Argalby, Thanks for the update I too finished the video board on my 1980 and I'm very surprised how good the picture looks. I only had one cap I did not have to install while I had the board out a .22 electrolytic. I was able to do the job with a pointy soldering iron and a large halogen light with powerful magnifying glass. Some caps are very small and requires a steady hand and lots of patience and or scotch. I did mine in cap size groups and when I felt like working on it. I have noticed on some tapes I get a little color shifting and think it is somewhere other than the video board because I have had two boards in this machine with same result. Anyone have an idea what / where the caps may be other than the Y/C board to cause color shifting?

I toast your accomplishment! It's very rewarding when it's done and you see the nice picture isn't it? You're right a steady hand helps a lot! I pulled all the aluminum caps on the Y/c board, and later, I tested the ESR and all were sky high! Not sure if these were made back when there were bad batches of electrolytic caps being imported or what.

As far as your color shifting problem, not sure where that would be. If it's just on some tapes I'd suspect the tape, or the original recorder that made the tape. If other tapes play well I'd say the AG-1980 is doing well. However, try running the video output thru composite (BNC) Instead of S-video and see how it is. If it's minor, maybe you can correct it during the dub process with a proc amp. There's many, many min-pots on those boards, you can't adjust them without having the right equipment and hours of time. I freak out when my hot air gun gets near them!

I've got over 4 different VCR's here for dubbing, and an (8x8 switcher so I can quickly switch between them) The AG-1980 gets used for dubs 90% of the time...my favorite "stranded-on-a-desert-island" VCR :) (In that case I guess I might need a gas generator too!)

Encouraging reports!

Before I go and break something, is there a trick to getting the daughter cards off the main board, or is it just remove screws where present and carefully pry them and hope the connectors free up?

It looks like a real bowl of spaghetti inside the case.

Dpalomaki,

Remove visible screws on the main board and the screws in the back around connectors it all comes out together. There are two screws securing the video card to the main board that go through main board and into the video card. After all screws are out you can manage to get enough clearance without removing any more wires/connectors just use care and go slow pulling the main board assembly out of the vcr case. The video card just pops out of the main board connectors with a little force. Good luck and let us know how it goes.

There's small "ears" inside the white plastic connectors that hold the connections to the main board. Use a very small screwdriver to pry apart the connector while you carefully pull the board out. Unfortunately the white plastic connecters are very old, and may crack while you do this.

Yes the plastic can break but what I noticed is that you may get some other connections loose and once you put it together you start having some other problems.....If so, take all the boards out and re-solder the connections on the main board and on the individual smaller boards. All of fleebays need rework regardless of who says what, period. You can get some that are ok but not as good as a rebuilt one. I did two units for myself and changing all caps is expensive, labor intensive and some parts are almost impossible to find (including mouser etc.). I would not pay more than $50 on any unit at any time, because all units need a lot of TLC. I did not see a rebuilt one yet so unless you do it yourself... Do not fall for like new, or looks new or very good condition etc. Look at the year of production, look at the pinch roller (that can be changed too...), look at the display, at the capstan and at the plastic discoloration (inside the unit of course) among other things. There are some caps that go first and you can check those readings and that can also give you an idea of how much it was used. I did not encounter problems with the heads. The units do not go out of alignment unless someone worked on them or a part is faulty. And yes those codes coming up are usually a electronic part problem, not alignment.... I encountered that 05 or 06 or 04 problem when rewinding the tape and reaching the end and was not an alignment problem.
Once rebuilt you will love it. The plastics are very good qualitative, the boards are very good also and you can not strip them unless you do not know what you are doing. I would try to change all electrolytic caps on all boards.

All electrolytics?
That is what, 235 give or take?

Yes, all. Not the tantalum, just the aluminium polar and bi-polar. I think is more than that, the audio cards are loaded. On the power source the ceramics also, but they tend to be still ok.

On the service manual parts list there are about 222 electrolytic caps, 44 of which have surface mount part numbers (ECEV..., a discontinued part number per current Panasonic component literature.)

Many parts, not just caps, include the letters "CH" between the part description and value; e.g., "E. Capacitor CH 16V 47U." and not all SMDs have the CH. What does the "CH" signify?

