barber poling issues with AG-1980

[mxblitz]

I just bought a used Panasonic AG-1980 off Ebay and it has some issues. The main one being a barber poling effect when playing back video. These are slanted bars that move to the right and show up as distorted chroma. I was wondering if anyone has seen this before and if so what I can do to fix it. I found a similar post on here from earlier this year:
https://forum.videohelp.com/topic362488.html

but his chroma bars were zig zaging and mine aren't.

I don't believe it is a line noise issue (I've got another VCR that doesn't have this problem).

Given the age of this unit and the fact that it is poorly ventilated, I suspect failing electrolytic capacitors are allowing noise to get through. I removed the power supply and did a visual examination of it. I didn't see any bulging capacitors but I guess they could have dried up. Unfortunately, I don't have access to an oscilloscope to check it out and I'd rather not start replacing capacitors unless I know that is the cause of the problem. Other things I suspect are:
- Chroma Circuitry
- Comb Filter?
- Dirty Heads
- Other source of interference

Oh yeah, other less important issues include:
- Flakey svideo
- Display on front is extremely dim

Anyone got any suggestions?

Thanks,
Neil

[moxiecat]

I don't have any technical advice, but as a frequent purchaser of electronics on eBay, my advice is to check the listing. If you were supposed to receive an AG-1980 in good working condition (or if these issues were not listed in the ad), you should contact your seller and let him know right away.

I've purchased units on eBay that have arrived with numerous technical problems. Sometimes the seller is perfectly agreeable to a return, while others refuse to even answer your e-mails (even when you send them a technician's repair estimate for $300 as proof the machine is defective!). If you paid via PayPal, you are usually covered for a return--as long as the timeframe hasn't run out (be careful).

There are usually tons of AG-1980s on eBay. Don't wind up paying for an expensive repair on a unit that was a "good deal."

[Des]

I am certainly no expert, but in my experience I have seen this a few times with other units and it has turned out to be that the barber polling is caused by noise from the video head creating the effect on the TV/CRT. Especially if the unit is above or below the TV.
Simply moving the VCR further away corrected the problem. In all 3 situations that I encountered the actual recording was never affected it was simply a display annomaly.

Don't know if this experience is usefull, but I hope it can be of some help.

--dES

[mxblitz]

I went ahead and sent an e-mail to the seller last night asking if they would take it back.

I tried moving it around and it didn't seem to make any difference. I've got connected to my computer now (through an ADVC-110) and I still see it (I've got an LCD monitor).

I really like this VCR; blows the doors off a 15 year old 4 head Sharp VCR I've got.

Thanks,
Neil

[victoriabears]

I have sold and bought on ebay hundreds of times.

I sold a VCR that worked perfectly, I KNOW the buyer heavy handidly shoved a dodgy cassette into the damn thing and then told me it was not working.

He reported this 5 days after arrival and registered a PAYPAL dispute, they reversed the payment without a by your leave, and would not listen to my arguments, I still have the VCR with a broken transport mechanism that the buyer returned.

[moxiecat]

Sometimes eBay buyers are deceptive. But sometimes, eBay sellers are deceptive too. It DOES work both ways, you know.

For example, I recently purchased a "perfectly working" Hi8 Sony VCR from an eBay seller. It arrived and I hooked it up. The playback picture was extremely dark, even after I tried every type of adjustment--something was obviously wrong with it. I took it to my local repair shop, and they diagnosed some type of RF adapter problem that would cost $300 to fix (I don't remember exactly what). I e-mailed the seller immediately just to ask him how he wanted to handle the problem, and he refused to respond to my e-mails. I had no choice except to file a dispute with PayPal. He got his unit back and I got my money back.

I have a hard time seeing how I was in the wrong in this situation, but obviously, the assumption is that I, as the buyer, was lying. So what should I have done? I did nothing wrong except plug in the unit and try to play a Hi8 tape. I didn't jam the wrong tape in it. The unit this seller sold to me was defective, pure and simple. The poster with the AG-1980 problem above could have the same problem.

Another example: last summer I purchased another "perfect working" Betamax machine. It arrived and while it would load a tape, the play, RW, and FF would not work. Again to the repair shop for an estimate--some type of power supply that needed to be replaced. $250. In that instance, I sucked it up and paid for the repair because I wanted to keep the machine. But I shouldn't have had to, for a Betamax that was advertised as working perfectly.

I realize that sellers are tense about this issue. Victoriabears' post is 100% stereotypical of complaints that sellers write on the eBay forums. But to always think the buyer is lying is absolutely wrong and is seriously irritating to legitimate buyers like myself. When I receive defective merchandise, especially a unit I've paid hundreds of dollars for, I expect a seller to at least respond to my e-mails.

