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[tonyappuk]

I have recently repaired a Panasonic PVR with DVD writer (I forget the model number) It wasn't very old but out of guarantee. The symptom was a failure of the built in Freeview receiver. Internet searches revealed the same sort of electrolytic failure this time of a 670 microF and 100 microF in the power supply. Replacement of these blown (literally) components fixed it. I wonder if quality control of either components or equipment has slipped even further these days. Very disappointing for and old telemender.
Tony

[oldfogy]

I wonder if quality control of either components or equipment has slipped even further these days.

No, never.

This is the new thing that is now coming to light which is called 'Built-in obsolescence'
Where as as most people would then either claim on the extended warranty or simply buy a new one.

[HPsauce]

Blown elecrolytic capacitors is a common theme in all sorts of "newer" (mostly post-2000) equipment.

Luckily I have a neighbour who is an electronics designer and "breadboards" a lot of stuff in his home workshop so has a huge stock of bits.
So if something misbehaves or packs up that could in any way be due to this issue I open it up, look for bulging caps and source spares from my "handy local supplier". Saved a fortune that way over the years. 

[sevenlayermuddle]

I've rescued quite a number of 'failed' devices from faulty capacitors of late, a couple of PSUs and a netgear ethernet switch.   

There's a few important factors to consider when choosing replacements..

1) The life expectancy of electrolytic caps at rated temperature is often unbelievably short, maybe just 1000 hours (that's not much over a month), maybe 3,000-10,000 hours or so for the better ones.  However, life expectancy doubles for every 10 degree temperature reduction, so the more you overshoot with temperature rating, the longer the component is likely to last.

2) In many modern devices, electrolytic caps are used mainly in the PSU sections.  Caps in switch-mode PSUs generally need to have very low ESR values, the sort of stuff that Maplin sell is unlikely to be any good.

When choosing replacements, I always narrow it down to a few of the correct voltage, capacitance and dimensions, and best temperature rating, then I go to the manufacturers' websites and dig up the full data on life expectancy and ESR.  More often that not, that process has led me to Panasonic's FM series, so I recommend them.

I have always found RS to be an excellent supplier ( http://uk.rs-online.com/web ) .  They asked no awkward questions when I set up a 'trade account' at my home address some years ago, when I was placing reasonable volume orders for prototypes of a certain device I was developing.  I haven't placed any large orders for some time now, but I still get free next day courier delivery on every order, no matter how small - literally!

Finally... have a google for 'capacitor plague', it's fun.  One theory I like (but don't really believe) is that some nasty Taiwanese spies stole an electrolyte formula from one of the big Japanese companies, not knowing it had been deliberately 'spiked'.  They subsequently flooded the market with these inferior pirated copies, which were doomed to early failure,  thus explaining the high attrition rate of consumer devices in recent years.  Like I said I don't really believe it, but it's a lovely story.   

edit:  clarified hours to months conversion

[oldfogy]

I have always found RS to be an excellent supplier ( http://uk.rs-online.com/web ) .  They asked no awkward questions when I set up a 'trade account' at my home address some years ago,

I don't use them very often, but in the past I have just walked into my local branch and purchased whatever I wanted.
As for accounts, I've never had one.

[sevenlayermuddle]

I don't use them very often, but in the past I have just walked into my local branch and purchased whatever I wanted.

I'm envious... you're privileged to have a branch nearby, there's only 16 for all of UK.   

My nearest would be about an hour's drive away, and cost about £10-£15 round-trip in petrol alone.   I think I'll continue to feel smug about my business account with free shipping.   

BTW, since we are now completely off-topic and I'm sure TD won't mind, RS can be surprisingly good value in the most unexpected of items.   I wanted some DDR2 memory a year or two ago, and they were heaps cheaper than anybody else, almost to the point where it looked like a pricing error in their catalogue.  That's no longer the case for memory (last time I looked), but they are always worth checking, even when you'd least expect it...

