Deter's AG-1980 Repair Service

[lordsmurf]

The TBC on or off will create a slight color shift in the picture. The greater the difference usually means a problem.
Unlike the JVC decks these AG-1980's always play back slightly different than the next.

This is something we need to discuss sometime. I'm somewhat certain the pots on the boards control the levels. Like a lot of other brands of gear (DataVideo, Elite Video, etc), board settings are not documented. Line TBC should not alter color, and in fact does not do so on JVC decks, ES10/15, or anything else. It's a Panasonic problem. At very worst, if pots are all-or-none, it should be calibrated to the TBC being on, not off.

I disassembled an AG-1980 some months ago (a deck I've had for years, has never worked, already partially disassembled), took quite a few photos so you and I could discuss privately. The darker TBC image issue has always bothered me. But time keeps getting away from me. That was also the first time I'd taken apart an AG-1980 in about 10 years. I didn't remember it being so frustrating, with everything inside being such a delicate flower. A lot of the rubber, plastic, and wiring has aged badly in these.

I personally don't want to deal with tgrant machines anymore. Granted he puts stickers all over the place and really cleans the insides and the capacitor work seems to be fine but so much of the other stuff on the machines that I reworked was absolutely screwed up and a nightmare to try to figure out the problems.

TGrant was more interested in hiding deck repair info than sharing it -- including BS about super secret methods, blah blah blah, replace the damned caps and done, as you correctly stated. I think he knows how to correctly adjust the levels for the TBC, but will only do it for you, not tell you, and for the huge fee that is nothing more than bandaid on a gaping wound (ie, only fixing then-bad caps, not future guaranteed bad caps). I'm just so extremely disappointed by his work, and out thousands of dollars for new repairs that should have never been required, at least not within a few years, with minimal deck use.

I hate these decks now. Money pits. But a necessary evil for quality, for more stubborn tapes. If you don't truly need an AG-1980, and get one anyway, seek help, you're into self-punishment. With few exceptions, such as deter's total rebuilds.

[Deter]

LordSmurf,

It is impossible for me to calibrate an internal TBC on these Panasonic units. I fix the Y/C card and re do the boards that is it so it produces the effects it was designed to do. If one is really compulsively obsessed with this, you can swap out the Y/C card from a similar AG unit and it works fine. I did a bunch of AG-1970's years ago and they don't have the video card and I was pretty impressed with the picture.

Last year, I don't know the model number but this guy sent me a high end Panasonic from Japan. It looked like the JVC's from the appearance and the unit even had a DNR filter. It also had a TBC built in. Not only that it produced really good color levels so I had a few problem tapes that didn't work that well on my units. So I used that guys VCR to record my tapes I was like OMG this is great cause I will never get this chance again. I will be honest it was pretty hard working through the menus and stuff cause everything was in Japanese but by testing things you figure it out.

[Deter]

One last things, this guy wanted me to give him step by step instructions on like skype to rebuild a machine. Are you kidding me? That is insane. First thing you need to learn is how to build or fix the loading mechanism and tape transport. Than it is like playing lego's you have to be able to pull the entire unit apart and put it back together. With interchangeable parts you can use other parts from the same type of unit. Than you got to know how to fix the boards and not wreck them. Two years ago for work I needed another I-Phone, I don't know anything about I-Phones. I purchased $20 worth of parts and built myself an I-Phone for $20. What I can tell you is this, those screws are tinny. If you understand the basics and what part goes here and how to plug in the camera using the ports it really was not that hard. Once you do it once the next time you get a bit quicker. No I am not doing phone repair or anything like that.....

[Deter]

So you do all this work and ship the unit back and the shipping company breaks the machine than you file an insurance claim and they never pay. Had two spare units but used these parts on other machines. This is really not that hard to fix but with no extra parts it is impossible. FedEx did this twice last year on these front panels, the 1st one was worse than this but I had the parts.


[Attachment 63880 - Click to enlarge]


[Attachment 63881 - Click to enlarge]


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[Attachment 63883 - Click to enlarge]

[lordsmurf]

LordSmurf,
It is impossible for me to calibrate an internal TBC on these Panasonic units.

