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  #1  
04-29-2017, 09:12 PM
Koen Koen is offline
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Hi

I have several JVC VHS recorders that occasionally/often/always (depending on the machine) produce faint clicking noises from the mono track (stereo is not affected).

Here's a video.

https://youtu.be/oFhWloVoJgk

There are several of these clicking noises in the video - the clearest example occurs around the 19'' mark.

BTW, I know the audio is noisy as hell, is missing much of the higher frequencies and that the picture is slightly stretched - but those are problems I can rectify myself.

I'm capping lots of VHS and this example was taken from a JVC I use almost daily. It started 'clicking' a few weeks ago and now does it always. Two more JVC's I have had for years do it occasionally.

There are two other things I feel I need to add:

1) I often get a buzzing noise on caps from mono VHS, with the buzz usually starting a few minutes after I've left the house (weird). It usually goes on for anything between, say, fifteen minutes and two hours. Again, I don't get this when capping stereo tapes. This may affect all machines I use, which are not limited to JVC.

2) About two thirds of the Panasonic machines I own are gathering dust. I'm not using them because they often produce random white streaks. It has been suggested in the past this is caused by static electricity building up around the head drum, caused by malfunctioning anti static brushes.

Putting all this together - clicking mono, buzz when out, white streaks - I'm starting to wonder whether there's something 'wrong' with the electricity I'm using and/or some other environmental elements round here, rather than my recorders. Please bear in mind I like to be reasonably critical about my transfers but I know very little about the technological side of electronics and electricity, so there may be something very obvious I'm just not noticing, and/or I may be saying some rather stupid things!

Things I have been wondering are:
-Could the A/C head have become charged by me adjusting the screws? (I use non-magnetic screwdrivers for this.)
-Would there be any point in getting myself a small anti static brush and stroking the A/C head with it for whatever time it takes to 'uncharge' it?
-Could there be something wrong with the electricity network in the house, causing the electricity to become 'dirty' (to use an extremely non-technical term)?
-Could one of the many machines I have linked up cause the trouble? (Computer, TV set, amplifier, loudspeakers and several stacked VHS machines.)

I tried to identify the source of the buzz on one occasion when it occurred when I was home by unplugging the various components one by one - no luck.

The house is sixty years old but most of the wiring has been replaced in recent years. As far as I know everything between the point where the electricity enters the house and the room where I'm working has been renewed post 2000 or so, but there are other rooms that still have the original fifties or sixties sockets, in case that matters.

Any help/suggestions gratefully received!

Thanks for reading.
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  #2  
04-30-2017, 01:01 PM
bever bever is offline
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When I got my JVC HR-S2901U vcr and was checking it out there were streaks in the picture which I made better by cleaning the video heads. Still 2 thin streaks which even when I put the top cover on did not go away. I picked up the vcr and held it 2 feet away from the tv and the streaks went away. I had proven the TV was causing the streaks.Lets call that tv a source RFI radio frequency interference
Static electricity comes from relative movement of two static generating materials. Such as a rubber drive belt and pulley. Maybe the tape itself. Static generation is affected by humidity. I forget whether it is directly proportional or the other way lol

Quote:
-Could the A/C head have become charged by me adjusting the screws? (I use non-magnetic screwdrivers for this.)
-Would there be any point in getting myself a small anti static brush and stroking the A/C head with it for whatever time it takes to 'uncharge' it?
-Could there be something wrong with the electricity network in the house, causing the electricity to become 'dirty' (to use an extremely non-technical term)?
-Could one of the many machines I have linked up cause the trouble? (Computer, TV set, amplifier, loudspeakers and several stacked VHS machines.
charged? I dont think so. only batteries and capacitors hold a charge. What did you mean A/C head?
small brush? maybe only help for a moment
electricity network? possibly not good ground or hope not arcing in the wiring
many machines? well if they were unplugged they are not radiating so not in that case

Quote:
have several JVC VHS recorders that occasionally/often/always (depending on the machine) produce faint clicking noises from the mono track
The odds are in your favor that not all your machines have the same ailment


btw call me a rookie but am not discerning the faint clicking noises from your youtube video
things to try is use a different monitor, a different computer or no computer, a different room in the house or at a friends house.
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  #3  
04-30-2017, 05:48 PM
JVRaines JVRaines is offline
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Quote:
Originally Posted by Koen View Post
Could the A/C head have become charged by me adjusting the screws? (I use non-magnetic screwdrivers for this.)
The head is connected to circuit ground and will not have a charge unless the ground is faulty.
Quote:
Would there be any point in getting myself a small anti static brush and stroking the A/C head with it for whatever time it takes to 'uncharge' it?
No.
Quote:
Could there be something wrong with the electricity network in the house, causing the electricity to become 'dirty' (to use an extremely non-technical term)?
Sort of. You could be picking up arcing switches (EMI) somewhere in the vicinity. Even next door.
Quote:
Could one of the many machines I have linked up cause the trouble? (Computer, TV set, amplifier, loudspeakers and several stacked VHS machines.)
You might pick up digital clocking EMI if your VCR is very close to the computer.

