit looks similar to the type of ground carbon brush used on VHS up to the mid 90s (and a bit on video8), so it might be possible to repurpose one from a scrap VHS deck. Alternatively maybe one could make some make-shift thing from a motor carbon ground brush since those are widely available.
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  8. I'm a Super Moderator johns0's Avatar
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    It's head wear,i replaced beta heads for the same problem years ago and it fixed the issue.
    I think,therefore i am a hamster.
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  9. Thanks for that suggestion oln, I will look around a bit and see if I can find a ground carbon brush on an old VHS deck I could salvage.

    johns0, if the issue turns out to be worn heads, replacement heads would have to be salvaged from another less used EDV-9000/9300/9500, right? Are there other units as well that would have matching heads, maybe the EDV-7000/7300/7500? I'm fairly competent at electronics repair, but I'm honestly not sure I'm up to replacing the heads, that sounds like a daunting task and one that leaves little room for error.
    Last edited by theseeker2; 4th May 2023 at 18:58.
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  10. Is there such a thing as a test tape that helps determine whether heads need to be replaced?
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  11. I'm a Super Moderator johns0's Avatar
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    Nope.
    I think,therefore i am a hamster.
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  12. I have two of these machines imported from Japan, the first one had loads of broken solders on the bottom PCB, especially on the connectors. The second nicer machine was just as unstable so I run it on a variac set to about 93-95v. The machines works flawlessly and runs a bit cooler this way. I suspect due to the age, there's some components that are well overdue and the machines have less tolerance to higher line voltage. Got two SL-HF1000's and they both will not work on 100v, but works fine on 99v. It really is that specific in my case.

    The EDV machines ranged from working fine for a short while to completely loosing speed control after being run for about 1 hour with loss of Hifi audio in between.
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  13. Originally Posted by theseeker2 View Post
    Is there such a thing as a test tape that helps determine whether heads need to be replaced?
    There existed video head tester thingies back in the day but they're probably extremely hard to find these days.
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  14. Capturing Memories dellsam34's Avatar
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    I don't quite understand what that guage measures, certainly not mechanical head wear which is the OP's concern, Head coil can either pass or fail meaning open or closed, I have never heard that the head coil changes resistance over time. There are guages that measure head protrusion if one knows the specs since heads tend to recede when they wear out.

    That's not how head wear is measured by the manufacturer though, Since head wear is directly proportional to RF level, Technicians use special test tapes and observe the width of the RF envelope, RF level meters do exist if one doesn't have an oscilloscope which leads me to believe the guy in the above video is using the guage the wrong way, RF level suppose to be checked while playing a test tape and connect the meter leads to the test points of the head RF on the RF preamp board and that's probably how that tool is used.

    Some pro tape players have RF VU meters on them so when they pop in a studio tape they can check the condition of the deck from the test section at the begining of each tape to make sure everything is in order before rolling.
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  15. I'm a Super Moderator johns0's Avatar
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    Test tapes can never measure head wear and electronic tests on head wear were never trusted since any amount of electronic waste can screw up results.
    I think,therefore i am a hamster.
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  16. Capturing Memories dellsam34's Avatar
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    Head condition can be translated into RF signal strength while playing back a tape, When the head wears out it recesses, therefore it puts less pressure on the magnetic tape which results in a weaker RF signal, The signal weakness or should I say strength can be easily measured by an oscilloscopes or RF a meter using a special test tape as a signal reference, You cannot measure RF level using a home video cassette or a pre recorded tape because those tapes don't have a steady and well calibrated signal on them, Although they can be indicators but not reference.

    Some re-adjust tape tension to increase tape to head contact pressure but it is never recommended as it wears out the drum, But since Beta uses head disc and stationary drum assembly, the drum wear is not a big concern like in other formats that use rotary drum assemblies.
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  17. I'm nervous about readjusting the tape tension, sounds like something that could be easily screwed up, but I may go that route if needed.

    The variac is an interesting idea, the unit does run pretty hot, even at 100V with the Nissho voltage converter.

    I also have a weird issue with the beginning of every tape showing up in a red hue. My JVC VHS definitely doesn't do this. Could it be related to the dropouts? Here's a video to explain what I mean: https://www.youtube.com/watch?v=2CBTnrxldB4.
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  18. Capturing Memories dellsam34's Avatar
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    I wouldn't mess with any mechanical adjustement until knowing for sure what the issue is, Check this video if you have the same problem, He fixed his by changing some capacitors.
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  19. Thanks for the link to the Betamax Man's video, @dellsam34. He does end up making a huge improvement in his repair, but in the end he has basically the same problem as me, that the little white streaks or comets are pretty much all over the place on playback.

