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  #21  
10-12-2021, 07:42 PM
Teefer Teefer is offline
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Quote:
Originally Posted by timtape View Post
Thanks for the new audio sample. Are you sure this is linear audio recorded in EP? The high frequency response is way too good for LP or EP, and almost too good for SP. But whatever the format, the humming/ buzzing noises are unacceptable. If linear audio, we should hear the tape hiss but not those many tones/harmonics (I counted 27). You might try recording the same sample voice onto your Pana VCR as a comparison. Or even just a playback of this JVC recording on the Pana, event though there will be an azimuth error.

Screenshot attached of the spectral display.
Thanks for the reply.

I made a typographical error! It is recorded in SP. I will modify my post to reflect that typo once the edit button becomes available. I think there's some sort of timer that restricts the edit. I can only confirm it was played back using the 'norm' setting on the OSD. To me, that means the linear audio track is being played back, and it's the only OSD setting that produces this buzzing. It's also the only OSD setting available when playing back all of the tapes in my 80s/90s archive.

I will record the same sample using Panasonic and get back to you.
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  #22  
10-13-2021, 11:47 AM
latreche34 latreche34 is offline
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Here is a sample from my VCR HR-S7600AM from a home recorded tape on an unknown VCR in EP, Note that I boosted the gain slightly to make the noise more apparent, So as you can hear it sounds identical to what your VCR produced on it's own.

I don't know if this is due to filtration capacitors failure in the linear audio playback preamp or JVC stopped caring about linear audio quality at a certain point in the VHS era, I remember hearing the same buzz from CRT TV's from the speaker in the quite passages so it's clearly a blanking pulses noise leakage, I will eventually recap the linear audio section on my VCR's but not in the near future as it is not really important to me.

So even if you proceed with messing the alignment of your VCR's audio head it will not fix the noise. And yes a VCR with Dolby circuit is more devoted to linear audio quality than a VCR who's main focus is Hi-Fi audio.


Attached Files
File Type: mp3 VHS EP Speed Linear Audio.mp3 (1.27 MB, 5 downloads)

https://www.youtube.com/user/latoak34/videos
  #23  
10-13-2021, 12:33 PM
hodgey hodgey is offline
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I'm hearing (and seeing on the spectrum) far less odd noise/interference in that clip compared to the SR-V101US clips and my XVS20 clips.
  #24  
10-13-2021, 03:32 PM
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Quote:
Originally Posted by hodgey View Post
I'm hearing (and seeing on the spectrum) far less odd noise/interference in that clip compared to the SR-V101US clips and my XVS20 clips.
The same type of noise is still audible and its level is high enough to render the recorded audio unacceptable in my opinion.
  #25  
10-13-2021, 04:54 PM
timtape timtape is online now
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Quote:
Originally Posted by Teefer View Post
The same type of noise is still audible and its level is high enough to render the recorded audio unacceptable in my opinion.
Yes in the higher frequencies which an EP linear audio recording cannot make, the many noise bands are added by the playback deck. They will not be in the original recording.

Notice too the loss of (orange coloured) speech audio centred around 3.5 kHz. In that same area, notice how the added noise bands are now more visible (and audible) because there is no program to mask them. Probably caused by an azimuth misalignment in playback.

Both problems, the added noise and the loss of recorded signal, have contributed to weakened signal to noise ratio, as in your camcorder example.
Fixing one problem will help. Fixing both is best.


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File Type: jpg VHS linear audio EP Latreche.jpg (75.5 KB, 12 downloads)
  #26  
10-14-2021, 10:38 PM
timtape timtape is online now
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Spectrum stills are not nearly as good as seeing them as a video clip in real time with the synchronised audio. I found out Win 10 allows mp4 video recording of what's on the PC screen. Here's an example. It's the linear audio of a VHS tape recorded off TV in '93.

I tried to highlight the two main problems we've been discussing here in the OP's JVC playback example:

1. Azimuth misalignment. Lost highs.

Near the beginning of the clip I deliberately misalign the audio head's angle and then return it to aligned. You can hear and see the effect together.

2. Noisy VCR audio playback.

At the end I deliberately pause the tape by pulling the pinch roller away from the tape. For a brief second you can see and hear only the VCR's own background noise. Without the program audio from the tape masking it, the horizontal lines - and the other random noise (blue specks) - are clearer. In an amateur camcorder recording with quiet voices, this noise from the VCR playback could totally mask those quiet voices.

