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  #1  
12-08-2018, 08:00 PM
Chickensalad39 Chickensalad39 is offline
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I bought a Panasonic AG-1970
After getting a different s video cable I was able to get a picture, after an hour the screen turned black.

I found it seems to be tied to the TBC.

I bought this for the TBC, could some one explain what is wrong.

The first time this happened I cleared the error with rewinding, then after a while I couldn't, worse it does seem to happen after a bit with out the TBC.

Any advice?
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  #2  
12-08-2018, 08:20 PM
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lordsmurf lordsmurf is offline
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Bad caps most likely.

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  #3  
12-08-2018, 08:50 PM
Chickensalad39 Chickensalad39 is offline
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Quote:
Bad caps most likely.
Bad what? Please explain, are you talking capture?
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  #4  
12-08-2018, 09:30 PM
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Bad capacitors.

Search the forum for the phrase "bad caps" or "capacitors", especially posts about Panasonic or AG-1980P (1980, 1970, etc).

This is a common issue with AG1970 and AG1980 decks in the 2010s. Unless a deck has been re-capped, it's almost guaranteed to have issues these days. Probably 99% of decks you see on eBay have these sorts of issues, even the so-called "tested" and "works" units.

JVC is better as a main deck, as those last longer. Save the Panasonics for trouble tapes that hate the JVC.

The only good place to get a AG-1980 is from TGrant or Southern Advantage. There's a reason these decks cost $800 from those places, not the $200 POS special you find on auctions.

The most common tell-tale sign of bad caps is the TBC on/off dims or brightens, or has more serious issues as yours does.

Quote:
Originally Posted by badcaps.net
How did this happen?

The reason this problem exists is because of a large-scale industrial espionage foul-up. Some companies decided to steal an electrolyte formula from another competitor. Little be known to them, the stolen formula was incomplete and flawed. They didn't discover this until it was too late and they had manufactured and distributed literally MILLIONS of these flawed capacitors. It was way too late for any kind of recall, and even today, these crappy components are being used in new boards. As I mentioned before, I believe this problem runs much deeper than simply an industrial espionage screw-up, as that incident was exposed years ago, and the problem still exists today. Nowadays, it just boils down to corporate bean counters cutting corners to save money by using shoddy components.

The cause...

This inferior and flawed electrolyte formula was used by a number of component manufacturers that sold to many different, reputable, and well known motherboard manufacturers. This problem isn't isolated to one particular brand of motherboard, and not even isolated to motherboards alone. I won't mention brands, but a VERY popular monitor manufacturer has been plagued with RMA's on some of their monitors that were built using these inferior capacitors. This problem has been reported in computer motherboards, monitors, televisions, radios, and stereo equipment. Through my experiences owning a service center, I've personally seen and serviced a large number of 'high-end' equipment that had prematurely failed capacitors.

More detailed information...

In more technical terms, this is is what actually happens to the capacitor...in the simplest of terms. Think of an electrolytic capacitors as a battery. They are designed to store a charge and release that charge depending on the specific requirements of the circuit. Inside the capacitor there are two metal plates with dielectric material between them, wrapped in paper, filled with acid (electrolyte), and sealed in its housing or 'canister'. What happens is the flawed electrolyte prematurely deteriorates and dries up. When this happens the capacitance value changes, becomes erratic, and can even short completely, which obviously causes the circuit to malfunction. On your motherboard, this results in system instabilities or complete failure of your board.