I don't think it's the TBC itself, but rather pots adjustments for the signal path either before or after the TBC. It's worth investigating. TGrant was able to further remove chroma noise, and properly set deck luma. The cNR was probably just fixing more caps, but the deck luma has to be an adjustment somewhere. I don't think that was a caps based adjustment, and I believe that's what he told us.

Last year, I don't know the model number but this guy sent me a high end Panasonic from Japan. It looked like the JVC's

Was it a W-VHS deck, like the SR-W5U. It has a reputation for some interesting things, but also for often being irreparable. Hence why rare decks.

So you do all this work and ship the unit back and the shipping company breaks the machine than you file an insurance claim and they never pay.

What carrier, what insurer?
Fedex for both?
Part of the problem is packaging. You have to package decks understanding that hamfisted goons handle boxes. Those Lowe's heavy duty moving boxes are pretty good. You can also double box, and the larger heavy duty boxes from Sam's Club outside the Lowe's box. I've had to do this several times, especially shipping USA>Canada, where the contents are both larger and heavier.

One last things, this guy wanted me to give him step by step instructions on like skype to rebuild a machine. Are you kidding me?

Ridiculous.

[oln]

Was it a W-VHS deck, like the SR-W5U. It has a reputation for some interesting things, but also for often being irreparable. Hence why rare decks.

Maybe something like the NV-SB900 or NV-SB770? Both seem related to the NV-HS960 released in PAL regions with Z mechanism and "digital process". The Japanese market seems to have gotten a bunch of interesting vcr variants that never had direct equivalents outside Japan, especially top of the line ones, like the earlier JVC SVHS decks with "629TBC"( i.e HR-X5), Sony SVHS/dv combo decks with TBC (e.g WV-DR7) and many other very fancy decks.

TBC on/off level is never going to look 100% exact, as whatever is receiving the video output may react slightly different to the raw video sync pulses from the tape, and the much sharper ones that will be present if the TBC is active and is replacing them, even if the levels look to be at the same place on scope output. May be extra complicated on the 1980P due to the use of digital processing for much more than 99% of other vcrs.

[daveemory]

You know what's a far superior solution? Buying an actual TBC unit from eBay and forgetting the circuit in the AG1980. They are doorstops, as far as the buying public is concerned, and can be had for very little money. I bought a NOS Prime Image FreezeII for $65 a couple years back. It is a double unit in a single rack space, for processing two different streams. It's great.

After (painfully) learning that the AG1980 isn't linear stereo, after all, I will happily be saying goodbye to mine as soon as I get my JVC repaired.

[daveemory]

So you do all this work and ship the unit back and the shipping company breaks the machine than you file an insurance claim and they never pay.

What carrier, what insurer?
Fedex for both?
Part of the problem is packaging. You have to package decks understanding that hamfisted goons handle boxes. Those Lowe's heavy duty moving boxes are pretty good. You can also double box, and the larger heavy duty boxes from Sam's Club outside the Lowe's box. I've had to do this several times, especially shipping USA>Canada, where the contents are both larger and heavier.

One last things, this guy wanted me to give him step by step instructions on like skype to rebuild a machine. Are you kidding me?

Ridiculous.

The first machine Deter fixed for me came back with a smashed front door via FedEx Ground. Deter did as good a job packing it as is possible, outside of double boxing it. It was very well padded. FedEx refused my claim. I've had two things destroyed by FedEx in 20 prior years, and both times, they paid the claim. So it sucked.

[lordsmurf]

You know what's a far superior solution? Buying an actual TBC unit

External TBCs are frame sync TBCs.
The internal TBC on the Panasonic AG-1980 is field, essentially multi-line.
Line and frame do completely different tasks, interframe and intraframe.

from eBay

eBay is gambling, not buying. It's become a video dumping ground in recent past years, full of crap that gets bought and resold all the time. The terms "tested" and "working" are nonsense, because seeing power LEDs doesn't mean it works, and seeing any picture (good or bad) isn't tested. There's also a lot of weasel terms, like "pulled from working environment" which means they have no idea if it works or even powers on. eBay is where newbies lose money on bad buys.

and forgetting the circuit in the AG1980. They are doorstops, as far as the buying public is concerned,

AG-1980 is a money pit deck, and anything NOT refurb'd is indeed 99% likely a doorstop until repaired.

and can be had for very little money.