Did you mess with the height of the A/C head? You may have set it too high or low (I forget which) and you are picking up video sync pulses in your audio, which would explain the buzzing. If the misadjustment is very slight, the buzz will come and go with minute changes in tracking.
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04-30-2017, 09:38 PM
Koen Koen is offline
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Thanks to both of you for your most helpful replies.

I've uploaded another, perhaps somewhat clearer clip. From a different JVC, recorded a few years ago.

https://www.youtube.com/watch?v=KDRb...ature=youtu.be

Clicking at 2', 10', 11' and 14' (plus a few more that are not as easy to hear).

@Bever
Yes, I know having a VCR close to a TV set can cause interference. It’s why I have a space of around two feet between the TV and the cupboard housing my VCR’s.

I have read static electricity is more likely In dry areas. I’ve been wondering whether I should try to place a damp cloth in the cupboard, but one of the things that’s holding me back is that I don’t want my machines to turn into rust!

A/C head = mono Audio and sync Control head (I think).

I switched to a new computer monitor a few weeks ago, so can rule that out as a cause. Checking in other rooms/houses and with the computer turned off would be somewhat more complicated, although not impossible.


@JVRaines
My VCR’s are around six feet away from the computer. That’s probably far enough for them not to be ‘very close’ to the computer.

I’m copying tapes I’ve picked up from several people over the last couple of years, and some recordings are rather out of spec. So yes I’m frequently playing around with the A/C head, but I think the adjustments should be small enough not to pick up buzz the way you describe – must admit I’ve never experienced that anyway (although I have two machines that buzz all the time on mono, even when they head is adjusted for maximum frequency response, so I’m assuming that those machines are just mechanically faulty).

On a more general note, thanks to both of you for putting some of the more outlandish things I was thinking of out of my head. :-)

Must say, however, that the possibility of electric arcs somewhere down the line sounds like a bugger of a problem to identify!

Last edited by Koen; 04-30-2017 at 10:19 PM.
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  #5  
04-30-2017, 10:44 PM
Koen Koen is offline
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I should perhaps add that you sometimes hear such clicks when turning off a light. I did just that earlier today while wearing headphones and heard a click. Thought I'd mention that.

Something else: I use a Panasonic DMR-ES10 as a pass-through (I know that's not everyone's cup of tea). A couple of months ago, the one I'm using started emitting a faint high-pitched sound when it's turned off (well, stand-by). At least some of the clicking predates that (perhaps not the buzzing when out, not so sure). That can't be related, can it?
I have two DMR-ES10's in storage, so could try swapping the one that's currently in the chain...
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  #6  
05-01-2017, 01:46 AM
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lordsmurf lordsmurf is offline
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Those noises are probably bad capacitors. The ES10, like the JVC DR-M10/100 LSI recorders, and the AG-1980P VCR, all have caps issues. Just get them fixed, and all will be well.

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  #7  
05-01-2017, 09:05 AM
JVRaines JVRaines is offline
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Quote:
Originally Posted by Koen View Post
So yes I’m frequently playing around with the A/C head, but I think the adjustments should be small enough not to pick up buzz the way you describe – must admit I’ve never experienced that anyway (although I have two machines that buzz all the time on mono, even when they head is adjusted for maximum frequency response, so I’m assuming that those machines are just mechanically faulty).
Are you adjusting the head for azimuth? You could be rotating the audio pole pieces far enough to catch video tracks. The audio track is only 1 mm wide, including guard band. I must admit I have never come across a VHS recording so out-of-spec that I had to realign the A/C head.

If you are using the composite output, you may be experiencing sync buzz, which can occur with excessive video levels.
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05-01-2017, 01:38 PM
Koen Koen is offline
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Quote:
Originally Posted by lordsmurf View Post
Those noises are probably bad capacitors. The ES10, like the JVC DR-M10/100 LSI recorders, and the AG-1980P VCR, all have caps issues. Just get them fixed, and all will be well.
As I said I could try swapping the ES10 I'm currently using for another one (complicated to rewire everything in such a small space, but nothing insurmountable) but I'd have thought that if the ES10 were at fault I woudl hear the clicks no matter what recorder I was recording from, rather than only certain machines and only when using the mono track...?

