I have some 2SK2013/2SJ313 with the same batch number. It bothered me too, but they curve trace to within spec.
Dunno....
Dunno....
I stress "tested" some "331" marked 2N3906 from an AliExpress assortment kit, against U.S. made 2N3906, obtained from reputable supply sources, in a badly made switch that basically let the device draw unlimited current until it failed. The U.S. transistors instantly failed, sometimes spectacularly exploding. The "331" devices could hang in for a second or so, sometimes a bit longer, before failing gracefully, usually with just a cracked case, although one let out an impressive plume of noxious smoke for several seconds.
I also had and tested some smd SOT-23 '3906 parts from another AliExpress assortment kit, that are probably also "331", and these seem at least as good as the U.S. parts for a switch application.
I think these assortment kit parts are probably okay for hobby type use.
That is interesting. To me it proves those two groups are different because they behave differently.
However, transistors failing sooner does not mean they are worse or of lesser parameters. It may mean they are less current limiting, draw more current and self destruct sooner.
I do not like to have customers have to ship there amp or electronic equipment back to me because of some sub - par electronic component. So it's why I buy from select place. I worked @ Xytec in the 90's and they purchased all parts from arrow and never had a failure.
I wonder why someone would fake such small inexpensive devices. It seems akin to counterfeiting pennies.
They likely are just using a smaller die - which means they will not handle the current - if you buy from a known company you are less likely to get bad parts. I've been buying parts since the late 80's and I have been on Ebay since 1998 selling parts that I obtained when Xytec went out of business, and over the years I have seen a lot of sellers come and go and no clue how these sellers with 240 negatives a month can even be on Ebay - I have 100% rating..
How much smaller of a die can you possibly get than a 2N3906? The “fakes” might have been bigger (and perhaps slower, with less gain).
For a 2 cent part it seems silly to fake...
They could have put the wrong marking by mistake.
As for parts, sometimes you do not have a choice except to substitute as the original maker stopped making them.
They could have put the wrong marking by mistake.
As for parts, sometimes you do not have a choice except to substitute as the original maker stopped making them.
There was a guy who set up to counterfeit nickels. If you make a lot of them it looks like real money. Nobody actually looks at nickels. And this was days when cigarette machines and jukeboxes took coins, so banks were used to operators coming in with large bags of coins.
His main mistake was to order the *exact* alloy the Mint used. Someone thought that was odd and went to his house to see what he was doing. In retrospect he cudda used a similar alloy-- his fakes did not have to look beautiful forever. OTOH Henning made hundreds of thousands of bad nickels, today widely available $5-$15 (so worth more than most $0.05 pieces).
There's also a thing for stamping an "S" to make a common 1924 Buffalo into a San Francisco Mint buffalo (I think I got that right).
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Brooklyn Woman Finds Counterfeit Penny Made of Gold - The New York Times
"Brooklyn Woman Finds Counterfeit Penny Made of Gold
A “penny” made by a Seattle artist out of 18-karat gold was put into circulation in Los Angeles in 2007 and found by a graphic designer in Brooklyn two years laer.
One afternoon in March 2007, Jack Daws stepped up to a newsstand in Los Angeles International Airport with a handful of change, including a counterfeit penny made of 18-karat gold that Mr. Daws, a Seattle artist, had fashioned. He carefully put the counterfeit penny, dated 1970, down on the counter, counted out enough change to pay $11.90 for a Hustler magazine and left.
...when Ms. Reed was paying for groceries at the C-Town supermarket in Greenpoint, she noticed the penny because the gold color had started to peek through."
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The question of counterfeiting nickels is do they cost more than 5 cents to make? My guess is they cost about a buck apiece unless you really *are* making a gazillion of them. And the exact alloy the mint used would have some sort of premium attached to the price tag.
“Captain, I must have some platinum. A smack block - five or six pounds...”
“Captain, I must have some platinum. A smack block - five or six pounds...”