Broken AG-1980 decks have always cost about $200, and it's only gone up in recent years.

I bought a NOS Prime Image FreezeII for $65 a couple years back. It is a double unit in a single rack space, for processing two different streams. It's great.

Those units have issues. It was only worth $65.

After (painfully) learning that the AG1980 isn't linear stereo, after all, I will happily be saying goodbye to mine as soon as I get my JVC repaired.

JVC doesn't work well with linear either. Worse, actually. It depends on factors, not a simple binary yes/no situation when it comes to linear audio playback.

[daveemory]

Actually, I was suggesting that external TBCs are doorstops, as far as the buying public is concerned.

A frame sync TBC such as my suggestion is often needed, in my experience, to go between a source and a capture card (i.e. the AJA systems). The line sync method of the AG1980 isn't sufficient. So I'm seeing less and less reason to need to use Panasonic's TBC.

Curious as to know what the known issues are with the Prime Image FreezeII. I've got two externals – forgetting the maker of the other one at present, and it's at my studio – and have consistently had more pleasing results with the Prime Image.

[lordsmurf]

Actually, I was suggesting that external TBCs are doorstops, as far as the buying public is concerned..

The uneducated public doesn't even know these devices exist. Many are convinced that VHS looks bad, not understanding that their equipment is what sucks, and the tape probably actually looks quite decent with proper playback (ie, good VCRs, TBCs)..

A frame sync TBC such as my suggestion is often needed, ...The line sync method of the AG1980 isn't sufficient.

Correct. Line TBC isn't frame TBC. Line cleans the image, frame cleans the signal. You need both.

So I'm seeing less and less reason to need to use Panasonic's TBC.

Panasonic often has field TBC, which is essentially multi-line, which is why it can be stronger than JVC type line TBCs. The line/field are needed to correct the visual timing errors of the image, aka wiggly pictures. All VHS wiggles without TBC, to varying degrees, and varying locations (aka top-screen tearing).

Curious as to know what the known issues are with the Prime Image FreezeII. I've got two externals – forgetting the maker of the other one at present, and it's at my studio – and have consistently had more pleasing results with the Prime Image

I've actually forgotten. But it's something. I'd have to search past topics on the subject, both here and digitalFAQ.com forums, to remember. But I know it related to the expected input NOT being consumer analog formats like VHS, as the root cause. But I forget the exact issue here. Those "pizza box" broadcast TBCs all have issues on VHS, which is far dirtier and more erratic than expected. (Ironic, because some do well with U-matic, equally dirty, and yet in a different way from VHS. So maybe not too ironic.) After you do this stuff for literally 30 years now, 20+ with most known models of TBCs, some things really do blend together. I just remember the Cliff's Notes: avoid.

[Deter]

Just a few updates:

Please don't send units that are nuts and bolts aka machines that have been heavily tampered with, unless you want to donate them for parts.

Inflation:

As all of you noticed the costs have skyrocketed for everything, however the AG-1980 repair costs are staying the same a flat $500 only do when the unit is fixed. If we can't fix the machine, you pay nothing. Pricing on other VCR's do vary on the unit and work that needs to be done.

FedEx on my end is out as a delivery option however now have an account with UPS and get a slight discount on shipping. Emailing return labels is the preferred return shipping method.

Each return unit is now professionally packaged by a shipping supply store at no cost to the customer. That way all units are bubble wrapped the best they can be.

Spare Parts

Replaceable parts is the key to rebuilding these units. If the boards are cracked, the front panel smashed, the loading bay missing parts or broken gears, damage to the power supply, Y/C card tampered with beyond repair and ect. Just like fixing a car with a bad timing belt or blown gasket the only way to fix the problem is to replace the part.

My spare parts are getting low and if the unit needs new boards or a new loading mechanism and I don't have it the customer has to supply a spare machine. If people in this community want to donate spare units you can PM my account and I will pay for the shipping and handling. This is just to help reduce costs for the members on the overall repair. I am seeing junk machines selling for $400 on ebay.

