Completely remove VCR head switching noise?

[DarkStar]

I've been met with a bit of a dilemma. I have two VCR's; a Panasonic PV V4021, and a Sony SLV-779 HF. I'm passing through a Panasonic DMR-ES45V to kind of stabilize the signal a bit, and it's cleaned up the head switching noise quite a bit. I'm not sure if there are any VCR's that have virtually none of it, and my current budget to get another VCR is exhausted.

I noticed that if I combined captures from each of the two VCR's they seem to clean it up completely as they have different points where it's distorted. Does anyone go through the hassle of trying to completely clean it up? I'm currently trying to digitize my old tapes and was hoping to do this once and for all before they go bad.

Some comparison screens I did:
002.png
Panasonic PV V4021

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Sony SLV-779HF

001.png
Panasonic over Sony

[Aya_Rei]

Larteche can comment further but from my understanding it is possible to adjust the head switching noise by adjusting some part of the VCR. But it's a risky process so it's best to not bother with it unless you know what you are doing.

From the VCRs I have the difference between head switching noise for SP mode tapes are like 1 to 2 pixels, it ain't that huge. I tend to crop the bottom by 8 or 10 pixels anyway.

LP and EP mode tapes, such as this example is where the Panasonic AG-1980 is better than my JVCs.

JVC SR MV-45U
JVCNFLExtreme.png

Panasonic AG-1980

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This is something VHS-Decode could in theory solve but despite their claims of a "clean head switching signal" that doesn't appear to be the case at all. Sometimes decode captures have worse (more) head switching noise.

[latreche34]

VHS-decode reads the RF from the VCR, so it doesn't have a way to improve it, If the VCR's RF point is off for a given tape, VHS-decode will pick it up as is.

I would not recommend adjusting the switch point for every individual tape even if it's possible, But if you have a special tape that you want to maximize its output it can be done, Consult the service manual of your VCR, Some have mechanical tweaking, others have an electronic trim pot, Be aware that changing the switch point can affect other signals on the tape such as HiFi audio, or other modes such as LP.

[DarkStar]

Quote:

Originally Posted by Aya_Rei

Larteche can comment further but from my understanding it is possible to adjust the head switching noise by adjusting some part of the VCR. But it's a risky process so it's best to not bother with it unless you know what you are doing.

From the VCRs I have the difference between head switching noise for SP mode tapes are like 1 to 2 pixels, it ain't that huge. I tend to crop the bottom by 8 or 10 pixels anyway.

LP and EP mode tapes, such as this example is where the Panasonic AG-1980 is better than my JVCs.

JVC SR MV-45U
Attachment 20146

Panasonic AG-1980
Attachment 20147

This is something VHS-Decode could in theory solve but despite their claims of a "clean head switching signal" that doesn't appear to be the case at all. Sometimes decode captures have worse (more) head switching noise.

Wow, that's pretty good on the Panasonic. Is there any softening filter on that JVC VCR? The Panasonic screen look quite a bit more detailed as well.

[Aya_Rei]

Quote:

Originally Posted by DarkStar

Wow, that's pretty good on the Panasonic. Is there any softening filter on that JVC VCR? The Panasonic screen look quite a bit more detailed as well.

For LP/EP the 1980 is better than the JVCs I have as both of my JVC VCRs (which in comparison to each other the differences are nitpicking levels of minor) have a softer image in those modes.

Though keep it in mind separate video heads are used for EP compared to SP.

The other image comparison was with an SP Mode tape, where the quality differences are basically nothing besides a small hue difference. There ain't a big change there.

Both VCRs were set to EDIT mode which turns off some noise reduction from the deck.

[Feedbucket]

I've done both, and a combination of both. My JVC HR-S3912 fails when it encounters certain hues of red, so I designated that the junker deck (though it still works fine otherwise) and manually re-oriented the drum so that the head switch is out of frame. The MV45 produces a better image, but I don't want to mess with its internals without a better handle of the full implications, so instead I just get a regular capture from that and overlay the switching noise with the complete lines from a 3912 capture of the same source. It's time consuming and maybe OCD-level dumb since it involves getting two captures and making sure their frames are aligned temporally.

Personally I'd say moving the switch point manually is not the worst idea in the world, especially if you want to capture once, Just Get It Done and move on with your life, but do observe the caveats that latreche mentioned and be comfortable with the idea that you're touching something you probably shouldn't be.

Forgot to mention - I did find that I needed some kind of stabilization after moving the drum past a certain point. I used an ES15. YMMV.