    It does seem like the streaking gets worse the longer I play the tape. So if I just capture the tape in 10 or 15 minute intervals at a time, I get a lot less dropouts. The unit was supposedly completely recapped, but I wonder if a cap or two is bad or wasn't recapped just right. I also wonder if I did lower the voltage just a bit with a Variac if that would go easier on the capacitors and resolve the issue.

    Can I use a Variac alongside the Nissho voltage converter? Any recommendations on where to buy a Variac these days?
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  20. Both Changing behaviour depending on how long the unit is on, and that red tint at the start could possibly a cap issue (though usually it gets better after warming up rather than worse.) I could see grounding problems/static also changing with playtime though so hard to say.
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  21. Capturing Memories dellsam34's Avatar
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    Originally Posted by theseeker2 View Post
    Thanks for the link to the Betamax Man's video, @dellsam34. He does end up making a huge improvement in his repair, but in the end he has basically the same problem as me, that the little white streaks or comets are pretty much all over the place on playback.
    He seem to have fixed the problem entirely, check the other tape he put on, it was noise free, Keep in mind that Beta format didn't live long to have an advanced tape drop out compensation (DOC) like VHS where noisy segments are replaced by good segments from adjacent lines in problematic tapes.
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  22. DOC replacing video from one line back is present in all betamax and vhs vcr afaik. Though, at least for VHS the detection of dropouts improved a bit over time. Older ones up to maybe the mid 80s have the dropout threshold set manually which often needs some adjustment, later ones seem to handle that automatically. Early ones also had the dropout compensator on the rf signal while later ones combined it with the noise reduction function so it was done after demodulation.

    A handful of later vcrs featured digital DOC but that was pretty rare and even most SVHS decks did not have this. Seems it might have been more common on 8mm devices.

    Anyhow, the comet tails here are not dropouts that will be caught by dropout compensation.
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  23. Capturing Memories dellsam34's Avatar
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    I was referring to the dropouts in the attached YT video where the OP was thinking the comets issue wasn't fixed by that YT member, but they were mostly tape dropouts, I did not say Beta doesn't have DOC, I said it wasn't advanced like VHS, Even the top models such as the ED Betas which I have one have very primitive DOC for maybe one or two lines, and almost every tape has them due to age.
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    theseeker2:
    Is problem fix?
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  25. The red tint issue must have been somehow related to my AIW Radeon 7500 AGP card, because I didn't get that when capturing with a ATI USB 600.

    Unfortunately the more serious issue of the dropouts/streaks/whatever you want to call it was never resolved. The issue actually got worse the more tapes I played.

    The conclusion: buyer beware, even on Japanese Yahoo auctions. The unit did seem spotless and well cared for, and it was recapped as stated, but none of that can overcome a worn video head, and that is not an easy (or cheap) problem to solve. So I'm unfortunately just going to have to make do with what I've got.
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    Originally Posted by johns0 View Post
    Test tapes can never measure head wear and electronic tests on head wear were never trusted since any amount of electronic waste can screw up results.
    I used to see the Sony techs use a test tape and an oscilloscope to test my machines and would tell me that my heads are worn or will soon need to be replaced. Not sure what they were looking for. I fully trusted them because I had so many machines and got to know them well. They would even come out from the back because even the counter people knew me. They'd say "You're back?" , "Yeah, but a different machine!"

    Edit: BTW, I know that professional machines have an hours counter and they use that for head cleaning maintenance and head replacement. Maybe there was a hidden counter inside consumer machines?

    Edit 2: Also, the heads replacement wasn't about getting money. This was the local Sony distributor and they even did some free repairs for me, including head replacement because I had so many machines and they would say they shouldn't have worn out so soon. I used my machines a lot! I suspect using the Betascan added to the quick wear.

    Edit 3: To add to my history with the techs. I got my first machine in 1981 and met the first Hawaii trained tech and became somewhat close. Over the years, he moved up in rank and left word with his junior techs to take care of me.

    To be clear, I'm not questioning your expertise and statement that the test tapes couldn't measure head wear, but they were used for something as a quick test. Sony used to have free Betamax clinics where customers could bring in their machine to their in-store setup and they'd have the tape and oscilloscope there.
    Last edited by lingyi; 23rd Aug 2023 at 12:24.
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