Quote:
Originally Posted by JVRaines View Post
Are you adjusting the head for azimuth? You could be rotating the audio pole pieces far enough to catch video tracks. The audio track is only 1 mm wide, including guard band. I must admit I have never come across a VHS recording so out-of-spec that I had to realign the A/C head.

If you are using the composite output, you may be experiencing sync buzz, which can occur with excessive video levels.
I wish I were as lucky as you, I frequently feel the need to adjust the A/C head. In fact, a collection I'm working on has many tapes that feature recordings from different machines, at least two of which must have been slightly out of spec. Such fun, ahem...

I've uploaded a buzzing video! Buzz present for the first 8 seconds, then abruptly goes away...

https://www.youtube.com/watch?v=F1JX...ature=youtu.be

Thanks both for the replies, by the way. :-)
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  #9  
05-01-2017, 02:00 PM
JVRaines JVRaines is offline
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That's quite a low-level buzz. You must be listening to it cranked in the 'phones. I see a spike near 15.7 kHz, which is close to the video line frequency.
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  #10  
05-01-2017, 02:24 PM
Koen Koen is offline
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Thanks for taking the effort of analysing the buzz! You're right, this one isn't all that obvious. Some are slightly louder, although not that much. (Besides, I wouldn't have any terrible examples available anyway, as I would redo such a problematic transfer straightaway.)

And yes, I do use headphones to check the sound - there's too much I'd miss otherwise (or I'm just using crap speakers). A slightly misaligned A/C head may sound OK through loudspeakers (for me anyway) but headphones do reveal there's something just not entirely right...

By the way, there are rare occasions where a buzz is not only picked up by my transfer equipment, but also comes through the loudspeakers that are active most of the time here to drone out background noise made by passing traffic. This, however, has only happened a few times - something like half a dozen occasions over the past year or so.
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  #11  
05-03-2017, 03:54 AM
Quasipal Quasipal is offline
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Modern VCR's are downright poor concerning linear audio quality - recording it and playing it back. Muffled, buzz, faint etc. Its a cheap head and circuitry left on for legacy reasons. No manufacturer was better than another from 1995 on - all had problems. JVC with poor top end and weak bass (boxy sound), Panasonic with poor EQ giving weak midrange. Sometimes a cheap off brand manufacturer like Orion made one that performed decently but this was almost by accident. Main issues are:

Playback level - so you have to amplify the sound more and so pick up other crud which is VCR generated.
Playback EQ - sound is of poor quality with uneven frequency response.
Cheap head - cheaply manufactured heads will not play back with best possible sound.
Alignment issues - if you look, there is no tape guides on the head stack. It relies on accurate tape alignment from the post adjacent and the exit guide from the head. Any scrimping in quality will allow the tape to drift.
Azimuth - this is important as you have found, but often you are fighting against all the above issues too.

Sound is often just as important as vision and so I have invested quite a bit of time and effort in getting this as good as possible. I have found that the studio AG decks (not the prosumer ones, the actual studio models) have linear sound that is way above the consumer VCR's - however well they are specced - so I keep them around, even though they are not as good at some other aspects of video playback. They also have stereo sound on linear along with Dolby B.

Take a listen to linear audio on AG here https://www.dropbox.com/s/656c8q9kkx...001_2.WAV?dl=0 which I made as a demo.

Once you mess with head stack height and tilt you have pretty well messed up the deck, but azimuth can be adjusted. Trouble is there are three screws, none labeled, so to be sure you need the service manual so the others are not touched. Not always obvious. If height is adjusted you will be into the guard band etc. Also mono machines playing stereo tapes get into phasing errors which mess with the sound too. You will be 'playing' the peak of one phase on one channel and the trough of the other channel with the same head - impossible!
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05-03-2017, 11:07 PM
Koen Koen is offline
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Thanks for that. Must admit EQ is not something I've especially paid attention to - perhaps I'm thinking too much along the lines of 'if high is OK, all is fine', which may be a bit too simplistic. Just another thing to look out for, then.

I agree cheap & chearful players can sometimes be surprisingly good for mono audio. I don't know where in the world you are but here in Europe Philips churned out some pretty rough machines around the turn of the century. They reportedly break down easily due to poor construction and the picture is so fuzzy you that it makes SP look like LP, but the mono sound is better than average.

(And, for my money, although they are nowhere to be seen in people's lists of favourite VCR's, the ones Orion made around the same time are reasonably good, too. They could be a tad sharper and the colours are slightly 'milky' but otherwise they produce a picture not too much unlike what you get from a JVC. And they're rather forgiving for dropouts, too. Pity they don't track stereo especially well, even more so because they insist on displaying a 'HI-FI' message (that can't be turned off in the menu!) when they lose and subsequently find again the stereo track...)

