There are a number of sellers on Ebay selling cheap tube caps from china. The image below has a couple of the ones I bought. I got a big box of them since they were cheap. When I actually got the caps, I was like, these seem a little small to have the ratings that are on them - 1000uf 450V. Now, they all tested OK - and pretty close to 1000uf. However, at 400V they will get red hot and spew their guts in no time at all < 30 minutes. I've done this with quite a few to verify that it is indeed the batch that is bad and not just one or two. So, I reeled in the voltage and have found that at 200V these only get slightly warm to the touch and seem to be OK. Now, for the price I paid, 1000uf at 200V is still a good deal. However, if you are planning on using these (remember space wise you'd need four of these to get close to the actual value that's on the package! ) you need to factor that in - it could ruin a layout you've already cut for instance. These have legitimate markings if you go to the nippon chemi con site, but still given that they aren't what they say they are... I can only think they are fakes. YMMV - but consider this the if it sounds too good to be true it probably is warning. I'd also be interested to hear if anyone else has had problems or success with these cheap caps...
An externally hosted image should be here but it was not working when we last tested it.
According to the Mfg. catalog, the largest standard value for a KMG type cap at 450v is 47uf. That should raise suspicion...
http://www.chemi-con.co.jp/pdf/catalog/al-e1001g/al-kmg-e-070315.pdf
http://www.chemi-con.co.jp/pdf/catalog/al-e1001g/al-kmg-e-070315.pdf
Hey all.. it is spelled correctly. Spacing is not so far off as to call it weird, it is after all a shrink wrap plastic outer case.......
And it's a no brainer at this point it's not the proper label... either real or not real. I did indeed remove the outside cover before i posted, they are plain aluminum underneath... not relabeled. As for warm at 200V... i mean maybe 100 to 105 F... just warm enough to be noticeable. Which yes is warmer than I'd think proper.. but seems stable.. so far. At this point, I can afford to blow them up - they are useless to me at the stated value.. so I might as well try to find a point I can use them, right!? Anyway.. Im sure im not the only one who's picked these up off ebay.. so anyone else have any feedback?
And it's a no brainer at this point it's not the proper label... either real or not real. I did indeed remove the outside cover before i posted, they are plain aluminum underneath... not relabeled. As for warm at 200V... i mean maybe 100 to 105 F... just warm enough to be noticeable. Which yes is warmer than I'd think proper.. but seems stable.. so far. At this point, I can afford to blow them up - they are useless to me at the stated value.. so I might as well try to find a point I can use them, right!? Anyway.. Im sure im not the only one who's picked these up off ebay.. so anyone else have any feedback?
There are good capacitors from China and there are bad ones. The ones used by major manufacturers are the good ones. The ones people can get from streets are usually fake ones, so as the ones from eBay, unfortunately. The bad ones sound really awful. I tried it once buying the kits and parts from Lite Audio, the company that supplies kits and parts to many online DIY kit sellers. To be honest, I hate those products. They all contain fake capacitors and parts and sound really awful. I heard that the Taiwanese brought a lot of fake products into China.
On the other hand, I have a few dozen 10,000uF 80V Nippon-Chemicon caps. I bought them a couple of years ago from ledeaudio.com at Darwin at a cheap price (around $12 a piece? can't remember exactly). I most certainly trust Lede Audio (owner David is a very nice guy, a solid engineer who worked with Radio Australia for many years and he knows what he is doing) but at that price I worried that Lede might have got some fake products. Then I built my SS amps with them and they sounded absolutely wonderful. Quality wise, they make no difference comparing to the 10,000uF 100V Vishay Computer Grade Long Life Low ESR caps that cost around $80 a cap from Farnell and cost me $50 from a wholesale distributor.
Good luck. I would consider buying tube amps from reputable Chinese manufacturers, but I would not be buying cheap Chinease parts or kits from the eBay.
Regards,
Bill
On the other hand, I have a few dozen 10,000uF 80V Nippon-Chemicon caps. I bought them a couple of years ago from ledeaudio.com at Darwin at a cheap price (around $12 a piece? can't remember exactly). I most certainly trust Lede Audio (owner David is a very nice guy, a solid engineer who worked with Radio Australia for many years and he knows what he is doing) but at that price I worried that Lede might have got some fake products. Then I built my SS amps with them and they sounded absolutely wonderful. Quality wise, they make no difference comparing to the 10,000uF 100V Vishay Computer Grade Long Life Low ESR caps that cost around $80 a cap from Farnell and cost me $50 from a wholesale distributor.
