The B&D J74s i bought were unfortunately fakes too.
Really? That sucks. I guess you need to be absolutely certain the product you buy came from an authorized distributor or directly from Toshiba. Companies like MCM may not be aware of the siutation with a specific part. So their buyers may just be looking for stock and get it ouside the normal distribution chain.
Years ago, a woman that works for a Boston area electronic distributor told me of the problem with counterfeit parts. I had no idea what she was talking about back then. I do now.
I'll get the adult beverages.
I just read where the J74s from B&D were fake. Makes you wonder what our goverments are doing about all the crap comming in, or out of China. I'm I wrong?
Sorry, I feel better though!
I guess I need to devise a test circuit myself. It seems like this would be a good service to provide
I've got some really good news concerning the B&D Toshibas - They appear to be genuine.
I sent my batch to Wayne Colburn (The preamp guru of Pass Labs) who graciously applied all his expertise to measuring them. He is pleased to report back that the Idss and Noise is all within spec, but most importantly, the curve trace is genuine. These are certainly not re-branded switches.
Also of note, they have the Toshiba 2SK2013 / 2SJ313 in stock. These are use in the BA-3 Front End. They are not cheap, but they are still cheaper than tubes... I ordered a few.
So have at it, get while the getting is good, who knows how many they have.
Oh, one other thing, I'm not sure if they are actually "matching" when you order the SKU that is the pair... Perhaps it's just a 'matched set' of the N and P channel. Regardless, I strongly suggest ordering at least 10pr. Toshiba is never going to make these again.
Fabulous news
The B&D J74s i bought were unfortunately fakes too.
There's no telling what is real and what is not these days.
How do you know they are fakes? I saw a message from 6L6 that they were real...he had them tested with a Pass Lab guru???
I bought some from B&D last year.
I ran them on my curve tracer.
NG.
The IDSS is fine.
The Yfs is way off, and the shape of the curves was NG.
That doesn't mean that they did not buy another batch that happens to be good. Hard to know without testing them.
PM me, within reason I am ok with running some on my curve tracer and posting (or not) the curves.
I ran them on my curve tracer.
NG.
The IDSS is fine.
The Yfs is way off, and the shape of the curves was NG.
That doesn't mean that they did not buy another batch that happens to be good. Hard to know without testing them.
PM me, within reason I am ok with running some on my curve tracer and posting (or not) the curves.
NP, any comment on the statement in post #64?
The ones I got from Bdent were clearly the same as the bogus asian devices that I got from various sources and countries in asia. Of course my purchase happened about a year earlier, iirc.
The ones I got are not compliments at all to genuine 2SK170s.
Not even close, although their IDSS was spot on. Remarkably so.
_-_-
The ones I got from Bdent were clearly the same as the bogus asian devices that I got from various sources and countries in asia. Of course my purchase happened about a year earlier, iirc.
The ones I got are not compliments at all to genuine 2SK170s.
Not even close, although their IDSS was spot on. Remarkably so.
_-_-
Thanks Papa.Amplifier wise, if you have Jfets that operate between 6 and 20 mA Idss
and have a transconductance between 20 and 40 MS, you are in good shape.
MC preamp wise, you want genuine Toshiba or Linear Systems.
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