[lordsmurf]

Quote:

Originally Posted by Feedbucket

I've done both, and a combination of both. My JVC HR-S3912 fails when it encounters certain hues of red, so I designated that the junker deck (though it still works fine otherwise) and manually re-oriented the drum so that the head switch is out of frame. The MV45 produces a better image, but I don't want to mess with its internals without a better handle of the full implications, so instead I just get a regular capture from that and overlay the switching noise with the complete lines from a 3912 capture of the same source. It's time consuming and maybe OCD-level dumb since it involves getting two captures and making sure their frames are aligned temporally.
Personally I'd say moving the switch point manually is not the worst idea in the world, especially if you want to capture once, Just Get It Done and move on with your life, but do observe the caveats that latreche mentioned and be comfortable with the idea that you're touching something you probably shouldn't be.
Forgot to mention - I did find that I needed some kind of stabilization after moving the drum past a certain point. I used an ES15. YMMV.

Some posts need a "super thanks" for the added input. The is worth $2.

Quote:

Originally Posted by Aya_Rei

This is something VHS-Decode could in theory solve but despite their claims of a "clean head switching signal" that doesn't appear to be the case at all. Sometimes decode captures have worse (more) head switching noise.

I don't even know why you mentioned it. vhs-decode makes lots of claims, but fall flat in actuality. This site really doesn't concern itself with low-end hobbyists tinkering/soldering on thrift store VCRs. We're interested in quality video, using quality methods, that give quality results.

As latreche34 has properly stated, it just uses the RF pickup in the deck. But if the deck sucks, the RF sucks, and the modulated signal sucks.

Overscan noises are inherent to tape, and some % of head-switching will always exist from the source recording VCRs. Even contact method will have residual from the master tapes. At very most, you can minimize playback head-switching noise, but it comes at a cost, as Feedbucket has shown in his excellent anecdote.

In 99.99% of cases, trying to remove head-switching noise is overly OCD. Just capture, mask, move on. These tapes are never the Zapruder film, where every grain between the sprocket matters.

Quote:

Originally Posted by DarkStar

Wow, that's pretty good on the Panasonic. Is there any softening filter on that JVC VCR? The Panasonic screen look quite a bit more detailed as well.

Just be aware that source tapes matter. AG-1980P is not a panacea to remove head-switching. Sometimes it's even worse than JVC decks. It depends on many factors. I would not suggest getting an AG-1980P only for this reason, you may find yourself disappointed at the costs. Great deck, but only buy when needed, as it has heavy nasty maintenance costs.

[aramkolt]

One other thing to keep in mind that is that second or more generation tapes will very likely have some head switching noise baked in. Even some small batch commercial tapes were made with tape duplicators and likely won't benefit nearly as much from head switching noise adjustments.

I don't recommended changing the head switching point on AG1980's mainly because from what I've read, if you move it too much, it can start to mess with the HiFi Audio which is something you'd definitely notice (if it happens) in your capture. On the SR-MV series in particular, it is pretty easy to do since it is just loosening the two screws of the board on top of the drum and moving it slightly as it plays to minimize the noise, so I wouldn't hesitate as much with experimenting on that one.

Some models just have less head switching noise in general. The JVC BR-S (822, 825, 622, 625 - DXU in the part number means it definteily has the TBC option) have very minimal head switching noise, but also has settings to change it within menus. I wouldn't make the JVC BR-S your primary VCR though since it can only play SP tapes and looks a bit oversharpened to me personally with some slight ringing (may or may not bother you). Finally, I'll say that those BR-S often will need some pretty involved refurbishing mechanism wise and they weigh something like 50lbs and are absolutely huge, which increases the risk of shipping damage. W-VHS machines also have relatively minimal head switching noise, but they tend to need heavy refurbishing before they are really usable and most of the readily available versions require voltage stepdown as they were much more widely adopted in Japan which uses 100VAC. The WVHS improvement in head switching noise doesn't have anything to do with the actual W-VHS circuitry since the W-VHS processing boards can be removed completely to still give the same playback of Non-W-VHS tapes, but it does perhaps have something to do with the 5 pairs of reading heads which might more accurately tell the

[DarkStar]

Thank you all for the helpful answers. I bit the bullet and adjusted the head switching point on the Panasonic PV V4021 VCR since it's one where I could just loosen and move the circuit board atop the head. I moved it a bit counter clockwise and it lessened the noise below the screen considerably. I hardly see any for my TV recordings. Also thankfully no stuttering. I think this would probably be for me the best for now with my current setup.