The short dark section right at the end is after the VCR muted the audio when it sensed no tape movement.

Please note there is a few seconds' delay at the beginning of the video before I manage to play the file in the analyzer.



Last edited by timtape; 10-14-2021 at 11:23 PM.
  #27  
12-10-2021, 01:16 PM
hodgey hodgey is offline
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I was testing a little bit on my XVS20 today, first tested replacing the 47uf decoupling capacitor for the audio VCC (power input) on the video/audio IC. Also put in a 0.1 uf one in parallel, which seems to not be installed by default on JVCs for some reason even though there is a spot for one and it's typically what you see on other vcc inputs including the audio one on other vcrs. (I could not however find a ceramic one with the right size so ended up sticking in a through-hold film one instead which may not be ideal.) It did not seem to help however.

Adjusting the head azimuth a tad didn't seem to reduce it any either, it just makes it more/less muffled (could maybe help a little if it's off to give more audio volume compared to noise though but I didn't fine-tune it).

Last thing I discovered was that on my unit, ejecting the DVD drive seemed to also produce a low frequency tone on the linear audio when the dvd drive motor was running (no impact on hi-fi audio), even though as far as I could tell the motor power from it is quite separated from the video/audio ic power line.

Will do some more testing.

(Also I'm sure I saw a thread here recently on similar issues on a related JVC, where turning off the lcd display helped a little, but can't find it right now. Couldn't seem to turn it off on mine, and just cycling through the display modes on it had no impact.)

EDIT: Old thread with sample from a SR-V10U, sounds like same type of noise noise on the playback sample.

Also recently worked on an old JVC HR-S5800E (1991 I think), on that one bad power supply caps caused high frequency whine on linear audio, however it sounded different so I doubt that's the same issue.

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  #28  
12-17-2021, 05:07 PM
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I need to vent here. Certain topics are starting to irritate me these days. This is one of them. We're all getting spoiled rotten video-wise.

The hunt for a single VHS device to do everything perfectly is a fool's errand. Why else do you think us serious folks have 2+ decks? It's not for funsies. We understand that tapes are all unique, due to a wide variation in recording gear/methods. And that necessitates having multiple decks to content with this reality.

You want a deck that cooperates with the widest array of your sources. Yes, most times, that means a JVC S-VHS VCR with line TBC. But sometimes not. It really depends on your collection. Modes, audio, signal stability, etc. When JVC S-VHS is known to be weaker at certain factors, like mono/linear audio, you may need to look to Panasonic S-VHS with line/field TBC. (And if that doesn't work, it gets ugly fast, you'll make compromises using non-SVHS/TBC gear.)

Perspective is also needed. This is two-fold:

(1) I'm not a person that utters the phrase "good enough", because it's almost always used as an excuse for crappy quality. Not just video, but anything -- mopping the floor, painting the house, etc. But there is a point of diminishing returns. Most people are actually fine with slightly degraded audio -- a fact we've all known for ages (MP3, telephones, etc). Not so much with video, visual errors are way more distracting. So this leads into the next issue...

(2) Your VHS home camcorder was a piece of crap. How do I know this? Because they all were. The video sucks, the audio sucks. The end. In general, the video was pretty ghastly, between white balance issues and exposure (and camera shake), made worse by the limitations of VHS (chroma, grain, etc). But the audio was way worse, nothing was ever accurate to the ambiance/music/vocals of the recording setting. The sample audio, in this thread, at the Youtube links, were both lousy. The OP was essentially asking which sucked less. It's sort of like comparing dog poop to cat poop. But it's poop! So trying to squeeze out audio perfection from a media that was never perfect is somewhat silly.

Okay, fine, but you really want to eek out every drop of audio quality off the tape. I'm fine with that. I try too!

However, again, spoiled. Sometimes seeking conversion perfection doesn't come from a single deck. The fix here is easy: capture JVC for video, capture another VCR for audio. Edit back together. Done! (In fact, that may be the cheapest method, using quality gear. A refurb/recapped Panasonic AG1980 will easily cost more than this JVC SR-V101 and a plain VHS VCR that plays the audio well. Also know that the Panasonic isn't better than JVC, just different. There's a good chance that it plays the video worse, so you'd still be capturing JVC video with Panasonic audio.)

