Panasonic DMR-EX75EB - U81 issue.

[Turnip]

Hi folks,

Have one in displaying U81 - Had a look for duff caps under the centre board and found bulging C4056(470/16) and C1538(100/25) - Replaced - Still U81.

Wonder if there's any other likely causes ? - Thanks - Chris

[astracat]

hi turnip
u81 is a communication error with microprocessor try pressing power for more than 5 secs then reboot also check connections on uart processor
regards
astracat

[jordan]

Error code U81-posiblty
C-1530 (100uF/25V)
C-1533 (680uF/6,3V)
SMD IC-1508 (MD-5001T)

[downunder]

Hi Chris,
If those caps were bulged. there's a good chance that IC1508 (Pana p/n CODAAJG0001) on the underside of the PCB will be faulty. It's an 8 pin DIL surface mount and supplies 1V8 to the Backend Module between HDD and DVD. You may see a tiny pinhole in one corner of the IC. Normal p/n for IC is MD5001.

I've also had the Backend Module cause it and on occasions have had to replace the entire board under the HDD in desperation.

Bruce

[Turnip]

Hi folks, and many thanks,

Guess might hopefully be IC1508(MD5001T) although it looks pristine.

With back-end module out of the way might check any 1.8 voltage. Noticed C1533(680/6.3) had been replaced a while ago, by a chap who managed chew up the print a bit, just now need a S/M so can check voltages from the top.

Also noticed on line that an enthusiastic amateur did the whole job with the chip/caps change in half an hour, and suspects the next would take only 15 minutes - Bit impressed by Yoof - Chris.

[downunder]

 Hi Chris,

Service manual attached.                 Bruce

[Turnip]

Thanks Bruce,

Customer only here for a weeks holiday so collected un-repaired. Had some doubts as to a simple job as caps  C4056(470/16) and C1538(100/25) seem remote from IC1508, might even be a power board problem as guess excess voltage/ripple maybe.

Will have a spare chip for next time though -  Chris.

[downunder]

Hi Chris,

Please explain. Who takes a clunky DVD recorder with him on holidays? Or perchance it was a local yokel on a driving holiday?

Bruce

[Turnip]

Hi Bruce,

It's a thought but guess some folks do - Recall chap brought a 22" CRT Sony down from Scotland on holiday, dropped it in as it didn't quite go.

You will have guessed it was those horrid Sony Tact switches, but not having met the problem before changed some rather expensive chips for about 80 Quid, and naturally it still didn't go.

Not an earner that time, but those Sony Tact buttons made the pound over the years.

Reminds me of the Sanyo VTC5000 VCR where the mains fuse popped, and some knowing chap said it was due to the secondary PS chip, so bought a dozen and used every one where the mains fuse had blown due to inadequate rating - Folks were happy with job done, as had value for money.

Tend to have a 'No costly crap on the shelf' attitude these days, as when things went LCD wept as chucked at least a hundred new replacement  RCUs and Lopts into the skip, due to not thinking ahead - Chris.

[downunder]

Hi Chris,

Methinks most of us are guilty of such folly. To my regret, I dumped boxes of valves, service manuals and turntable gear. Old technology. Never use any of them again. Now people are making a killing on eBay with such stuff. How was one to know that vinyl and valve audio would have a renaissance.

Bruce

[Turnip]

Hi Bruce,

It's a thought as a customer of mine has been buying Aiwa gear from Ebay, have had at least five recently for belt replacement.

Later Aiwa used square belts, where can get away with most anything as they stretch a bit, but the earlier flat belts are a bit serious.

Note a chap on Ebay has recently sorted China to re- produce flat belts for some Aiwa at ten pounds a pop. Did one, an Aiwa AD-WX707K dual cassette with two ten pound belts.

Not an earner, as had used what I had, maybe three times, so natch' FOC - Chris.

[Turnip]

Hi Bruce,

Just had a Panasonic DMR-EZ27EB in for no DVB where the caps sorted it. Sadly it had no HDD so couldn't swap it for customers machine.

Do quite a lot of VCR cassette to DVD stuff, as makes the pound. Folks are now bringing in stuff recorded in a format where folks gallop across the screen and my old LG combi can't suss it.

Normally go to Ebay, buy DVD and re-record it - Difficult with home movies though.

Off to a Car Boot for something modern - Chris.

[downunder]

Greetings Chris,

The same loss of DVB occurs in the DMR-EX75/85 with the failure of C1553 which was changed in your previous machine.

I steer clear of folks that want stuff recorded, as well as car boots. There are punters about who make a livelihood from dubbing such things as Greek weddings.

Bruce

[Turnip]

Hi Bruce,

Shop partner turned up with Sony and Panasonic VCRs that folks had donated to his bin. Seems some modern stuff can sort incredible long play recordings where my LG combi fails.

Make the pound with such stuff - Sometimes get the original DVDs from the Flea and just copy them,
Folks maybe confused by menu - Never a word though.

First three sorted, just have one where folks recorded family in 'Ultra Slow'

Guess Sony / Panasonic will hopefully sort where LG doesn't  - Chris.