Genuine Rubycon or fake on eBay?

[Half-Saint]

Knowing lots of counterfeit product are coming from China, I'm curious if these are legit:
http://cgi.ebay.de/ws/eBayISAPI.dll?...=STRK:MEWAX:IT

Around here you can only buy Jamicon or Yageo mobo caps and I'm looking for something better

Cheers
SainT

[Big Pope]

Re: Genuine Rubycon or fake on eBay?

Don't know it is fake or not, but surely Rubycon have already stopped MBZ series since year 2006.

[Topcat]

Re: Genuine Rubycon or fake on eBay?

Here's some guaranteed genuine ones:
https://www.badcaps.net/store/produc...products_id=38

[i4004]

Re: Genuine Rubycon or fake on eBay?

btw. topcat what is the shelf life of these caps, according to you?
say, 20°c, dark room, average humidity etc.

is it 3,5,7 or even more years?

offcourse reforming can be applied....

oh yeah, good thing you're shipping int'l now.
prices seem to be ok.

[Topcat]

Re: Genuine Rubycon or fake on eBay?

I have no idea on the shelf life of them. They don't stay around here long enough for it to even be a concern.

[i4004]

Re: Genuine Rubycon or fake on eBay?

if one counts on reforming, they can probably last as much as those in usage, ie LOOOOOONG time...

i mean, i have some OLD rubycons taken out of some car radio and they're still pretty fit when i look at their esr...
unused for some 20+ years.

[bigbeark]

Re: Genuine Rubycon or fake on eBay?

I acquired a few cartons of Rubycon MBZ and ZL caps from Ebay. Manufacturing dates seem to be around 2003.

I have checked them with my ESR and Capacitance meters.

I can report that these are the gold standard of caps. The capacitance variance listed for most caps is plus or minus 20%.

These Rubycons measure out to within 1% of the listed capacitance.

When I test other caps, I generally find that the capacitance is usually way off on the high end. I measured cap value of 2500 on 1500uf Jamicons and Wendells.

Just pulled a Sanyo 1500uf off an Asus A7V133 mobo, the actual capacitance was 4700!!



s

[robert]

Re: Genuine Rubycon or fake on eBay?

Shelf life does seem to be rather high for good caps.
I still have a huge stock of 2001-made ZLs and all are perfectly in spec, never had trouble (i did blow 2, when i recapped a battery charger, soldered in the new caps according to the + and - printed on the PCB, and within a minute it blew up. Turned out they printed it the wrong way round)

Higher capacitance then spec has 2 causes:
-capacitor sitting around too long, oxide layer getting thinner, increasing capacitance and reducing voltage. Can be reversible by applying voltage (with limited current), but on crap caps, it often isnt.

-capacitor having huge leakage current, which confuses the meter. Most cap meters measure the charging time constant, which obvioulsy increases when theres leakage reducing the charge current avialible for actually charging.

[i4004]

Re: Genuine Rubycon or fake on eBay?

or

sitting too long=oxide layer getting thinner=bigger leakage current

http://www.vmars.org.uk/capacitor_reforming.htm
"So what goes wrong with electrolytics?
Electrolytics use a very thin film of oxide on the positive electrode as the "insulator" between the plates. They need a small leakage current to keep this oxide layer in place. If left unpowered for long periods the oxide layer can break down, making the capacitor into more or less a dead short.
When power is applied to a capacitor in this condition, it may quickly re-oxidise..."

>Shelf life does seem to be rather high for good caps.

i was justing measuring some that are not so good, and they seem to withstand the test of time just fine too...
no shorts, good esr readings...

overall, lytics can last awfully long time, offcourse given that chemistry was ok and they're not on too warm places...
as demonstrated by such things
http://www.youtube.com/watch?v=JM1sH...eature=channel
and mere amount of stuff he has
http://www.youtube.com/watch?v=YzpH3Rq5CQ8
he also has videos of repair...yes, some lytics do dry there, but hell, it's OLD stuff!
http://www.youtube.com/profile?user=...47/VYSoDazI5tE

so lytics lasting 40 years don't seem to be uncommon at all.