Don't know what the CH means, but 16v 47uF low ESR SMD caps are very common and easy to find. The part numbers are all discontinued because they have been superseded by a more modern (and hopefully longing lasting) series of capacitors.

http://www.panasonic.com/industrial/...ctrolytic.aspx

More about those polymer caps. They cost a bit more, but don't have any liquid electrolyte to dry up.

http://www.panasonic.com/industrial/...ts/os-con.aspx

In replacing caps I go with what is on the board. I noticed one 47uf cap that is listed as nonpolar and actually is polarized on the main board. After that I stopped checking the schematics, plus there are some variations in the Y/B card schematics. Change one cap at a time. Keep the same values for capacitance and do not go lower in voltage. You probably can not find the exact serial number..... Low Esr is good but sometimes lower does not mean better, but that is another story. As long as the ESR is in the average range is ok. Depends on the voltage, on the size and on the materials of course. You will ahve to check the charts for the SMD caps to see the range.The sad part is that the new caps are mostly made in a country with not optimal quality control. You can still find old stock and some are still very good, some are marginal good or bad. How do you guys explain caps made in Japan and sold from China? I have no ideea. Just my 2 cents.
Do your own research and good luck with the decisions you make.

The badcaps.net web site has some interesting information and a lot of threads, although the focus is mainly on motherboards and other PC gear, including graphics cards.

I've read that one should try to match the original specified ESR in power supplies applications. Going too low might result in increased in-rush current and stress other components beyond the intitial design.

Non-polar may make sense in applications where the signal excursions could exceed the DC bias on the cap. Figuring out where they are means reading and understanding the schematic.

What are the preferred source for caps? Digi-Key, Mouser, Allied, Newark, ...
Preferred brands? Panasoanic, C-D, Nichion, etc.

I would be hesitant to go with E-Bay discount sources - no telling the age or origins with any degree of certainty.

I see Panasonic published a news note related to countries of origin for their electrolytics a while back.

In this day and age I figure most of these caps today are made in China or similar foreign country. I bought the cheapest ones I could find on ebay for the Y/C video card and they are working great no problems at all! In the end they are probably better than the originals in this machine. I'm sure some will disagree and that's fine it works for me.

I source Panasonic caps from Digi-Key. No mysteries there, you get the real stuff. Fake capacitors are a problem believe it or not.

Read some current Panasonic litrature on SMD caps. Bottom line is that heat kills. And ripple current higher than 30% of the cap's rating causes life shortening heat issues. Other life-shortening issues include over voltage, frequest charge/discharge cycles (power on/off cycles), and use of polar where non-polar are indicatd to accommodate occasional reverse voltages (as dueing power on/off transients).

Common caps have a 85C 1000 Hour rating. One step up better caps might be rated 105C 1000 hr. These are guaranteed life.

Now put them in a piece of equipment operating at, say 40C (about 104F), not uncommon inside a case, and the expecte life becomes say 20,000 hours for the lesser, and 90,000 hours for the higher rated. At 8 hours per day that amounts to around 7 and 30 years respectively.

But if the temp is more like 50C (122F, not unexp[ected in a full rack bay w/o special cooling) the life is cut in half.

I believe that the existing EVEC series caps were 85C rated. The existing AG1980s lasted 10+ years with the original caps so using similar replacement should get you another 10 years fromteh caps as a minimum. Pay a few cents more for a 105C rated cap and the caps should last a lot longer (and maybe survive soldering better as well).

However, if going for a higher rated cap be sure to check the physical size. to be sure it fits in the available space.

I have been very satisfied with the flee bay capacitors overall with few exceptions. You can still find some made in Japan, Korea or even Europe and they are of very good quality, even if old stock. The rest of them are made in China. The good ones are not cheap, so its not like you pay few cents more for the good ones. No way. You have to read carefully the description and make sure you get what is in the picture. If you ask a question and you do not get an answer or the feedback is not so good, stay away from that. Some do not know what they sell and you can be very lucky too. Takes a lot of time and research to get everything you need that also matches the values and size. Now it is clear why nobody so far put a kit together... It is time consuming and not rewarding. At the end of the day you will still find someone complaining about something. It takes a lot of time, perseverance and a lot of work if you want to do it.
Good luck.

Yes, I agree. It's a real chore repairing these. I've done several and you can't rush it, one blob of solder in the wrong place, or one misaligned capacitor and you're out of luck. To say nothing of the risk of bumping a nearby tiny smd cap.

While we're on the topic, I ran across what I think is an early design AG-1980. Date code on the machine has a "5" (so I guess either 1995 or 2005?) It's Y/C card is somewhat different, it has about 6 wires that come out and go to a connector under the transport mechanism. It also has some sort of metalized cardboard around the Y/C card. I haven't had this one apart, because it works well, but I'm guessing it's got the same parts inside. Any thoughts?

Must be early production model in 1995 given info herehttp://www.digitalfaq.com/forum/vide...sonic-pro.html

It' s probably a 1995 Panasonic. As long as the heads and mechanics are good it is worth repairing. I saw two variations of the Y/C card. The older ones tend to strip easier, though still very good. They say the newer one is improved. I did not notice any difference in the picture nor in the caps quality.
I am pretty sure that those repairs offered by some people on some sites consist of changing few caps in the power module and a couple caps in the board next to the display. By changing those will help a lot, but I would at least check other caps and you will be amazed how many are out of range or dead and the unit is still working. A lot has to go bad in order to notice major changes in the picture. I would also check the audio modules because I noticed a big difference in the sound once they are rebuilt.
After all is done and over you would not want to sell it.
Good luck.

