Author Topic: Could this possibly be a fake EPROM?  (Read 981 times)

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Offline SilverSolder

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Could this possibly be a fake EPROM?
« on: February 11, 2021, 02:56:00 am »
Not saying it is fake, but...   there are certain, ahem, indications...  that this may be the case?

 

Offline wraper

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Re: Could this possibly be a fake EPROM?
« Reply #1 on: February 11, 2021, 03:16:10 am »
IC should be M2764A from ST, however marking is fake. Speed grade and date code cannot be trusted. Most likely pull from old equipment sold as new IC. In the past I once made 2 orders of the same EPROM from the same seller with 1 week difference. First batch was fine, second batch was very old 21V EPROM from AMD instead of 12.5V from ST as I figured out by look of silicon die. And markings were exactly the same, including date code, on all of the EPROMs, despite them bearing different dies.
 

Offline SilverSolder

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Re: Could this possibly be a fake EPROM?
« Reply #2 on: February 11, 2021, 03:23:49 am »

I hadn't heard of the country of origin before....   :D
 

Offline Cyberdragon

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Re: Could this possibly be a fake EPROM?
« Reply #3 on: February 13, 2021, 06:22:23 am »

I hadn't heard of the country of origin before....   :D

It's the country where the pope goes to sing. ;D
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Offline VK3DRB

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Re: Could this possibly be a fake EPROM?
« Reply #4 on: February 24, 2021, 12:16:48 pm »
:-DD To Get Rich Is Glorious exposed as a mixture of stupidity and greed.
 
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Offline Bud

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Re: Could this possibly be a fake EPROM?
« Reply #5 on: March 03, 2021, 06:09:00 am »
Did you try to acetone it to see if the original marking comes visible?
Facebook-free life and Rigol-free shack.
 

Online BrokenYugo

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Re: Could this possibly be a fake EPROM?
« Reply #6 on: March 03, 2021, 06:40:25 am »
Yeah, see if it's painted, should be bare ceramic. I've heard of the re-marked chips but ceramic eproms is another level, who do they think they're fooling?
 

Offline james_s

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Re: Could this possibly be a fake EPROM?
« Reply #7 on: March 03, 2021, 07:11:09 am »
It's been repainted and re-marked. It's probably a real EPROM but it's most likely a used pull. Wish they'd just sell them as such, I'm perfectly willing to buy used pulls.
 

Offline wraper

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Re: Could this possibly be a fake EPROM?
« Reply #8 on: March 03, 2021, 10:07:20 am »
Yeah, see if it's painted, should be bare ceramic. I've heard of the re-marked chips but ceramic eproms is another level
What another level? It's easiest to do with old EPROM like this. Remove old paint marking with solvent and apply new.
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who do they think they're fooling?
They are fooling clueless fools of which there are plenty.
 

Offline SilverSolder

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Re: Could this possibly be a fake EPROM?
« Reply #9 on: March 03, 2021, 02:28:06 pm »

I don't actually have the item, that's what it looked like in the listing!   :-DD
 

Online BrokenYugo

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Re: Could this possibly be a fake EPROM?
« Reply #10 on: March 03, 2021, 04:23:28 pm »
Yeah, see if it's painted, should be bare ceramic. I've heard of the re-marked chips but ceramic eproms is another level
What another level? It's easiest to do with old EPROM like this. Remove old paint marking with solvent and apply new.

I'm under the impression UV EPROMs are always in a ceramic case with etched markings to accommodate the erase window and survive the heavy UV exposure in the eraser. They're usually more of a dark brown/purple color too. So painting one black as is usual in the fake chip scam is kinda glaring here, nevermind that they misspelled "Singapore".
 

Offline james_s

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Re: Could this possibly be a fake EPROM?
« Reply #11 on: March 03, 2021, 08:39:47 pm »
I'm under the impression UV EPROMs are always in a ceramic case with etched markings to accommodate the erase window and survive the heavy UV exposure in the eraser. They're usually more of a dark brown/purple color too. So painting one black as is usual in the fake chip scam is kinda glaring here, nevermind that they misspelled "Singapore".

I have a few that have been painted. They use a sort of dark brown that looks similar to the ceramic color.
 

Offline wraper

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Re: Could this possibly be a fake EPROM?
« Reply #12 on: March 03, 2021, 08:48:41 pm »
I'm under the impression UV EPROMs are always in a ceramic case with etched markings to accommodate the erase window and survive the heavy UV exposure in the eraser.
There is no reason to make paint UV resistant. It's not like chip will be constantly exposed to UV. Most of them will never be exposed at all. Laser marking started to appear only in mid 90's and became prevalent in 2000's. So marking on old chips can be easily removed with solvent.
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They're usually more of a dark brown/purple color too. So painting one black as is usual in the fake chip scam is kinda glaring here, nevermind that they misspelled "Singapore".
Nothing is painted here.
 


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