From a physical standpoint, the capacitor can display a number of symptoms and even have catastrophic failures. Catastrophic failure is a rare phenomenon, but it does happen. The reason is this... A capacitor canister is completely sealed and air tight. When the electrolyte dries it turns from a liquid state into a gas. This gas expands with heat and builds great pressure inside the canister, the theory is the same as a pressure cooker. Of course the obvious happens when that pressure builds too much, and the capacitor will vent. This is what causes the capacitor to 'bulge' or swell up. In a catastrophic failure, the capacitor may actually burst or explode. It can sound like a firecracker going off or sound similar to air escaping from a car tire, depending on how high the pressure has built. A physically failing capacitor has an ammonia-like odor (at least that what I thought it smelled like)... Capacitors that has swollen up are easy to detect, but one that has burst are even more noticeable. It will usually blow from the top and spew its innards throughout your computer case. The innards are mostly paper and any remaining electrolyte, but it sure can leave a mess... Once again, catastrophic failure is a rare phenomenon... It's not dangerous either, as long as you practice common sense safety precautions! If you suspect bad caps, don't put your face near them while the system is powered up, and don't eat the paper or electrolyte that they blow out!

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  #5  
12-08-2018, 09:49 PM
Chickensalad39 Chickensalad39 is offline
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So the machine got to me, and failed?
It worked for the seller and the person he bought it from and then failed, any chance they could've known or it was the weather during shipping.
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  #6  
12-08-2018, 09:58 PM
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Those Panasonic decks don't suddenly fail. As mentioned, the tell-tale is the TBC on/off. It starts out merely having dimmer or brighter image, obvious difference between on and off. Eventually the board caps exceed tolerances, and what you get is catastrophic issues.

The seller either didn't know much about VCRs, or tried to pull a fast one. Both are likely, 50/50 as to which it is. Either way, it was surely failing for at least 6 months. When the TBC dim/bright issues happen, you have 6 months until total failure.

I've gone through this with about 8 decks myself.

TGrant charges about $375 each for the re-cap job. It's tedious. I'm not sure if Deter does them anymore.

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  #7  
12-08-2018, 09:59 PM
sanlyn sanlyn is offline
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Quote:
Originally Posted by Chickensalad39 View Post
It worked for the seller and the person he bought it from and then failed
What makes you think it wasn't misbehaving for others before your received it? it does sound unusual, though -- the AG-1970 is supposedly more robust than the AG-1980.
Was this an eBay purchase?
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  #8  
12-08-2018, 10:11 PM
Chickensalad39 Chickensalad39 is offline
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Yes it was eBay, and at this point even though I can return it, I don't think it would be reasonable, unless I think he was at fault it's my responsibility, nor can I afford to repair it.

It would have been nice if this sites vcr guide had a note warning that this is a common problem for AG-1970, so people don't make the same mistake as me.
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  #9  
12-08-2018, 10:38 PM
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Just understand it's not junk.
TGrant might pay $100 for it. Contact him, he buys these VCRs.

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  #10  
12-08-2018, 11:53 PM
jwillis84 jwillis84 is offline
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One thing I've learned about buying VCRs on some auction sites is where you buy and where they get delivered matters. A lot.

Different parts of the country have different electrical grids and voltages coming from the outlets. We have "standards" that say 110-120 volts but in truth it varies quite a bit. Where I live its regularly 127 volts.

So buying one from New Jersey and "importing" it to Texas.. if you don't step the voltage back down to 120 or lower.. caps can pop or distort right away.

I'm not talking "surge" protectors, "lightning" protectors or battery backed UPS for "brownouts" or "spikes.." those are important. But, its the high voltage and higher heat situations that can make a difference fast especially with caps. the AG-1970 and AG-1980 came from the early 1990's they are awesome machines but the world has changed and they don't adapt well.. you have to take care of them. (and consider they were "studio" machines, studios often had power conditioners.. not your regular home living room situation)

Tgrant is a fantastic place to do business with, but they are very strict about "pre-approved" work and "shipping" requirements. They really want you to not to have to wait in line behind a lot of work on their bench, and they care both about taking care to box shipments up properly to them (they have guides at their website).. and they do exemplary work packing the fixed unit for its return journey.
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  #11  
12-09-2018, 07:35 AM
Chickensalad39 Chickensalad39 is offline
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Ok so I plugged it in this morning to see if maybe it was just a random incident.
i am now thinking it was random that it worked.