But again, how much do you really notice hiss and noise when the original audio was distorted, flat, and tinny? Ideally, yes, do what you can to make it not-terrible.

Alright, I feel better now. Needed saying.

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The following users thank lordsmurf for this useful post: BarryTheCrab (12-17-2021)
  #29  
12-17-2021, 07:06 PM
latreche34 latreche34 is offline
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Quote:
Originally Posted by lordsmurf View Post
Alright, I feel better now. Needed saying.
I agree, That's why I never bothered messing with linear audio for a VCR, It is what it is. I usually do take care of my VCR's in terms of maintenance and cleaning or repair if there is a problem, But I don't go to the trouble of re-aligning its transport to make one tape happy.
  #30  
12-18-2021, 05:28 AM
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Originally Posted by latreche34 View Post
But I don't go to the trouble of re-aligning its transport to make one tape happy.
This! I'm perfectly able to adjust a transport but I won't for the sake of individual tapes providing the quality is 'good enough'. That is just silly.
  #31  
12-18-2021, 09:53 AM
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When I come across tapes with issues, those are set aside for my special decks, including a JVC S-VHS deck (ironically, a SR-V101) that I have for realignment needs. That deck hasn't been properly aligned in years, I just tweak it to match trouble tapes. I do this for work, and for myself.

For audio issues, it's the two-capture method above.

I don't just cram it through a setup, and whatever it spits out is what I accept. That's dipping into low-quality work, no better than the likes of LegacyBox or other low-end careless shops. (If the person doesn't want to pay for special work, that's different. At least the option is there. It's not hidden from them, they're not lied to that it's "not possible to fix".)

You do need to take some care in transfers. My point is that no single perfect VCR exists. And sometimes that means multi-capturing with multiple decks.

We're getting spoiled by HDTVs that play multiple formats, all from a single tiny stick. That's great and all, but it's not videotapes.

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  #32  
12-26-2021, 01:38 PM
Teefer Teefer is offline
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I’ve been holding back out of respect for Lordsmurf’s medical condition, but it’s time that the facts are laid out here since I’m getting zero traction by e-mail over the last 10 weeks. The last post by Lordsmurf makes it clear (in my opinion) that he is not interested in resolving this issue. I paid him back in June 2021 for a workflow and he isn’t resolving a very basic situation for me here. The deck he provided has an overly noisy linear audio circuit. So just replace it or refund me? What’s the big deal? It’s been over 6 months now since I sent the money.

It’s clear that Lordsmurf is not going to advocate for my best interests and that he would rather voice his annoyance because the samples I provided don't meet his standards. Anyone familiar with audio can pick out the noise profile in an instant. High frequency noise in any recording is obvious, especially by comparison. Normally a seller would take the unit back and do the testing themselves, but I know Lordsmurf hasn't been in great health so I have done a lot of the work with the guys on the forum (thank you everyone ). Maybe my samples don't meet Lordsmurf's personal standard, but I've played them for some of the people I work with at the studio and they all agree the noise is as clear as day.

As such, I need to step up and advocate for myself. I’ve spent more than enough time collecting samples, testing tapes and working with the very generous people on this forum to try to diagnose the linear audio circuit issue with this JVC deck. I have been provided no solution by the seller (Lordsmurf), so I need to bring forward the evidence on the matter.

Feel free to read this whole thread from the beginning, but here is a link to the audio sample I recorded on the JVC deck Lordsmurf supplied that shows the unacceptable noise. This noise does not occur with any of my other junker decks, with any source. This is a deck-specific issue.
Specific capture details can also be seen in my Post #19 in this thread. Please note this was recorded in SP mode (not EP as I erroneously stated, but cannot edit) and played back on the same deck that recorded it. All sources playing linear audio on this JVC deck show this noise.