Warranty

Adding in a one year warranty on all work done and any future problems that may arise with the units. That goes for past customers as well. Never have turned down anyone on a return and always fixed the issues for free the customer just has to pay for shipping both ways.

This is with in reason, you drop the unit off a 5 story building well that is out.

Final Update

Right now getting in to the busy season for repairs so get your units in ASAP so they can get shipped back on a pretty good turn around. In the past had to turn down repairs because the back log was too great with machines sitting on the bench.

[Powerpak]

Is there a place to post working units for sale on the forums??
I would rather avoid places like EBay if I can.

I picked up a good working unit last year and have used it 8-10 times to capture off video from tapes. I can confirm that it plays the tapes through the BNC out and RCA out (never tested any of the other connections). Everything I tested on the front panel seems to work. Display seems to work as well. It also has a good working original remote.
I am moving soon and I don't want to have to worry about trying to pack this one up.

[nicholasserra]

I've recommended a few times opening a marketplace subforum on here and it was always shot down. I say post it at dFAQ.

[Deter]

Here is the deal, what is this now 14 years of dealing with AG-1980 or AG-1970 units?

Have looked at over 250 machines, only one unit in that span was in perfect working order, even on that machine the heads needed to be completely cleaned. The unit that worked perfect someone went in and fixed the Y/C card and did a good job on capacitor replacement and a few other things. In other words every AG unit goes bad over time.

When I started, someone told me the AG-1980's are the best machines, so I got one, took the VCR to several repair shops, after 6 months the unit I got back was never fixed and than soon after other things would go bad. This guy was an expert and could never fully fix this machine and the other guy couldn't fix it at all.

Doing video work and capturing recordings takes a lot of time than you get your recording complete and than later find some crazy error in the picture like it is too dark or random noise lines or some strange problem you didn't pick up.

For me my goal, these recordings were important and wanted the best possible capture quality or even just playing the machine normal and just watching old tapes. So when I got the AG-1980 finally running the way it was supposed to, would have to re-do those captures with the machine errors again.

With this service I take all that out of the equation. Every machine because of the design of these Panasonic's they need to have the boards rebuilt and the Y/C card or else they will never work in the manor they are suppose to.

Yes some repair guys can get these units working really good but others absolutely screw up the machines.

This system I got running at Deter's repair shop took years to develop and now it is running really good. Was able to do things that I didn't think was possible like rebuilding smashed front panels or completely messed up loading mechanisms. The best was fixing a unit that had a nest of cockroaches.

Not all AG-1980's play the same. Some units do produce a better overall picture than others. Until the unit is fully rebuilt you don't know which ones are the real treasures. If someone sends two units, If one is just amazing aka a treasure, I'll tell them before shipping back. The last unit I did for a member of this site was off the charts good, I should PM him and see if he will write a review on it.

Overall at the end of the day on the electronics side is to get the electrical current working on the correct levels to each and every circuit on the board holding and releasing the charge so than the machine functions properly.

[Quest]

I'm just going to chime in on Deter's repair service, I bought an AG-1980 off Ebay 5 years ago or so. At first It played fine but after a short amount of time, maybe a year the picture would be dark and all messed up unless I left the unit on for a while then it would play ok.
Trying to do captures I also noticed that the audio would clip to the point where it was unbearable unless Hi-Fi was turned off then it played fine.
After another year or so it got to the point where even leaving the unit on would not fix the picture issue and so the VCR was no longer usable.
I contacted Deter and he told me that his schedule was booked and try back after a couple months, I tried again and again his schedule was full.
A few months later I tried again and finally he said he could take my machine, Having read thru the stories of damage in shipping I personally made styrofoam inserts to make sure the unit survived the trip.
He got it undamaged and it took just under a month before it was finished. He had it shipped back in a matter of a few days after he had it finished.
Before he shipped it back he asked for my phone number and sent me some videos of my machine running to ensure me that the audio issue was fixed during his repair.
I got the machine back and it works as good as I hoped it would the audio issue is gone, the picture looks beautiful and I can't say for sure because I never paid it much attention but I swear the front display is brighter than it ever was.