When I first got it the s video supplied with it didn't work.
Then I tried a different s video cable.
It worked then had the problem.

Now it neither gives a signal, nor do
I get any audio output.

I am going to contact the seller.
Out side of that I think I will contact TGrant and see if they want it to repair and sell, at this point I don't think it's worth the trouble and stress.
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  #12  
12-09-2018, 09:04 AM
dpalomaki dpalomaki is offline
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Electrolytic capacitors can fail or change value over time, especially if the system is not powered up for a long time. The AG1980 was especially prone to this due to the use of surface mounted AL electrolytics that were manufactured with a defective electrolyte. It typically took on the order of 10-15 years for the problem to arise with the VCRs. Darkening display and "barber pole" like color image interference on output were common early symptoms. There was a rash of similar problem with other gear, especially PC motherboards and some expansion cards. (That is part of why we still see motherboard ads speaking to the type capacitors they use.) There is an interesting story about industrial espionage gone awry - stealing only part of the good formula - involved with this issue.

The AG1970 dates from an slightly earlier time when surface mounted electrolytics were less common, and thus they they tended to be less prone, but not immune, to capacitor problems.

Does it still handle tape (FF, REW Play)?
Does the display light showing mode, time, etc?
Do the VU meter bars show audio?
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  #13  
12-09-2018, 09:16 AM
Chickensalad39 Chickensalad39 is offline
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Mechanically it still works, I just don't get any video and now apparently Audio.
The displays work, it plays, the meters show audio, it's just that each use has been rather random.
I expected audio at least since that was what I was getting when I unplugged it last night.
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  #14  
12-09-2018, 11:43 AM
dpalomaki dpalomaki is offline
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Does the Audio Out button have any effect?
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  #15  
12-09-2018, 12:26 PM
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You know, what often happens is this:

A person that is new to video capture/conversion (like yourself) hits up Google for information, and (hopefully) comes across a site like this, and (again, hopefully) reads posts from somebody like myself. I talk about the virtues of the Panasonic and JVC S-VHS decks, show comparison samples of just how superior the equipment is to a plain old nasty VCR. You might even post questions/concerns, and get responses that confirm its the thing to get.

But then you make the mistake of running to eBay, which is often a VCR dumping ground. Sellers there most often have no idea what they're selling, no clue how to truly test it, no understanding as to how it should and should not work. As I often state, at least 2/3rds of all eBay VCRs are obviously damaged, while at least half of the remaining so-called "working" and "tested" units are also flawed in some way. That leaves a narrow window of about 15% of all VCR sold on eBay might be decent, maybe -- but those are also going to be the ones that cost $$$. Sometimes asking more than true value.

When dealing with known-problematic decks like Panasonic, it's less than 15%, and sometimes 0%.

Sometimes, the person simply thinks we've all been giving bad advice, rather than understand they simply bought lemon. Because when the gear works as it should, what we're saying about it is accurate.

So it's important to also seek advice on where to buy the gear, not just what to get.

Just FYI, at the moment, I have a few JVC decks available, in the marketplace forum, and each is extremely reasonably priced given the condition (cleaned, well-maintained, refurb'd as needed) and thorough testing/vetting done. And I do have a few decks with A+ tracking on EP tests.

Or if you still want Panasonic, go to TGrant. That's where Site Staff buy or get their decks repaired, as well as many others here. (I think member Quasipal helps with PAL decks, maybe does some repairs. Also www.VCRShop.nl in the Netherlands.)

@dpalomaki, do you also repair NTSC Panasonics?

We need to give some attention to the Where to Buy / Fix VCRs thread. One of the core philosophies for this site is making sure the equipment needed (to do everything discussed here) is available. It's why I make some things available here, instead of selling elsewhere, and why we put together some of these forum stickies.

