Electronics Repair Question

[LauAnn]

I have a Panasonic (DMR-E85H) DVD Video Recorder that appears to be getting no power -- i.e. it won't turn on.

A few years ago I replaced the C1270 and C1271 capacitors in the unit to fix a 'Please Wait' message that wouldn'g go away. But this problem is different. There is no display or error message and no indication the unit is getting power.

Some sources on the web indicate it might be two other capacitors are now the problem (1260 and 1261). However, before I tear the unit apart to check to see if they are blown, I want to make sure it's not a fuse issue, as others have suggested they've done. The problem is I don't know how to do that and can't find a good 'how to' that walks me through it.

I'm assuming they are talking about a fuse in the unit? If so, how do I go about finding the fuse and then checking to see if it's still intact?

Thanks for any direction.

 

[LauAnn]

I did find the following information -- The Panasonic power supply is located close to the AC cord connection on the rear panel. Be sure to check the nearby fuse if your Panasonic is dead. If the fuse has blown it is inexpensive and easy to replace. If a power supply capacitor has failed the Panasonic may be dead for that reason as well.

Capacitors store an electronic charge. That is reason enough to disconnect the AC cord well in advance of the procedure to allow the capacitor to lose its charge. Exercise caution when working in and around the power supply, even after the power has been disconnected.

If the Panasonic is operational but experiencing problems it is likely that one or more power supply capacitors are beginning to fail. The power supply will have electrolytic capacitors (a canister) and “chubby disc” type capacitors (a smaller device standing on two legs). Electrolytic capacitors are black or dark brown jacketed canisters with an aluminum top and a grey stripe running down one side. The grey stripe indicates the capacitor's polarity. The leakage may appear as bubbly ooze on the capacitor’s side or around the capacitor's base and on the circuit board. This leakage will probably be somewhat hardened rather than pliable or moist. “Chubby disc” type capacitors may be beige or brown. These demonstrate impending problems with bloating or leakage.

 

[BigMoneyJim]

The fuses I've seen inside consumer electronics usually look exactly like car fuses, the kind that are glass tubes with metal caps on each end and the fusible filament running down the middle, perhaps a coil or perhaps just a thin flat piece of metal.

The fuses are generally close to or on the power supply. In a couple of cases where the power supplies were modular plug-in metal boxes, sometimes you have to open up the metal box to see the fuse.

However, often a blown fuse is an indicator of a problem elsewhere, and the replacement blows immediately.

Also, yes, the capacitors store electricity and in some devices the stored energy can be enough to kill you.

I used to dink around with old electronics, but a few words: Craigslist, pawn shops, eBay, Slickdeals.net, local retail store w/cheap consumer electronics.

 

[LauAnn]

Thanks. I replaced the blown capcitors (the fuse was fine) and the unit has powered back up. But it now appears the hard drive is kaput and consequently the dvd player portion won't work either. The unit is 10 years old and this particularly model has a history of issues so I'm not willing to have it professionally serrviced for $100+. I think I'm going to retire it and move on.

 

[TromboneAl]

Interesting, I had the same unit and replaced the caps to fix the Please Wait problem. I recommend upgrading to a TiVo -- it is significantly better. I actually still have the E85H and power it up when I need to get something from the TiVo or Internet onto a DVD.

 

[LauAnn]

I wasn't quite ready to give up and found an article on the internet where the user forgot to plug the power supply to the hard drive back in when he reassembed the unit after replacing the capacitors. Tuns out I did the same thing! I am now back in business. Eureka!

 

[Nords]

I wasn't quite ready to give up and found an article on the internet where the user forgot to plug the power supply to the hard drive back in when he reassembed the unit after replacing the capacitors. Tuns out I did the same thing! I am now back in business. Eureka!

It takes a lot of guts to admit an "oops" like that on a discussion board. Thanks.

If a submariner did that we'd be sitting through incident critiques for another two days... "What do you mean, you followed the procedure?"

 

[TromboneAl]

I wasn't quite ready to give up and found an article on the internet where the user forgot to plug the power supply to the hard drive back in when he reassembed the unit after replacing the capacitors. Tuns out I did the same thing! I am now back in business. Eureka!

It's even more fun to get something working after you thought you'd failed. Congrats.

 

[omni550]

I wasn't quite ready to give up and found an article on the internet where the user forgot to plug the power supply to the hard drive back in when he reassembed the unit after replacing the capacitors. Tuns out I did the same thing! I am now back in business. Eureka!

LauAnn,

Persistence pays off! Congrats on getting the unit working again.

omni

 

[Gumby]

It takes a lot of guts to admit an "oops" like that on a discussion board. Thanks.

If a submariner did that we'd be sitting through incident critiques for another two days... "What do you mean, you followed the procedure?"

As I recall, when some piece of equipment did not start up, the troubleshooting routine on the boat went something like this:

1. Is the ON/OFF switch in the ON position?
2. Is the power supply breaker shut?
3. Is the power supply bus energized?
4. Are the inlet and outlet valves open?
5. Is there any (water/oil/etc.) in the supply tank?
6. Are the interlocks cleared?

It was astounding how many things cleared up by step 1 or 2.


Anyway, congratulations LauAnn. There are few better feelings than persisting in an electronics project and having it finally work properly. Most people would not even try.

 

[TromboneAl]

Sattlinger's law: it works better if you turn it on.

 

[ls99]

In my days of techie w*rk in NY.

Is Con Edison working today?

 

[ERD50]

I wasn't quite ready to give up .... I am now back in business. Eureka!

Congrats. When I read about you changing caps out and such, I really didn't think a dead disk drive was going to stop you! Drives can be recovered from old computers and such, but even better you found the problem - good job.

So many products are so hard to take apart, and even harder to get back together. I almost always take a stab at fixing them, but my success rate isn't too good. But I figure I have nothing to lose (assuming I don't hurt myself in the process - the main danger is cutting/stabbing myself trying to open up some of these things!), and the geek in me always likes to see what's inside. Sometimes I strip out a few parts that I think I may use for some other project (but almost never do).

When I do manage to fix something, the satisfaction is not so much pure $, but knowing I kept something out of a landfill a bit longer, delayed the environmental impact of replacing it, and when I do replace it, the replacement will probably be better/cheaper at that point.

-ERD50