[mxblitz]

I don't think the seller intended to be deceptive. He is an ebay power seller with >99% feedback. To be honest the first time I used it I though it was just the tape... until I tried the same tape in another VCR. Several other tapes recorded on different sources showed the same problem. Also the seller doesn't appear to specialize in VCRs so they probably only did very basic testing.

The seller (in the same listing) said both the following:
"All the features and functions work like they should."
"It is sold "as-is" but I will guarantee no DOA"

Here is a link to the item:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=350209782700&ssPageName=ADME:X:AAQ:US:1123

[moxiecat]

Hmmm....well, that's a little different because he doesn't claim the item is perfect, just that it won't be DOA.

I would take this listing to mean that the item's basic functions work such as play, eject, FF, etc.--BUT that there may be some smaller problems with the unit that the seller either doesn't know about or can't diagnose. And if so, they may be your problems because he does say he's selling it "as is."

I would pursue e-mail contact with the seller and tell him about the problem, but in the end, he may not be able to help (nor should he be held responsible, IMO). In that case, you will have to decide if you want the VCR diagnosed/repaired to your satisfaction.

[victoriabears]

I have sold many items with no problem, and agree that there are bad sellers and buyers, i was recounting a specific experience, more to help the 1980 buyer so he knows he only has to file a dispute with paypal to get his money back.

[lordsmurf]

I'd still suggest power-related issues.

[themaster1]

random thoughts:

what about "poor grounding" ?

Open the case of the vcr and inspect for burns on the eletronics or something that look out of normal. (it's summertime it's getting very HOT in those old babies!) I know on mine it is hence the fact i run it at night only.

A good cleaning of the heads is welcome and don't forget the dust on the electronics with compressed air

Test all the outputs: scart , s-video

[mxblitz]

Yeah if he won't take it back I'll probably just try to fix it myself.

I've got a degree in Computer Engineering so I know how a lot of the individual components work, particularly those used in power supplies and I've still got my soldering iron from college. However, theory isn't the same as application, and I've never actually tried to repair something like this before.

These VCRs use switched-mode power supplies right? I may take the PSU to work and see if we still have an oscilloscope lying around I can hook it up to. Not sure how meaningful that will be though without putting a load on it.

I'll look more closely at it tonight and look for grounding problems. I didn't notice anything out of the ordinary on the PSU but I didn't look anywhere else.

I'm not familiar with 'scart'. I looked it up on google and found what the cable looks like and I didn't see anything like that on this VCR.

I did try the coax and it doesn't appear as bad there but it is still visible. I don't have anything to connect to the BNC connectors. Does this VCR not have an RCA video output?

From the research I've done about cleaning heads, it sounds like I need 99% isopropyl alcohol, and some kind of foam applicator that won't leave lint behind. Any idea where I can get the 99% variety locally?

[lordsmurf]

SCART isn't on NTSC equipment. The poster who suggested it was from Europe. Disregard.

"RCA video output" = no such thing.
I think you mean "composite". The AG-1980P has BNC connectors. You need adapters to use it as composite.

[mxblitz]

Oops your right. At the time, my mind drew a blank and couldn't remember the correct name for it.

The seller responded to my e-mail and said that it wasn't doing this prior to shipment and that they would honor their no DOA policy. They also said if I want, they would send me a partial refund if I want to try to get it fixed myself. I am quite surprised how nice they are being about this. I told them since it wasn't doing it before they shipped it to me, I'm going to take a UPS home from work and hook the VCR up to it to rule out any AC line noise issues.

Thanks,
Neil

[moxiecat]

Wow, nice seller! One to remember.

You could also have a video repair shop look at it to see if they can diagnose a problem. Then you would get a formal estimate for your seller, for the repair cost.

I'm very impressed your seller would send a partial refund; that's what I asked for from the seller I mentioned above. I even gave him the repair shop's estimate. He refused to give any refund for the repair or accept a return. He could have paid $200 for the repair and kept the difference. Because he decided to be a jerk and not even answer my e-mails, he got the broken unit back and had to pay back the whole $400. Which is where we started to begin with, but he COULD have made a profit on a broken machine if he would have been a little nicer!

Again, this is definitely not all sellers--I've had a lot of excellent ones as well. But the response you got here is really impressive to me, having gone through the experience I did!