Let’s stop saying this audio issue is source-specific. The deck is not fine. These claims are not supported by the evidence. This is a deflection from the obvious fact that there is unique and obvious noise in the JVC linear audio circuit. I've tested all types of sources and they have the exact same noise profile on this JVC deck. Here’s all of the testing I’ve done with absolutely no change in the noise profile:
  • Tested my home videos, others’ home videos, new clean audio I have recorded through my digital mixer, and I’ve tested brand new retail media from two different eras.
  • Played back audio through two hi-fi systems and in my critical listening room.
  • Powered the unit off of a DC-to-AC UPS, and through an isolation transformer to rule out interference.
  • Powered the unit off of a DC-to-AC UPS, and through an isolation transformer in a completely different geographical location to rule out interference.
  • Compared tested samples for this JVC unit to my junker Panasonic units. Panasonic units do not display this persistent linear audio noise.
  • Recorded linear audio on JVC unit, played back on the same unit to rule out azimuth error. Noise persists. When the linear audio on these tapes is played back on my Panasonic junker decks, the noise is not present.
The linear circuit noise is identical and persistent between all of my tests on the JVC unit and none of my other junker decks display this noise in their linear audio circuits. This is electrical noise that is specific to the JVC’s linear audio circuit. I've also linked this thread from another user that reported the identical noise from their machine. Want to listen? Download the clip in his first post. He concluded that the cause was from electrical interference, but I’ve powered my JVC deck off of a DC-to-AC UPS, and in a completely separate location from my studio. Why is no one commenting on this other user’s audio clip? There is literally another user with the same deck who posted an audio sample whose noise profile is identical to mine, and states that it only occurs with linear audio (as does mine). This surely is no coincidence. This user concluded it was interference causing his issue, but after doing some detailed testing with my UPS, isolation transformer, and testing in two different geographical locations with no change in the noise profile, it can be concluded that radio or ground loop interference is not causing this issue. After evaluating the preponderance of the evidence, it is most reasonable to conclude that the issue is the deck.
Since it’s now been over 6 months since I paid Lordsmurf, it’s time for me to lay out some of the facts:
  • I paid Lordsmurf for a workflow (deck, TBC and capture card) on June 9, 2021 and it didn’t ship until September 12, 2021.
  • I received it October 9, 2021 and noted the linear circuit noise issue. I contacted Lordsmurf immediately and he said “that is not the deck” with regards to the noise issue. He told me to go to the forums to resolve this. Out of respect for his health, I did.
  • I spent a number of days working with some of the users on the forum (thank you everyone) who agreed that the noise level is unacceptable. I did not have any final resolution on the matter and still had a noisy deck.
  • I contacted Lordsmurf again on October 25th requesting a replacement unit. He said he needs to test a new unit and it takes time. I was patient, once again out of respect for health.
  • I contacted Lordsmurf again on November 8th and he said he does not have a deck ready and isn’t done testing. I was patient, once again out of respect for health.
  • I contacted Lordsmurf again on November 11th and Lordsmurf indicated that the original deck ‘tested perfect’. He asked me to not be pushy and that he “can’t take time to worthlessly communicate” with me when I ask for updates.
  • I contacted Lordsmurf again on December 16th (over a month later now) to check on the status of a deck. It’s not clear what he intends to do to resolve this, but he says he’s burned out on VCR refurb and that he will send a buyer my way for the deck. Why do I need a buyer for my deck? Why can’t this be resolved by the seller?
This isn’t a matter of opinion – this is a matter of fact. Every time linear audio is played back on the JVC deck that Lordsmurf supplied, the same noise profile appears – even with brand new retail tapes – and this does not occur with either of my other two junker decks. And to top this off, we have evidence from another user reporting the exact same issue (in the thread I linked above).

I’ve waited since June for my workflow, and since October 9th for Lordsmurf to resolve this. I believe I’ve been more than patient. Health conditions or not, a seller should actually resolve the issues their customers have, especially when there is clear evidence of the JVC deck having a noisy linear audio circuit. Responding to e-mails without any plans to correct the issue or supply the user with a solution isn’t helpful. If Lordsmurf is too busy to work on a solution, I completely understand. Just take the unit back and refund the money if the deck can’t be replaced. It’s that simple.