So, Yeah I recommend his service!

[alitek12]

Deter, do you know what causes each unit to not produce the same exact picture quality? Does that refer to things like color output.

For example, if I replace the Y/C board on an AG-1980 with a known good working one, it will fix distortion issues but the colors will be a bit off. I'm wondering if only the original board is aligned and adjusted to output the correct colors.

Here is the deal, what is this now 14 years of dealing with AG-1980 or AG-1970 units?

Have looked at over 250 machines, only one unit in that span was in perfect working order, even on that machine the heads needed to be completely cleaned. The unit that worked perfect someone went in and fixed the Y/C card and did a good job on capacitor replacement and a few other things. In other words every AG unit goes bad over time.

When I started, someone told me the AG-1980's are the best machines, so I got one, took the VCR to several repair shops, after 6 months the unit I got back was never fixed and than soon after other things would go bad. This guy was an expert and could never fully fix this machine and the other guy couldn't fix it at all.

Doing video work and capturing recordings takes a lot of time than you get your recording complete and than later find some crazy error in the picture like it is too dark or random noise lines or some strange problem you didn't pick up.

For me my goal, these recordings were important and wanted the best possible capture quality or even just playing the machine normal and just watching old tapes. So when I got the AG-1980 finally running the way it was supposed to, would have to re-do those captures with the machine errors again.

With this service I take all that out of the equation. Every machine because of the design of these Panasonic's they need to have the boards rebuilt and the Y/C card or else they will never work in the manor they are suppose to.

Yes some repair guys can get these units working really good but others absolutely screw up the machines.

This system I got running at Deter's repair shop took years to develop and now it is running really good. Was able to do things that I didn't think was possible like rebuilding smashed front panels or completely messed up loading mechanisms. The best was fixing a unit that had a nest of cockroaches.

Not all AG-1980's play the same. Some units do produce a better overall picture than others. Until the unit is fully rebuilt you don't know which ones are the real treasures. If someone sends two units, If one is just amazing aka a treasure, I'll tell them before shipping back. The last unit I did for a member of this site was off the charts good, I should PM him and see if he will write a review on it.

Overall at the end of the day on the electronics side is to get the electrical current working on the correct levels to each and every circuit on the board holding and releasing the charge so than the machine functions properly.

[Deter]

alitek12, Every machine is just a tad different the JVC VCR's are more uniform. It is not like one Y/C card is better than the other. I've seen AG-1970's produce really good pictures as well and they don't have a Y/C card. You have the video heads, alignment and other factors. Even the sharpness slider bar. Honesty I have no idea what causes one unit to be better than others. The older models for sure have a lower quality picture from my experience. The overall picture tends to be brighter on these units,

For example I did the unit for Quest and it was like an 11 or 12 at the same time did a unit for a guy in Canada and it was an older model and that one was about an 8.

The rating system I am basing this on is that all the electronics are fixed and working properly. From dealing with hundreds of units when you test one out and when it is off the charts good, you do get the wow factor.

When I was doing video work full time over the winter months I used 4 AG-1980 Units and would test and see which unit played the tape the best.

PS I personally have the best LCD for playing analog material it is only a 720p unit and on some of the newer TV's the VCR stuff is going to look like crap. When I was doing VHS work went through every single TV at Circuit City and found one that was backwards compatible. That was back in 2007 I think.

[alitek12]

Thank you deter for answering, hopefully the unit I sent you will come out nicely. I'm sure it will.

[lordsmurf]

Deter, do you know what causes each unit to not produce the same exact picture quality?

If you look at the underside of the 1980 boards, there are pots that can be adjusted. I don't recall if it's covered in the manual (and do not think it is), and Deter does not mess with those (though I wish he would). But I think this is what controls the values. I'm not sure if TGrant does this, though I have my suspicions he does. I dismantled a botched unit last year (figuring I couldn't break it worse, right?), to look into this, but didn't get very far with it (partially due to lack of time).

Note: Decks do get so screwed up, or out of spec, that Deter has to reject them.

