There's 2 levels of OCD
1) Being OCD about details that make the biggest impact on the end result.
2) Being OCD about details that matter very little to the end result.
I recognise I am OCD about this stuff but I try to be intelligent about it
Then there are other "people" who are just OCD, and aren't even aware they have it.
These types usually fall into category (2).
Hahahahaha
1) Being OCD about details that make the biggest impact on the end result.
2) Being OCD about details that matter very little to the end result.
I recognise I am OCD about this stuff but I try to be intelligent about it
Then there are other "people" who are just OCD, and aren't even aware they have it.
These types usually fall into category (2).
Hahahahaha
Alternatively open the bloody multimeter inspect what current sense resistor is used and bloody upgrade the current sense resistor to something good.
You now have a good Ammeter using a current sense resistor of known quality.
BOB's YOUR UNCLE
> I'm testing proper Idss, no resistors in source or drain....... DMM connected as mAmeter in drain
So DMM as Ammeter does not use a current sensing resistor.
And the ammeter has a lower tempco than say a S102.
Cheers,
Patrick
oh yes, and that's very relevant, for practical purposes
you're clueless bstrd
everybody around knows that Bubba Flocchini is my Uncle
as I said, my OCD stops at Green LEDs; still waking from one repeated nightmare, why I didn't include them in few constructions!!
And where did you get that jig for holding the fets?
Gift from Papa?
NIANNIANXINDIANZI SOT23 6L SOT23 To DIP6 IC Programmer Adapter Chip Test Socket|ic socket|ic chip - AliExpress
Have fun codyt! I'm about to start mine as well now that my Pearl 2 is finished. Just waiting on my Semisouths from jama via South America.
ZM, I may have gone too far. The Semisouths are SEJP120R063 or double die 120's. I've read through other posts they should behave as 120's just better dissipation. Any thoughts on changes needed for the circuit with these or just bang em in?
I forgot to ask - you going SS down, or SS both?
these are depletion parts, while Semisouths used here are enhanced
depletion are like triode - normally ON , enhanced ones are normally OFF , so their governing voltages (Ugs potential) are opposite in sign
anyway, we like depletion ones (in other circuits) but IJW, you posted link to, is having Ugs greater than (-) 10V for Iq of our interest, and that's complication - you need either elevated rail for that difference amount (difference between regular part Ugs and this one Ugs) or to introduce auxiliary rail, if possible in construction
edit: though, it can work in circuit as Singing Bush, without penalties - there is already auxiliary circuit for biasing, so no biggie
send me a pair and I can test them in vivo in Mighty SB , why not
depletion are like triode - normally ON , enhanced ones are normally OFF , so their governing voltages (Ugs potential) are opposite in sign
anyway, we like depletion ones (in other circuits) but IJW, you posted link to, is having Ugs greater than (-) 10V for Iq of our interest, and that's complication - you need either elevated rail for that difference amount (difference between regular part Ugs and this one Ugs) or to introduce auxiliary rail, if possible in construction
edit: though, it can work in circuit as Singing Bush, without penalties - there is already auxiliary circuit for biasing, so no biggie
send me a pair and I can test them in vivo in Mighty SB , why not
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@twitchie - thanks for link! Just found and ordered from fleabay. Too bad I have to wait a few weeks to get it. We’ll see if I have the patience. 
@codyt - I only bought two Semisouths, so I’m only going SS down. To satisfy my matched quad appetite I have a quad of 2SK182ES on the way from Japan. But that’s another amp altogether.
@codyt - I only bought two Semisouths, so I’m only going SS down. To satisfy my matched quad appetite I have a quad of 2SK182ES on the way from Japan.
But that’s another amp altogether.
Of course I don’t have the patience to what for the testing jig. I’m sure it will come in handy again though. Revised my jfet sorting tray. I drilled a series of 5/8” dia. holes halfway into a piece of wood flooring with a forstner bit. Thanks for the idea ZM. Starting from the beginning testing until the reading settles. We’ll see how long it takes me to get through 50 jfets.