Thanks! Actually that Y/C card with the wires coming out of it is working well, gives a great picture. The problem is that the color/BW switch on the front of the unit does nothing, always stays in color mode. Switched the front board, then went on a hunt checking connectors, but still with no results. Wondering if this is something a university modified for their own purposes. Compared to other units, there's a few caps bridging connectors on the solder side of the main board, makes me wonder.

There clearly are variation in the Y/C card. Mine is a February 1996 machine based on the serial number. Compared to the images earlier in this thread it has wires coming out from under the metal cover, and the daughter (sub) card does not have the crystal and trimmer on it - it is on the YC card. Also the sub card attachment lead routing is different. The other leads from the are soldered to various points under the back side cover, and there are several components mounted on the back looking a lot like an after thought or slip streamed design change/fix (4 ceramic disc caps and a resistor). It is not a pretty thing.

Yes, that's mine! It is really ugly compared to the newer versions. Thanks for the photo, I thought I had the only one :)

Argalby and Dpalomaki, Do these old style YC cards have the same caps on them as the new style? Since your old card is still working ok are the original caps of better quality than the newer style cards??? The YC card I recapped was the new style year 2000 with many bad SMD caps. I do have a cap kit for these with all (SMD and Electrolytic) caps required for the YC card just haven't had time to list it yet.

just_a_hobby --- I haven't had my "old" Y/c card apart, as far as I can tell it's working okay (other than the bw/color switch isn't working) There's no rhyme or reason why these cards fail. I've had other 1996 ones (metal can type Y/C) and they are still working, and I've had new (circa 2001) ones that have failed. Might be because the previous owner didn't use it much, or maybe used it too much. Not sure what's good to prolong life on the original caps. Maybe they need to get warmed up to live longer?

My '96 no doubt has some bad electrolytic caps. It is a mix of SMD and axial lead, and it shows the "barber pole" noise. Also, the timer board has some bad axial caps as evidence by extremely dim display (almost totally dark). However, I have not had a chance to do comprehensive on-board measurements yet - day job and honey-do lists get in the way. A spot check of a few show some with excessive ESR, and some OK. Looks like over the next week I may have a chance to work up a shopping list of replacement caps. The caps are likely what ever was current Panasonic production at the time.

In the photos the caps look the same as newer boards, and the 1995 copyright FMS shows the same Panasonic part numbers in the parts list. The limited markings on the devices I checked appear match the part number ratings for temp, voltage, and mfd.

A photo of the back side of the Y-C board is attached for your viewing pleasure.

Thanks for those photos. Interesting! Certainly not as compact or tidy as the newer version. It looks like the connector strip on the edge may be the same, so I'm wondering how they got rid of all those wires. One of Life's mysteries :)

I saw two different Y/C cards, newer versions (1997 thru 2001) and ALL have bad caps. Just because it works does not mean it works the way it should. Period. If you already have it opened why not check them out. I have one unit like new from 2001 with very low hours and even that had BAD dried caps. The smd are the first to go and even with 10-20 bad caps was still working. Go figure that.
Do not buy into those stories selling units like new, or from a doctor, or low hours of use, etc. Those are sales people. All units need to be recapped.
There are some notorious caps that fail and have big a impact on the unit.
Changing those will cost you probably 200-365 on fleebay, not bad for 10-15 caps.
There are no other parts available for this units at this time because they do not make them anymore, besides a pinch roller or some plastic gear, old stock.
Start with fixing the power module, than fix the Y/C module and if you care about sound look into the sound modules. There is another module that can give you problems once TBC is engaged and you might want to look into that too. The main board is so-so. In the end if you want to fix the display too ( by changing few caps) because by doing that you will get rid of the hissing sound from the power source also.
ALL units need to be recapped, no exceptions or I could not find one. Some will work as is for a while but sooner than later will start act funny...
Just my 2 cents.

Another view of the '96 vintage YC board, under the shield. Note the blue jumper soldered to two pins of an IC on a small daughter card, and a similarly soldered black wire to an IC on the other side of the daughter card. This sure looks like a kludge design fix. There 14 SMD e-caps and 3 conventional e-caps under the cover. I suspect the flexible shield was also retrofit so solve some problem.

Thanks for that view dpalomaki, I haven't had time to compare the two versions of the board, but I'm guessing they reworked the new board to make it neater. Those wires are ridonculous!