How much longer do I need to float around in limbo? It’s been over 6 months since I paid for the unit and I have spent a lot of time trying to diagnose this issue without any resolution. I would like it replaced or the purchase refunded. That's all I've been asking for.
  #33  
12-26-2021, 03:34 PM
latreche34 latreche34 is offline
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While I still think that LS is busy or going through health problems, what would be a fair resolution in my opinion (and I'm not claiming to be a legal expert) is to try to repair the deck with the seller's permission since you said you have some experience repairing electronics and you both agree on a partial refund, If that doesn't work, send the deck to a reputable repair facility after the seller agrees to cover the expenses, Again this is just a personal opinion and that's what I would do exactly if I was a seller. Hope you guys come to an agreement.

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  #34  
12-26-2021, 05:02 PM
hodgey hodgey is offline
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That is provided someone happens to know how to actually fix the issue. Given that we have two users here experiencing the exact same thing I'm experiencing the same noise, and I'm experiencing the exact same problem on two related PAL decks (HR-xVS20, and DR-mx1) from around the same time with very similar (possibly same) ICs and mech I suspect there is some sort of design flaw with these models here (worst case scenario is that the fault is in the main video/audio IC itself). It's clearly more than just not entirely optimal linear audio, if it was that it wouldn't have been a big issue. Like, my LG combo and samsung decks from around the same time doesn't show this sort of noise, and those are not built to a high standard or anything.

Where I have seen a similar symptom is on two slightly older samsung decks, and on my old sony SL-C5 betamax. On the beta one adjusting the playback eq/deemphasis trimmer helped pretty significantly, though that's not something that's adjustable oni newer decks (there may be some chip register settings but nothing accessible). The other slight clue is the user in that an other thread finding that front display setting had some impact on a JVC SVHS (can't find the thread right now'). It does not seem like the same sort of distortion that I've seen from power supply ripple, but can't say for sure, I have an example recording of that from another deck but not at home right now so can't post that yet.

If you do end up sending it to a repair person and they manage to figure out what the issue is I am interested to know what the fault is.

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  #35  
12-26-2021, 06:11 PM
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I'm surprised after the schooling on buying 'unknown units from eBay', which realistically you would have probably had the same level of support from an eBay seller, but at least wouldn't have spent as much.

It's not a small chunk of change here, let's hope you get a resolution soon.
It's Christmas at the moment etc, and my opinion is to give everybody a few days to 'do the right thing' but the fact it appears that this unit is being lined up for another buyer probably raises a few questions.

There are loads of pages on 'the web' about this being a known issue with JVC units from this era as far as I can see.

Let's just hope the right resolution is reached soon. I'm certain it will.
  #36  
12-26-2021, 07:06 PM
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You never replied to my last email.

When dealing with linear audio tapes, you have some options:
- capture video with JVC, capture audio with whatever deck is "playing nice" (ie, your Panasonic deck)
- capture video+audio with Panasonic AG-1980P, but realize it's not a magic fix-all, still failures with either video or audio
- capture with JVC, just accept the audio quality hit
- don't capture, put tapes back in closet

The fact that I (and family) had serious health issues this year (which delayed some shipments, and FYI not COVID) is beside the point here. That has nothing to do with the audio issues.

Your Youtube-butchered audio samples are not useful here. If you want to show case problems, it needs to be human speech, in the captured WAV, not the mic recording ambient sounds. There are ways to recover audio quality. Not just that, but restore it better than original. Hiss is easy to remove, muffled values can be easy to restore. Unlike video, audio loss is not uncorrectable. (BTW: When you say things like "critical listening room", you come across as one of those unreasonable self-described "audiophiles". I'm not playing the nth % game, where a slight difference in tonal quality is deemed "unacceptable".)

If you think you can fix the audio issue, do so. Share your findings here on the forum.

If you want to pay for somebody else to tinker with it, that's on you. And at that point, I won't be able to vouch for the deck anymore, and will not be able to send a buyer your way.

Sometimes JVC audio noise can be corrected in guide realign. Although realign is part of my refurb process, sometimes it can get slip in shipping, the box tossed around too much. And coincidentally the SR-V101 is one of the easiest decks to do this with. The left guide needs the tweak, usually counterclockwise by as much as a full half turn. The problem comes with non-SP tapes, and having to compensate with a right guide tweak. Non-SP tapes showcase audio issues more.