For what it's worth, when I feel the need to adjust the A/C head I go for an azimuth screw, simply because it's easier to get the head into a position where it delivers sound that's acceptable to me. Also, because with azimuth (unlike height) you basically never have to make as much as a complete 360 degree turn of the screw, it's possible to mark it with a pen and then take a picture of it with my phone. Makes it very easy to get everything back close to the original position afterwards...

"Also mono machines playing stereo tapes get into phasing errors which mess with the sound too. You will be 'playing' the peak of one phase on one channel and the trough of the other channel with the same head - impossible!"
Does this refer to adjusting the A/C head of a standard machine offering only linear mono when playing back a tape that contains linear stereo? If not you've lost me here, I'm sorry. :-)
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05-04-2017, 03:43 AM
Quasipal Quasipal is offline
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Quote:
Originally Posted by Koen View Post
Thanks for that. Must admit EQ is not something I've especially paid attention to - perhaps I'm thinking too much along the lines of 'if high is OK, all is fine', which may be a bit too simplistic. Just another thing to look out for, then.

Yes, Eq is worth the time. Trouble is if you boost it post VCR you will be working from a poor quality if the VCR is not right in this area - better to get it right in VCR using one with better sound - and save you time. Like you I thought best highs meant best sound, but its not that simple. I noticed this when playing back over the TV - sound seemed muddy yet with sibilance

I agree cheap & chearful players can sometimes be surprisingly good for mono audio. I don't know where in the world you are but here in Europe Philips churned out some pretty rough machines around the turn of the century. They reportedly break down easily due to poor construction and the picture is so fuzzy you that it makes SP look like LP, but the mono sound is better than average.

Yes, I use some Philips machines just for this reason - and even LP audio is better than some

(And, for my money, although they are nowhere to be seen in people's lists of favourite VCR's, the ones Orion made around the same time are reasonably good, too. They could be a tad sharper and the colours are slightly 'milky' but otherwise they produce a picture not too much unlike what you get from a JVC. And they're rather forgiving for dropouts, too. Pity they don't track stereo especially well, even more so because they insist on displaying a 'HI-FI' message (that can't be turned off in the menu!) when they lose and subsequently find again the stereo track...)

My Nan's old Orion mono recordings are astonishingly good - shame about the rest of the VCR!

For what it's worth, when I feel the need to adjust the A/C head I go for an azimuth screw, simply because it's easier to get the head into a position where it delivers sound that's acceptable to me. Also, because with azimuth (unlike height) you basically never have to make as much as a complete 360 degree turn of the screw, it's possible to mark it with a pen and then take a picture of it with my phone. Makes it very easy to get everything back close to the original position afterwards...

Sounds perfect - only tiny adjustments are needed on the azimuth usually

"Also mono machines playing stereo tapes get into phasing errors which mess with the sound too. You will be 'playing' the peak of one phase on one channel and the trough of the other channel with the same head - impossible!"
Does this refer to adjusting the A/C head of a standard machine offering only linear mono when playing back a tape that contains linear stereo? If not you've lost me here, I'm sorry. :-)
Think that if you have two distinctly separate stereo tracks and you are running them over a summing (mono) head then when it plays music or any audio with a stereo separation (different signal in the left and right channels) then you will get some mangling of the sound. Play linear stereo tapes on linear stereo VCR's when possible.

I realised my link did not work. Try this https://www.dropbox.com/s/k4bde0mrcl...001_2.WAV?dl=0 which is linear audio I recorded and played back. If you have some stereo speakers use those.
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05-04-2017, 08:43 PM
Koen Koen is offline
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Thanks for your comments and the Dropbox file. That really sounds astonishingly good for linear audio, and the fact it's stereo very much adds to the 'experience'. I listened to it using headphones, by the way.
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05-05-2017, 04:06 AM
Quasipal Quasipal is offline
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Quote:
Originally Posted by Koen View Post
Thanks for your comments and the Dropbox file. That really sounds astonishingly good for linear audio, and the fact it's stereo very much adds to the 'experience'. I listened to it using headphones, by the way.
I did that as an experiment on how good linear audio can be - a sort of reference. I have read so many times how bad it is - muffled and hissy - so wanted to find out for myself.

I have also found out that many VCR's record linear audio better than they play it back - I get better sound on a 1980's deck when playing back a 90's/00's linear mono recording than playing it on the deck that recorded it - the opposite of HiFi playback.

For mono I use a 1986 Ferguson Videostar 3V55 (rebadged JVC). You can hear the linear mono performance of that here https://www.youtube.com/watch?v=Nq6aqkiB3fE
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05-05-2017, 10:42 PM
Koen Koen is offline
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Thanks for that clip. As you say, mono from VHS needn't be quite as bad as some people like to think!
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