On a different note I remember the admin was mentioning that more people are complaining about this units going out of alignment. I can confirm that. Well the plastic components start to show aging signs. First the lubricant locks the plastic gear and when you take them apart you can see hairline cracks. I am not sure if during the years some lubricated the plastics with the wrong lubricant and that caused them to deteriorate further. Anyways the black lubricant that was used between the plastic and metal parts is a problem after so many years. That locks so many times the pinch roller. I would clean up all that and replace it with one friendly for plastics. Yes you have to take everything apart and put it back together, but you have here the manual for the k-mechanism and it was not such a big deal.
Example: I noticed one time that the unit was working great but at times was showing different errors ( not always the same one) and making that funny sound that makes you think is out of alignment. Well I took it apart for at least 10 times and took me more than a month to figure it out. Well it was the small plastic bolt that is attached to the motor (metal part) that had a hairline crack and from time to time was slipping. So the motor was working but not engaging the plastic gear. Simple as that but could not be fixed. What a shame. No parts for that. I can try to get a used unit and hope that this part is still ok. That is why i would not pay more than $40 on a non-working unit.
Still love my panasonic.

Have finally started on the E-cap replacement project.

After replacing about 38 or so radials on six different boards, I am finding about 20% clearly have excessive ESR using an in-circuit tester.

Have not yet started on the boards with surface mounts.

Nice. More than a hundred to go. You will have a great unit. Unfortunately the plastic mechanism can also go bad. Also remove all that dark grease that can make it get stuck and put something good for metal and plastic. So far I had in my hands three brand new units from my friends asking me to take a look, and the same caps that usually go bad were already dry though all the units worked great (picture, display, no hissing noise, etc.) The caps were not completely gone, but with an ESR of 20-50 and only one or two were completely dead. Yes everything was working nice, go figure. This units were just sitting packed nice and not used. Hard to believe, but that is what I encountered but some might have had different experiences. I do this for fun and unfortunately many things you will have to figure out by yourself. I usually do not get straight answer at any of my questions. Wonder why. Anyways be careful when you put it together, some connections can get loose and VCR starts acting funny or even worse. Wish you good luck and be safe.

Analog video is chaos -- it really is. It's not uncommon for several professionals to get together to brainstorm an issue, as we have no idea WTF is wrong either. There's just so many variables.

Another problem is so few video professionals with experience post online. I help where I can, but I certainly don't know everything. And my experience/background is relegated to specific areas of video. I lament this myself. I'm the kind of person that likes to learn from the success and failures of others -- not just myself. So having to go it alone can really suck, especially if other out there have already been there before, and could have saved me the time/pain/nuisance. It's why this forum exists. We do attract some pros and serious hobbyists, and we value them here. I sometime learn from folks here just as much as they learn from me.

FYI, we never purposely overlook questions on this site, even if to say "I don't know". But some slip through the cracks at times. Just bump it if it's sits for a week. One of us will get to it -- probably me if it's an advanced restoration topic.

I have a Panasonic AG-5710 and the picture looks pretty good to me. However, when TBC is enabled the picture scrolls horizontally about 4-5 times per second. Would replacing capacitors fix this issue possibly?


Thanks!

Matt

That's a typical 5710/1980 caps issue, yes.

For myself I would do the following:
1. first the caps on the Y/C card should be replaced
2. have someone check all connections between the main board and the detachable cards. If you attempted to remove stuff or some "professional" did, than you have a loose connection somewhere.
3. someone will have to replace some more caps (check the service manual they have it here and the circuits involving the TBC).
See if someone can help you and be safe.

Do you know where I can get a pretty clean copy of the Panasonic AG-5710 service manual? I have a copy of the AG-1980 service manual. I've seen it some places where you have to pay, which I don't have a problem with if it's reasonable.

This VCR looks like it was treated pretty well. It's very clean. However the guy that shipped it to me did a very poor packing job and left the power cable connected so I ended up having to repair the power supply when it got bumped. It works great now except for the TBC. I'm wondering if something else got jarred inside.

The AG-5710 shares the same internals as the AG-1980. Besides the lack of a tuner and the RS-232 editing interface, it should have the same boards inside of it.

Many professionsal will not provide answers for free - getting paid for answers after all their living.
And many do not want to continue work after the end of the work day.

Hobbiests will often provide answers, but it becomes a crap shoot as to the quality of the answer and the expertice of the responder in the area of the question.
And some things, like analog VCR repair, are a rather narrow field. Many web surfers can't even reset a VCR clock (present company excluded of course).
And of course there are production variations within a given model - consider the changes in the AG-1980 Y/C board documented in this thread for example.

Caps that have aged (values drifted) out of spec might not cause a system to fail or result noticeable image/audio problems. It depends on the specific purpose of the capacitor in the circuit, how far it is out of spec, and the extent to which it was "over designed."