Power issues can be a problem with your grid. When I moved to the TVA grid about 15 years ago, my DataVideo TBCs became noise makers, and I had to switch to all Cypress. When I left TVA, all of the DataVideos were fine again. It wasn't my house, or office, or city, but the whole grid was that way. Consumer UPS with AVR did not clean it enough. BTW, TVA is no longer like that, DataVideo confirmed to work fine there in recent year.

You want a problem "fixed' that is likely inherent, and is in fact something we've all known about for decades now. I knew JVC mono playback wasn't great way back in the 90s. This has been posted about many times in the past 20 years on this site.

I think the issue here is a combination. Feeding linear audio, source based, power based, and possibly even human perception. This would explain why the issue is more pronounced for you than for me.

My power here is relatively clean, I have many sources to test (good mono to bad mono), and my hearing is astute. I did test my full range of mono tapes, in multiple JVC and Panasonic decks. And yes, that took me quite a bit of time. Both JVC and Panasonic had issues with some mono tapes, JVC more than Panasonic. All JVC models performed on par with one another. The SR-V101 is actually a bit better here compared to coveted decks like the 9800 (noting the 9800 is better than the 101 in other areas). So if you find your JVC "unacceptable", you're going to feel that way about any JVC deck.

You're in Canada. Shipping time/costs is a factor here.

As I mentioned in email, if you have all linear tapes, just sell the JVC, go buy a Panasonic AG-1980 instead. I'll send a buyer your way for the JVC. I know the deck is good. Due to family health (and burnout), I've had to mostly step back from VCR work for now. So I don't want to be a middleman to receive and resell a deck right now. I just can't do it. Let me send somebody your way.

@RobustReviews, if you bought a deck from eBay, odds are it wouldn't even play a tape correctly, if it even arrived in one piece. Don't make a bad comparison here. I'm sure Teefer would attest to the quality of the deck playback (excluding linear audio), as well as the quality of shipping (secure packaging, well padded).

And FYI, most of the cost of the workflow goes towards the external TBC. Not the VCR, certainly not the capture card. The TBC is the real "chunk of change" here.

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  #37  
12-27-2021, 04:58 AM
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Quote:
Originally Posted by lordsmurf View Post
I'm not convinced any caps are at fault here.
JVC is a mostly caps-free unit, and didn't use the cheapy Chinese caps that caused issues in Panasonics.
It has to use capacitors, they're a fundamental part of every microelectronics circuit, this shows quite a lack of understanding of electronics if you think the unit is 'mostly cap free' - PSUs, ICs, oscillators, filters, decoupling and a host of fundamental components or paradigms can not work without capacitors, this is just plain silly. There are hundreds of them listed on the BOM for this device! There are several dozen that support the main IC alone.

https://elektrotanya.com/jvc_sr-v101...wnload.html#dl for my source for the manual.

Panasonic did use some junk ones though, that'll I'll agree! But it's simply incorrect to refer to this device as 'mostly caps free', which is beyond the realm of microelectronics as understood by everybody else in the field.

My finger in the air diagnosis is that this is something related to decoupling, classic hallmarks of intrusive noise on to an amplifier but without having it on a bench in front of me take that as nothing more than the ramblings of somebody just posting something on the internet.

Have you tried a self-record/playback on the deck? That'll eliminate a whole host of potential causes and probably open more diagnostic avenues.

My diagnostic order here would be:

Check for noise on self-recording and playback.
Check for noise on recording on the suspect deck played back on another machine.

We can broadly eliminate whole chunks of circuitry here with smart diagnosis.
  #38  
12-27-2021, 05:48 AM
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lordsmurf lordsmurf is offline
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@Robust: What part of mostly did you not understand?

I would also suggest you lack the ability to give an educated guess, since I don't believe that you have lots of experience with JVC decks, nor NTSC video. So your semi-random guess is more random than not.

Your getting passive aggressive with your comments again. Stop it.

About the recording question, I refer to this:
Quote:
Recorded linear audio on JVC unit, played back on the same unit to rule out azimuth error. Noise persists. When the linear audio on these tapes is played back on my Panasonic junker decks, the noise is not present.
But I question that. JVC has no way to specify audio recording method. It dual records both HiFi and linear, like pretty much every other HiFi VCR. And anyway, recording isn't playback. (Yes, some troubleshooting tell-tales, but we're now past that.) JVC has known muffle and hiss/noise in playback, at times, with linear/mono tapes. Not all, just many.