Good luck. I would consider buying tube amps from reputable Chinese manufacturers, but I would not be buying cheap Chinease parts or kits from the eBay.
Regards,
Bill
HiFiNutNut said:
As always it pays to know your vendor. Unfortunately the above assertion is true only in a perfect world - many major manufacturers including my current employer have been stung recently by counterfeit parts, it's a very serious problem - and yes just about all of these parts have been traced back to unscrupulous individuals in China.
I've been lucky so far and haven't bought any bad passive parts on eBay, but in the case of high voltage electrolytics I usually look them up before bidding and usually purchase from sellers in the US, Canada, Europe or several former Soviet bloc countries - and once vetted I usually buy from the same vendor again.
I did get taken by a fellow in Hong Kong about 7yrs ago who represented a bunch of 12AU7A/ECC82 as being genuine vintage Amperex Bugle Boys when in fact they were Richardson repackaged military surplus tested on genuine Amperex test racks.. LOL (Admittedly Richardson owns the rights to the name, but the tubes I bought were not the ones I thought I was getting, and misleading prospective buyers by omitting this fact was clearly the intention of the seller. Eventually his account was terminated by eBay for some other infraction.) I paid a LOT of money for those tubes, and the feeling upon opening the boxes was quite indescribable. They were actually nothing more than tested and relabeled 6189 and were worth maybe $5 each at the time, I paid something like $120 for five of them. Very expensive 6189...
I don't buy much on eBay from China or Hong Kong these days as a consequence, but even so there many reputable and honest vendors there if you look carefully for them. And I've not so far had a repeat experience.
Have you contacted the seller indicating that you have a problem with these parts? Unfortunately it is all too often the case that if you post negative feedback about something like this you'll get the same back from the seller. Still you might get a refund..
I would not use these for anything but bench experiments, but that's just me.
Jeb-D. said:
You forgot cardboard dumpling
Not to mention the stolen electrolyte formula that was missing a key ingredient which resulted in the rather early failure of the electrolytic caps in which it was used. (Many big name motherboard manufacturers got stung by this one.)
George, that name sounds vaguely familiar, it might well have been the same individual. I can't check as I don't think he even left me feedback.
Just for reference, a cap should not get hot or even warm when powered up with DC at its rated voltage. I think it's more likely that these caps were altered or re-wrapped, as thay are many, many times too small to be 1000/450V. The only caps of that rating I've seen have been in huge computer-style cans with screw terminals. The 50V rating suggested earlier sounds a lot more likely.
Unfortunately fake merchandise; whatever it may be is getting more and more difficult to spot.
The effort that is being expended on fakes and knock-offs almost beggars belief.
Let me share with you a personal experience
Here in South Australia, I deal predominantly with and electronics company which is known for its honesty and sale of 1st grade original components.
Not too long ago, I went there to purchase some 5v regulators, and the owner advised me not to buy from their current stock, as they were fakes.
He went on to tell me that he was fooled, and the copy was so good, that he had no reason to doubt that they were originals.
It was only after complaints by other customers and some detective work,he determined that he purchased counterfeit goods.
If a seasoned professional can be fooled, what chance do we, the casual buyers and users stand?
Maybe its time we stopped trying to purchase at ridiculously low prices and goods from non-certified vendors.
There is no bargain, regardless of cost, in what we purchase, if the goods are junk.
Unfortunately this entire fake and knock-off business reflects badly on those honest sellers who genuinely sell surplus manufacturers stock at cheap prices
The effort that is being expended on fakes and knock-offs almost beggars belief.
Let me share with you a personal experience
Here in South Australia, I deal predominantly with and electronics company which is known for its honesty and sale of 1st grade original components.
Not too long ago, I went there to purchase some 5v regulators, and the owner advised me not to buy from their current stock, as they were fakes.
He went on to tell me that he was fooled, and the copy was so good, that he had no reason to doubt that they were originals.
It was only after complaints by other customers and some detective work,he determined that he purchased counterfeit goods.
If a seasoned professional can be fooled, what chance do we, the casual buyers and users stand?
Maybe its time we stopped trying to purchase at ridiculously low prices and goods from non-certified vendors.
There is no bargain, regardless of cost, in what we purchase, if the goods are junk.
Unfortunately this entire fake and knock-off business reflects badly on those honest sellers who genuinely sell surplus manufacturers stock at cheap prices
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