So I'd advise NOT opening anything you want him to fix. Do not try a DIY fix, do not send him random eBay "for parts" crap. It needs to be an unmolested deck that is known to work prior, preferably knowing the lineage (ie, used in a studio until it closed or ceased analog work).

I'm sadly not aware of anybody that can truly rebuild bad AG-1980P decks, and I've looked. So those "for parts" decks may truly be parts only from now on.

Be especially wary of any repair shop/person that wants money up front -- do NOT do it!!! In my 2022 searches for rebuilders, I've encountered several shady shysters with exaggerated claims of repair skills. When I pressed further, it turns out those SOBs knew they could not fix/rebuild the decks, and thought I was a sucker to give them free money. Because I knew the exact issues, and what likely needed to be fixed, it spooked them, as they then knew I couldn't be BS'd. Most likely they'd have given a BS excuse to a newbie, returned the deck at YOUR cost, and pocketed the examination fee.

[alitek12]

This is why I went with a fairly rare opportunity and bought two boxed and sealed NEW OLD STOCK units. I was lucky to find these outside of eBay and the units have no wear outside of some brief testing I did to verify the machines work. Unfortunately for the caps though, they were bad from the start as they are the originals. According to the Serial Numbers on the back, both were manufactured in late 1996 so fairly early units.

Outside of Deter, I only know one other technician that knows these machines well, they are Cameron from avrepair.com. They have rebuilt another machine for me in the past. They are rebuilding the other new old stock AG-1980 I have. It is definitely worth looking into their services too.


Attached is a pic of one of the new old stock AG-1980's after the capacitors have warmed up. The picture looks way worse when you turn it on.

[Deter]

alitek12,

That is a nice looking AG-1980 no scratches or dents. This case study is extremely interesting because these units have never been used and somehow went bad over time. My guess as I told you in the PM that certain capacitors will show up as bad and others will show up as fine than over time the good caps will than go bad. That was kind of the idea of the one year warranty because these units will more than likely need a second working. Again it is all a guess. Changed the methods on the boards a few years ago to stop having to rework units but this is new to me cause I've never seen a brand new unit before.

As far as what LORD SMURF is saying, he sent me nuts and bolts units that were heavily tampered with and I don't have the time to sit and build a lego set VCR out of individual parts. The costs to do those machines are doubled aka $1000 a unit cause it is tons of hours aka labor costs, so they are out. Than a pin may be missing or something else and you may need a scrap unit for the extra materials. Another thing I am not going to mess with pots that can be adjusted or other crazy things that can mess up everything. I fix all the boards, fix any kind of loading issues and even fixed front panels. Don't touch the audio circuits and if the audio doesn't work well will replace the entire port on the back of the machine. If the audio still doesn't work well than maybe the board is cracked or damaged beyond repair.

At the end of the day cause I did video work with all my old tapes is to get the units to the same quality that I would have used myself when doing video transfers and that is getting rid of all the errors spoke on in these posts so the errors the person than has to deal with is the video tape itself and not defects in the machine.

[alitek12]

Yep, the new old stock unit is definitely a little different than your usual used AG-1980 with bad caps. While the video has gone, the PSU makes no hiss noise and the clock is very bright. Also the actual mechanics are very smooth and quiet which I've never seen this nice on a 1980. So it seems like some of the common caps have gone bad but not all of them. You'll probably get a better look of it once you get a chance to work on it.

[jgardner]

I just had a great experience with getting one of our AG-1980 machines repaired by Deter. With the TBC switched on, the VCR had been having an issue where the image would start rapidly shifting right to left, along with the gamma levels suddenly dropping or rising over the course of a second or two, but this error has finally stopped. I work at a film archive where we digitize a lot of home movies and home videos, so it's been nice to be able to again capture SLP and LP tapes in good quality (for SLP and LP at least).

[nesburf]

I also just had a great experience with Deter repairing my AG-1980P. Highly recommended!

[Deter]

Thanks for all the positive feedback.

One of the issues I do want to address is the darken TBC this has been a common theme with many units of late.

Color calibration tool is used to set these levels for the machines in general.

With the TBC sometimes someone has mis adjusted these settings on the board or it can be something else.

TBC on or off the actual color levels may vary, but I try to get them pretty close.

