Here you go, the DGS#SGD pinout is standard for this package type.

VDS=-50V, 2*0.2W,gm=12 mS typ.
Idss: Y=1-3,GR=2.6-6.5,BL=6-14mA.


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burbeck said:
thanks James

any one succesfuly substituted 2 jfets for this dual?

matching might be the main thing to consider.
it is used on power amp input diff any advice?

2SK150 is a single chip JFET and has transconductance of [email protected], [email protected] while maintaining low noise. Something comes close to this is two matched 2SK117 pasted together (of course, the drift would be worse). Toshiba lists 2SK389 as a substitute for 2SK150 but 2SK389 has higher transconductance so the frequency response would be different. Pasting together two matching 2SK170 is a good substitute for 2SK389 electronically (except for the drift). uPA63 or uPA68 are good substitute but I don't know where one can get them. Good luck!

Just kidding, the K150 is less than $3 each at places like Grandata if you're not in the mood to fill Mark's pockets.
Some US stores list the SK150 as low as 1 dollar 50.(some folks don't get my cynicism)

Interesting amp, never seen a schematic with a K150 on the input, only as cascode devices for higher octane dual JFETs.
Mr Satoru,

apparently a lot of folks started this hobby +2 decades ago.

I manage to trace 20 year obsolete parts on a regular basis, which is not that surprising considering the sheer volume of the global distribution.
Just recently i acquired a number of metal can selected V-grade dual JFETs at a fraction of the current average commercial value.
A component i already have more than a few of, sourcing the J type complementary part in any Idss grade has been much less availing.
Astonishing is how commercial component vendors continue to succeed in sourcing rare parts in larger quantities.