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Old 10-23-2020, 08:16 PM   #7
momaka
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Default Re: Fake Nichicon PS series?

LOL.

I bought one of those TDA7293 boards recently as well for GP speaker tests and whatnot (but may end up using it in a small subwoofer that has a control board more complex than a space station.)

At least mine came with truly genuine ChongX caps, though. Series? - They don't say. But vent is misspelled as "VEHT". Technically speaking, the "H" is the correct Cyrillic substitute for "N" in the Latin alphabet... but I digress.
As for some of the smaller caps on my board - JWCO brand, like yours. I'm not surprised, of course, because I paid absolute bottom-dollar for the board I found. (HINT: when you find a kit that you like on eBay, look for listings of the same kit in the "similar items" area. Eventually, you should see lower and lower prices. Given that all of these use the same questionable parts, I wouldn't pay more money for any reason. Grab one for the cheapest possible... or as I like to do, always grab two in case one is DOA... and hope for the best. )

Quote:
Originally Posted by s675 View Post
I suppose that they are also not actually 50v?
If they are miniaturized 85C GP caps, they might (optimistically) be capable of handling 50V.

Just as a comparison here, I do have genuine Nichicon RS, 50V, 2200 uF caps attached on a Sony CRT TV audio processor (AK) board (I don't recall which model Sony it came from, but board p/n is 1-674-082-31 if anyone wants to know for whatever reason.) These Nichicon caps measure 18x25 mm (datasheet says they should be 20x25, but these could be custom-order for Sony), are rated for only 85C, and have a black sleeve with white text. (On that note, I wonder if that's what your counterfeit Nichicons were trying to impersonate, lol.)

With my ChongX being slightly taller at 30 mm (but only 16 mm dia.), I could give them benefit of the doubt that they may stand up to their 50V rating. But would I? IDK, probably not.

Quote:
Originally Posted by s675 View Post
Also of note is that the SEP KBL608 regulator looks like it has been re-used.
That's good.
Hopefully it came out of some junk legit power adapter. Otherwise, if new, you never know how legit the part is and whether it will do its ratings.

Quote:
Originally Posted by s675 View Post
The one thing that actually seems OK is the TDA7293 itself. Alcohol doesn't take the markings off.
It could still be a counterfeit or factory reject. Give it full max abuse according to the datasheet and you'll probably know.

FWIW, though, these boards are still pretty cool to play around with for just a few bucks. Just don't expect miracles out of them, obviously. At the same time, also expect there to be some chance of magic smoke, regardless of how you treat them.

Quote:
Originally Posted by kaboom View Post
Well... aren't we being modest here?
Those are at least 110% phony!
I think 107% is more accurate.
Ask Garage54 why.
It's a Russian YT channel for silly car mods^

Quote:
Originally Posted by kaboom View Post
They seem small for 2200/50v and may in fact be several voltage ratings below their "sticker value."
They could be as low as 1000u/25v, so beware of applying what appears to be rated voltage.
O.o
Now you're tempting me here to remove mine and give them full voltage.

Quote:
Originally Posted by kaboom View Post
By stark comparison, recently purchased late-80s NOS 10,000u/25v Panasonic snap-ins had leakage under half a milliamp after ~3mins at 25v thru a 10k resistor.
No surprise.
Good Japanese caps are good, even at 20-30 years age. Sure there were a few problematic series. But overall, I'd use an old/NOS Japanese cap any day over China garbage that doesn't even have the courage to stand under its own brand name (and tried to counterfeit others.)

Last edited by momaka; 10-23-2020 at 08:19 PM..
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