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SP8's
30-08-2010, 11:22 PM
I don't believe it ... no electronics suppliers in Dunedin can supply 1500uf @ 16v or 3300uf @ 6.3v

Have the on order via internet, but would be interested to know if anyone else has problems getting stuff like this from local suppliers ?

zqwerty
30-08-2010, 11:34 PM
How many do you want, if 1 or 2 or 3 then just take them out of old motherboards that are no longer being used.

Speedy Gonzales
30-08-2010, 11:36 PM
Did you try dick smith?

PENTIUM
31-08-2010, 12:01 AM
RS New Zealand or Jaycar. Dick Smiths are currently quitting many of their component lines.

SP8's
31-08-2010, 08:56 AM
Nobody in Dunedin carries them as a stock line ..... easy enough to get them on-line but its just a tad inconvenient.

zgwerty .... yep, and have to replace them again next week if they're on their way out. I don't have any old mobo's anyway. Just doing this for a friend.

pctek
31-08-2010, 09:10 AM
RS New Zealand or Jaycar. Dick Smiths are currently quitting many of their component lines.

Dick Smith??!! Not only are they ripoff, they have slowly stopped being a components shop.
Jaycars.

Agent_24
31-08-2010, 11:55 AM
Dick Smith have pretty much nothing left except resistors - and any capacitors they do have will NOT be suitable.

You MUST use Low-ESR capacitors for motherboards, otherwise the capacitors will overheat and die just as quick (or quicker) than the old ones.

That means getting a decent brand, and choosing the right series.

Jaycar does do 'Low-ESR' Samxon but they are not as good as those that RS-Components stock.

Your best place to buy is RS-Components or Farnell. You also need to check the specification sheet for the original capacitors and make sure ESR is the same or lower on the new capacitors. They also need to handle the same or higher ripple current than the originals too.

Getting this wrong will again reduce the lifespan of the new capacitors

Alex B
31-08-2010, 12:36 PM
Think you got it bad? Try find me 200v 10uF non polar caps anywhere.

Agent_24
31-08-2010, 12:47 PM
Think you got it bad? Try find me 200v 10uF non polar caps anywhere.

Sounds like a challenge! What are they for?

1101
31-08-2010, 01:06 PM
Think you got it bad? Try find me 200v 10uF non polar caps anywhere.

spkr xover??
you may have to make some with 2x 'normal' caps


"no electronics suppliers in Dunedin can supply 1500uf @ 16v or 3300uf @ 6.3v"
Try RS or Farnel. It will co$$t .
You can probhably get away with NON low esr nearest equivilents.
Its not allways that critical. Yes, I have repaired old m/b's (non critical use PC's) with generic caps, they run just fine.

boards with the BAD caps ran for years on dodgy caps that weren't true LowESR, so generic caps as replacement may be OK if you want to try them.


Chances are there are far more caps on this board that are bad/dodgy(& look OK), so I wouldnt spend alot of time on it.

Agent_24
31-08-2010, 03:31 PM
RS is pretty cheap and good for capacitors actually, especially as they have free shipping now.

Farnell also good but shipping cost is $15 unless you order over $80 so RS is usually always better.

The capacitors on the boards are Low-ESR no matter if they are bad brands or not, problem is the bad brands go high ESR quickly and then it doesn't work.

If you put normal caps they might work or may not even work at all, since the reason the boards stop working in the first place is because of higher ESR.

Note also that general purpose capacitors can't stand the high temperatures, and usually can't handle as much ripple current as the good ones can.

All this leads to early failure, there is just no good reason to put general purpose instead of low ESR, especially since series like Panasonic FC\FM are cheap from RS-Components and you get free shipping as well. In fact last time I compared prices with the Samxon from Jaycar, the Samxon cost more, and you had to pay shipping too.

forrest44
31-08-2010, 07:19 PM
Panasonic FC or FM series from RS is the way to go. Good capacitors, free shipping. Only problem is you have to buy in packs of 5 usually.

Jaycar have samxon and (more recently???) suntan capacitors, samxon is a decent brand, probably a lot better than the caps that went bad. Don't know about the suntan caps, I've used them for a bit and they seem fine

Agent_24
31-08-2010, 08:08 PM
I think 5 is just the minimum order quantity

Alex B
31-08-2010, 09:19 PM
Sounds like a challenge! What are they for?

A Caliber CA2000D+ D Class mono sub amp for my car 1.25kw @ 1ohm, would love to get it going again.

SP8's
01-09-2010, 09:27 AM
And they wonder why young people are going deaf .... whatever happened to the joy of listening to a crystal set ??? :eek:

Agent_24
01-09-2010, 11:36 AM
A Caliber CA2000D+ D Class mono sub amp for my car 1.25kw @ 1ohm, would love to get it going again.

What part of the amp are they used in? And what happened to the old capacitors?

Alex B
01-09-2010, 12:14 PM
Output stage I think, one of them has a raised top.

1101
01-09-2010, 12:24 PM
If you put normal caps they might work or may not even work at all, since the reason the boards stop working in the first place is because of higher ESR.


assumptions ??
Replacing with normal caps WILL often fix the board-not recommended for critical systems thou.
Ive tested some obviously bad caps with a ESR meter (& cap meter) & they can often test OK. Makes it all the stranger.

Still , normal caps do work if the board isnt worth putting too much effort into and you have some handy.
But you have to buy some, then definitely get good low ESR caps.
If you really want a reliable fix, you replace ALL the low ESR caps on that board.
Usually not worth the effort. Thats why just using whats handy is OK for a quick SHORT TERM repair to replace just the few bulging caps.

The Jaycar "LOW ESR's" Ive tested, certainly werent LOW ESR.

Paul.Cov
01-09-2010, 08:52 PM
The Jaycar "LOW ESR's" Ive tested, certainly werent LOW ESR.

Bugger!

I've used a lot of low ESR caps from Jaycar recently. On a very recent job I noticed that one replaced cap was running very hot, while it's equivalent on an identical board was cool... which kinda supports your statement further (although there may be other components in the chain to blame).
Wonder how soon that machine will be back.

Agent_24
01-09-2010, 09:09 PM
That's why I don't recommend using anything but good brand Low-ESR

The bad ones with higher ESR will heat up due to high resistance, the heat will damage them, causing the resistance to get higher, causing more heat to be dissipated.. leading to thermal runaway and quick failure.

The MOSFETs in the VRM can also become damaged to due to the high heat as well. Using these kind of capacitors is just not worth it in my opinion.

B.M.
02-09-2010, 09:18 AM
This outfit have a good selection of everything.

http://www.surplustronics.co.nz/shop/