I'm still unable to discern much of anything from the lousy samples submitted here. So I really have no idea how aggressive the tonal loss is. Pretty graphs spit out by analyzer software don't mean much, aside from confirmation that the waveform has noise. I need to hear it, clearly, cleanly.

Linear is an ancient audio recording method, and HiFi decks generally did poorly. Including JVC, but not only. And some were known to playback linear well, mostly Panasonic and rebadges (Samsung, etc).

This still hasn't been addressed:
Why not record quality video with JVC, quality audio with __. Re-merge captures.

Many of us here have had to do this many times over the years. Please do not respond with a Karen/Chad answer (in pouting voice) "I want it to work how I think it should work" (and without having a clue how any of it works). Trying to find a single deck to play every tape perfectly is a fool's errand, especially when dealing with special needs type sources (ie, linear audio videotapes). Certain Panasonic S-VHS decks come close, but not flawless, not without issues or fail rates, and very often expensive money pit decks (AG-1980, etc). Panasonic is not better than JVC, just different.

What I won't be doing is randomly mailing out JVCs, and to Canada no less (international shipping) -- especially when we all know (except for the OP?) that JVC linear audio performance is lesser.

hodgey clearly knows what's what in this thread, having seen the performance of many decks. Probably not anywhere near as many as I have, but still numerous.

Another suggestion: JVC audio playback, in the menu, behaves differently. Try HIFI, MONO, L ONLY, and R ONLY. I've seen where the linear works better in one mode over another. Also some that didn't sound great regardless. And some were fine in all modes. It really is a tape-based issue, whether or not you want to acknowledge it.

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  #39  
12-27-2021, 05:54 AM
RobustReviews RobustReviews is offline
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Quote:
Originally Posted by lordsmurf View Post
@Robust: What part of mostly did you not understand?

I would also suggest you lack the ability to give an educated guess, since I don't believe that you have lots of experience with JVC decks, nor NTSC video. So your semi-random guess is more random than not.

Your getting passive aggressive with your comments again. Stop it.
We must have a different definition of 'mostly'.

How does this use fewer caps than say, an equivalent model from Sony or Panasonic, or anybody else for that matter?

It uses no-more-or-no-fewer by my reckoning than any other? Tell me where I'm wrong!

If you want to know, I have more experience with NTSC video than JVC decks granted but neither I would claim are my forté, but I'm always happy to admit where my knowledge is not strong or I'm just throwing something 'into the ring' so to speak.

I'm still confused what was intended by 'mostly cap free' though?

I'm trying to help diagnose the issue built on many years (albeit quite outdated now) of electronics design and repair - I certainly have enough fundamental small-signal electronics theory rattling around in the head to try and offer some assistance!

===Added - for clarity ===
Just out of interest, reading some of the notes on the schematic, and I'm sure somebody would have piped up and said something, but it is a US model isn't it, not a Japanese import as they have markedly different noise filters?

Last edited by RobustReviews; 12-27-2021 at 06:04 AM. Reason: Added part about US/Japanese model.
  #40  
12-27-2021, 06:10 AM
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lordsmurf lordsmurf is offline
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JVC has far fewer caps, a single board, and rarely has caps issues. When a JVC board has issues, it's usually the board itself has fizzled out. And even then, that's uncommon. With JVC, motors give out more, DDs break, band loosen, lube dries, alignment drifts (gravity, shipping jostles, etc).

I just opened my own 101, and it has 14 visible electrolyte caps. You can't see easily under the transport, so let's just double that to 30 caps total. Panasonic probably has about that many on just the board with the LEDs (clock, etc). It's ridiculous how horribly built Panasonic S-VHS decks were.

If you can offer assistance, I'm all for it. But do it to advance the advice being given so far. Not in some ploy to make yourself seem superior. Sometimes your commentary is very snide and passive aggressive -- something I'm very familiar with in recent years, and I constantly have to tell both of them to cut that shit out. Zero patience for it these days. I like you, I really do. So proceed. I'm pretty sure you do know more than I do about general electronics, but again I'm no dummy. All ears.

I'd offer to remove the transport on my "dirty deck" (also a 101), and take photos. But I think you'd learn more from the service manual anyway. Pretty sure that's what hodgey has done.

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