JFET with fwd xfer admittance >30mmhos?

Although the 2N4391 switch was never speced for gfs, which is what I hope you're refering to on an older datasheet, MPS4391 developed for the same purpose was 20mS typ. Might be worth looking at the MMBF4391 switches, for function.

I only recall one or two that were higher (BSV39 70mS typ) without actually being a high power device (U244 U266), though Teledyne ($) did quite a few above 20mS (2N6453).

RL

They have all gone to lalaland. The MMBF4391 is still made by ON and Fairchild but hard to get. And it's still

I haven't, don't have one here. But in an oscillator scenario it would become quite toasty and you'd have to load it down at the output.

Most of them are like that. For me it rarely matters, you just have to make sure they don't "sing" up there. Else the FCC sends the goons out ;-)

Digikey? There they'll go to around 7c for 50k or larger qties.

Belatedly, try 2SK536 from Sanyo, if you can find a distributor.

RL

There are a few mouth-watering JFETs from Japan but many of them have become boutique parts. My clients would have me flogged :-)

This isn't one of them, but you have to buy them new through a Sanyo rep. They've been in production long enough to be available in smaller quantities from brokers.

On closer inspection, it's also not a JFET, but NMOS.

RL

That wouldn't work in really low voltage envoironments. Often one needs a JFET that can reliably start and deliver some juice as an oscillator at a few hundred millivolts.