[tuftedduck]

@ 7lm

>>> BTW, since we are now completely off-topic and I'm sure TD won't mind <<<

I don't mind one little bit......it is fascinating to me how a thread can evolve from topic to topic. In this case, that process has been by by a perfectly logical progression which has not lost the original point in question.

Do carry on.....

[camallison]

Here is a pic of some "fat capacitors" - now I know what caused the problem.

[Help - I don't know how to put a pic in a forum posting!  Can someone help please]

[HPsauce]

Like these:
Or these:

[camallison]

Pretty much like those in the lower pic - thanks HP.

Colin

[tuftedduck]

@ camallison......two methods of posting images.

1) Upload image to an image host site such as Photobucket or  Imageshack and when done, copy the IMG link from there into the body of your post here.

or

2) When you hit the "reply" button in order to post here, the post reply dialogue opens.....go to the bottom left of that and click on "attachments and other options".....when that expands go to attach>choose .....that will open your Windows Explorer or equivalent in other OSs......navigate to the desired image and click on it. The title will appear in the box....hit the post button and your image should appear with your post.

Please note, the second method has restrictions on the size and number of images you can attach...and also that such attachments can only be seen by members who are logged int.

[oldfogy]

I have had at least 2 graphics card that had the same problem, one of which was a replacement card for the original faulty card, so same make etc and eventually same problem.

Just going back on one of my earlier posts with regards to the PowerDown adaptors, I picked up my 2 freebies today (along with a few other energy saving devices) but this latest Powerdown adaptor is now marked as being for a TV etc with a "HORRIBLY" long lead coming out of it with a sensor on the end that you program with your TV remote, unlike the "Desktop" (Computer version) version which does not have a external sensor lead.

However, E.on have a limited supply on special offer at £3.00 each (normally £18.00)
https://www.eonshop.co.uk/ProductDetails.aspx?ProductCode=1100024&Category=PowerSavingAppliances


>> Warning - while you were typing a new reply has been posted. You may wish to review your post.

[camallison]

Thanks TD - my eyes are failing again!

Here goes for the pic

[attachment deleted by admin]

[HPsauce]

Ready to pop!  8) Splendid example. 

[sevenlayermuddle]

https://www.eonshop.co.uk/ProductDetails.aspx?ProductCode=1100024&Category=PowerSavingAppliances

Don't feel I'm getting at you OF, but I can't resist commenting...

From that EON link...

TV PowerDown uses approximately 0.5 watts.

...Which is more than my perfectly run of the mill (4 years old) 40" LCD TV is specified for standby power (0.3W).

That little red light on your television and home entertainment additions such as surround sound amplifiers, DVD Players and games consoles are needlessly costing you money every hour

...I find that very misleading.  Standard intensity small LEDs (leaving aside the modern 'torch bulb' versions)  are typically rated at a maximum current of 20-30mA or so, with a voltage drop of about 2V, hence about 0.06W.    They are rarely driven at full intensity but, even if they are, that works out about 6 pence per year.  In fairness, the most cost-effective way of powering an LED is to feed it by a series resistor from a supply of (say) 5V, hence the resistor dissipates a little power too.  But the overall cost would still be measured in pennies per year.

To achieve the desired intensity, LEDs are usually fed by 'pulsed' supply, hence the actual cost of the 'little red light' would likely be just a fraction of above. 

The 'standby' circuitry in the TV (or other device) itself will also consume some power but, if well-designed, it can have insignificant impact. 

Admittedly, if you have a lot of extra equipment, like surround sound amps and DVD players that you may forget to turn off, it may help.  But a lot of equipment automatically goes into standby whenever the TV does (using HDMI signals), in which case there is unlikely to be any measurable benefit.  In any case, if your DVD player is also a HDD recorder then you'd not want it switched off at the socket else you'd miss recordings.

edit: resequenced paragraphs to avoid misleading implications.