On all the machines using a uniform method of calibration so all the units are pretty close to what they should be. You can play with some of the settings on the VCR aka the sharpness slider for picture output.

All the general errors which happen with these units are fixed so you are getting the best possible output out of the VCR. Stress this over and over pretty much every unit that ever existed needs to be rebuilt. Once you get one of these units fully fixed you got a better running and working VCR than anyone else who has one of these.

Fixing these units you have other problems as well like problems in the front panel or loading issues or tape transport mechanism problems that is all part of rebuilding these machines and all covered in the base repair cost.

Some of the error codes that show up are usually dirt or dust or something basic. It is kind of like the check engine light on your car faulting a problem that is not really a problem. Pressing FF or RW while the tape is playing can trigger this. Even just cleaning the heads can fix some of the error codes, I use the dry head cleaner for cleaning my personal units.

Something as stupid as the screw on the left front casing can create loading problems.

[vol.2]

[QUOTE=orsetto;2631314]

The 4990 and its two followups are almost impossible to find now in any condition:

Hi, I have a 4990 that I've been storing for many, many years now after the HI-FI stereo stopped working all of a sudden. I have been using a PV-9451 since then (which still works just fine!), but I decided to dig into the 4990 and get it up to snuff if possible.

I actually tried to take it to a tech about ~15 years ago and was told to "leave it alone" and just to adjust the tracking a bit until it engaged the non-Hi-Fi audio head. That does seem to work, but it requires messing around with it, and the tracking is slightly off. Also, it just doesn't sound as good.

Basically the problem is that in HiFi sound mode, sound is extremely quiet and only out of the right channel. Totally unusable that way. I can switch it to "normal" audio, but what's the fun in that. I already have the old 9451 that does HiFi ok.

Also, after taking it out of storage, it seems to have developed a control track issue, but that's unrelated to the audio because the audio has been wrong for like 20 years and the control track thing just showed up.

Any ideas?

Thanks

[Deter]

I have a PV-4564 which I recorded a lot of my tapes on. When I found this website in 2007 or 2008. Quickly learned this VCR was not adequate. Upgrade your machine. This thread is about fully repairing AG-1980's which are more than good enough for VHS material.

[vol.2]

I have a PV-4564 which I recorded a lot of my tapes on. When I found this website in 2007 or 2008. Quickly learned this VCR was not adequate. Upgrade your machine. This thread is about fully repairing AG-1980's which are more than good enough for VHS material.

Hi thanks. I am talking about my PV-S4990. It's a SVHS machine somewhat similar to the AG-1980. It's a very good machine. I think the problem is the HiFi video heads.

It's working well now besides the audio. I ran some tapes through last night after cleaning the control head, and the picture came back while playing.

I can make a new thread if you think that's better, but I saw mention of the PV-S4990 in this thread, so I wanted to get your opinion as I was hoping there might be some similarity to the 1980? Perhaps they even share the same Hi-Fi heads?

[johnmeyer]

I own the PV-S4990 and the Hi-Fi audio was awful from about 1998 onward. Two years ago I started looking around and found an ex-Panasonic engineer in Florida who was willing to work on it. I won't post any details here because this is Deter's thread. If he wants to repair it, then he ought to get first crack.

The Hi-Fi audio on my unit was full of static and would sometimes fade in and out. The unit had other issues as well.

I have not yet, even after a year, had a chance to capture a large volume of tapes, so I cannot tell you how good the machine is. The repair guy, who also repairs 1980s said he thought the video was just a clear and stable as the 1980. However, fixing it was a huge chore (massive number of caps and adjustments) so I think he was just showing his pride in his work when he said that.

He most definitely did fix all the problems it had.

While the S4990 might be able to produce an equivalent picture to the 1980 when fed a good tape, what I don't know is how the TBC circuits compare. The TBC circuit in my unit never worked from the day I first got it. Now it does seem to do something but again, I haven't had a chance to feed it some dicey tapes and see what happens.

If you have any interest in this, PM me because I don't want to take this any further in Deter's thread. Also, unlike Deter who has been doing this for a long time, the guy I used in Florida seemed like he was only doing it only as time permitted.