[orsetto]

It is hard to diagnose without actually seeing your AG1980 on your TV display, but some degree of weirdness is kind of inherent to the AG1980 design: its a one-of-a-kind model, subject to overpraising, and its defects often get swept under the rug.

Diagonal lines or chroma herringbone, if isolated to certain parts of the image but not the entire image, are usually due to mistracking of the AG1980's digital noise reduction circuit. This circuit is very effective, but often hyperactive, and it cannot be switched off, meaning certain tapes will simply be ill-suited for playback on the AG1980. Both the JVC and Panasonic high-end designs have flaws, which is why many of us try to keep both on hand. The tape that plays badly barberpoled on the 1980 will often play reasonably well on the JVC, while a tape that jitters maniacally on the JVC will play rock-steady on the Panasonic. Neither is perfect for all tapes at all times, you have to choose the least offensive compromise.

A little-known issue with AG-series Panasonics is their sensitivity to grounding: if you are seeing a barberpole or herringbone pattern that rolls slowly across the entire image, you may be having this problem. I pulled my hair out over that issue for a year before desperation inspired me to try one of those dinky plug adapters that converts the three-prong 1980 grounded AC plug to two-prong ungrounded. Once I did that, the the problem went away. I think this is referred to as a "ground loop" but I'm not sure, whatever its called, you solve it by breaking the ground connection on the AG1980. I noticed my AG1970 and AG2560 also benefit by disconnecting ground with a plug adapter. For $1.29, its worth a try.

The front panel dimness is a design flaw seen in 9 out of 10 AG series Panasonics that use this particular type of display (AG1960, 1970, 1980 and some others). Brightness of the display is good indicator of how much use the VCR has seen: heavily used AGs have the dimmest displays. The repair shop I brought my units to is owned by very skilled Asians who unfortunately do not communicate very well in English: they were pretty emphatic that the panel dimming is common, but I couldn't make out if they were telling me its related to the power supply or the display panel itself. Unless you're actually using the machine as a VCR in all modes, it isn't worth spending money to "repair" the display panel. My AG1970 panel has been near-unreadable for three years, but the machine works fine otherwise. For transfer work, the only useful info shown on the display panel is the tape counter. If yours is so dim you can't read it, you might consider searching eBay for the AG-A96 edit controller accessory: this is a large, wired remote control with its own very large black-on-grey LCD tape counter display. It can often be bought for $30 or less, a lot cheaper than repairing the display on the VCR. Since one AGA96 can display the tape counter of up to two connected VCRs, and control both of them, its a handy thing to have anyway. The AG-A96 (or previous AG-A95) works with the AG1950, 1960, 1970 and 1980 VCRs.

The "flakey SVHS" connection is another typical glitch with second-hand AG-series Panasonics: despite being excellent SVHS recorders, their BNC composite jacks are more reliable than their S-video sockets. The only cure for a poor S-video connection on these is a trip to the repair shop. Before you spend the money, consider whether the BNC output is an acceptable compromise: to my eyes, S-video output on the Panasonic AGs is not significantly better than the BNC jacks when playing standard VHS tapes. I wouldn't bother with S-jack repairs unless you have a number of true SVHS tapes to transfer.

[mxblitz]

if you are seeing a barberpole or herringbone pattern that rolls slowly across the entire image, you may be having this problem.

This is exactly what I'm seeing. A chroma barberpole pattern that slowly rolls across the entire image. I will definitely try this. The intensity of the pattern also seems to vary. May be related to having certain other appliances on in my house.

Thanks!
Neil

[mxblitz]

Well when I first hooked it up using the plug adapter it looked perfect. Then I tried it without, the plug adapter, still looked great... Tried a few other things and now no matter what I do it has the herringbone pattern. I suspect the problem may be related to heat... as in it only shows up after the VCR has warmed up. This may be why the person selling it didn't notice the problem. I even hooked it up to a UPS and disconnected it from the wall... same thing.

Here a link to some video I captured that shows the problem. Sorry it's so big. I created this using WinDV to capture from my ADVC110.

http://www.mediafire.com/?mmvnxmoihzx

Thanks,
Neil

[themaster1]

That's some nice interferences that we got here, do you enjoy these ?

I say poor grounding or a mix poor grounding + power supply faulty (i'd say dusty)
Dust a.k.a the number 1 killer of electronics and by extend your viewing pleasure. Food for thought, have a nice day i'm out it's late here.

[mxblitz]

Well I'm sending it back. Nothing I tried worked. Next time I'll spend a little more and get one guaranteed to work properly.

Thanks for your help everyone!

[lordsmurf]

Definitely a power line noise issue of some kind -- heat related may be it, absolutely.