2N5457 N-Channel Junction Field Effect Transistors 5457 JFET TO-92 25V 10mA (Pack of 10pcs)

Product looks good

I'm uncertain if these are genuinely 2N5457 transistors, but they work for what I need.

I'm an EE. Good news is that 10 devices labeled 2N5457 showed up (out of 10 ordered), fast shipping. Brand on box is "Allecin". Using a breadboard, multi-meter, 9V battery, and a couple resistors, I tested 3 or 4 of them. They all functioned as a N-channel JFETs, pinout matching 2N5457, for two simple checks. Measured IDSS (VGS = 0V) was on the order of 2.3 mA with VDS of about 8V: the ON-semiconductor datasheet range is 1mA to 5 mA, so this IDSS is technically fine. With a 1.2kΩ resistor between source and ground, gate grounded, and drain still at about 8V, measured drain current was around 180 uA, amounts to a VGS of around -215 mV: current is much lower than the typical ON-semi datasheet curves would predict for that VGS voltage level, might somewhat still be in datasheet range. Also, the devices themselves include a Fairchild-like "f" (not fully convincing) as if they are not just off-brand 2N5457 but attempts at convincing fakes. I was not able to test other key specs (like noise), etc. For me, these are probably useful enough JFETs for experimentation but I would not want to use them as replacements to fix critical audio / studio recording gear, etc. calling for the 2N5457 part number.

the show pack is defective Gate-to-Drain leaks, 0.12V, makes them unusable

Tested these and they’re not registering as jfets. Tested 5 or so with no luck.