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12-09-2018, 03:07 PM
Chickensalad39 Chickensalad39 is offline
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Okay first off I was able to get audio and a signal when the Tbc is off.
Second the seller is fine with a return if I find it's defective.
Third, I am back to having the picture when the TBC is turned off.
If I fast forward with TBC ON I get a grayish flickering
The audio out selector still works.

As it stands I'm toying with either just returning it or waiting till I can save up to have it repaired, as it stands I am checking to see if maybe, just maybe it could be the capture card, I use a Diamond VC500, I know it's cheap but for what I needed it for in the past it was fine.

I'm going to test the input on my TV, I've had some interesting problems with the capture card before.

Also just so it's understood, all my tapes are in SLP, just in case it's relevant.

That's the only reason I took a risk on the Panasonic, other wise I was tempted to wait for a JVC.

-- update --

I've decide to return to seller, I will wait a while and buy from TGrant next time.
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12-09-2018, 09:22 PM
dpalomaki dpalomaki is offline
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Quote:
@dpalomaki, do you also repair NTSC Panasonics?
Not as a business or for others, essentially only for my self. And with advancing years it becomes more difficult to do fine work like some circuit boards require.

Testing the VCR by direct feeding a TV set is a good idea. Try both TBC ON and OFF. While TV sets are very forgiving of out-of-spec signals it can give an idea what the VCR is doing. Capture cards are often unforgiving of poor signals, but I cannot speak to your cared. And I've seen some cases in which a tape will capture better with the TBC off.

Working with the TBC off argues for something wrong on the TBC board, which could be simple or complicated. Loosing both sound and video totally is a bit odd.

About the only way to buy a VCR from ebay or any auction really or even thrift shops, flea markets, and garage sales is if you can give the unit a try with some sample tapes, and that only works if you know what you are looking at.
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  #18  
12-13-2018, 11:35 AM
Chickensalad39 Chickensalad39 is offline
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I got a replay from the seller upon returning.
It works for him, yet I can't figure out what I could've done wrong.
I tested both capture card and TV.

The TV registered a signal, but it was completely black when TBC was on.
I know when I first tried to use it the same thing happened and thought it was the cables, I tried a different cable and it worked, then it went out.

Are S video cables extremely sensitive, I find it hard to believe that I was plugging them in wrong and got lucky once.

And if they were plugged in wrong, why did it work when the tbc was on, was every tape I tried giving some sort of error that set things to black?

What could I have done wrong.
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  #19  
12-13-2018, 11:49 AM
hodgey hodgey is offline
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S-Video cables can be sensitive, though what I've usually had happen is that the colour channel can some times fall out if they're not plugged in well. It's a good idea to test with composite as well if there's an issue.

Maybe it's a loose solder joint or something that has lost or gained contact from moving the machine around. Alternatively, if it's a capacitor issue, they can be affected by all sorts of environmental conditions, like temperature, or just not being plugged in for a while.
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  #20  
12-13-2018, 03:45 PM
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Cables are an issue, as is solder joint.

Yes, caps are a pain. Temperature, elevation, geography, it's all a factor. When I was forced to move, almost 1000 miles south, due to do health, most of my Panasonic gear developed issues right away. It didn't like the change. Had the caps been new, it wouldn't have been an issue. But with the caps badly aged, it affected them.

These are all plausible, and I've seen many such things in the past 25+ years of serious VCR usage.

I throw at least 1 pair of s-video cables in the trash every year. The cables age. Sometimes new cables are garbage, either returned (if bought) or trashed (if free, usually coming with a device).

The other option is the seller is lying. If eBay, that happens too often. I still remember the joke on The Big Bang Theory, where Penny threw an iPod on the street, smashing it, and Raj retrieves it. The group asks why he did that, and his response was to list it on eBay as "slightly used".

Or the seller doesn't know what he's talking about -- ie, not a video person, just a goober with VCRs, usually a recycler, or a Storage War wannabe.

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