Simplistic NJFET RIAA

[MASantos]

[studeb]

i find polida as a seller on ebay, but they have not sold anything like 2sk170, last sale in 2007

and they are listed as being in Belgium not China

Originally Posted by The Space Egg Corp

Hi FET fans !!!

The postman got here from China today ( he looked exhausted ! )...
...with a 'test' of 10 Toshiba K170-BL...
...from eBay seller 'Polida'.

[MASantos]

search for 2sk170 on ebay and some pictures of sale item have polida written, it is not the name of the seller

[studeb]

got it
polida2008 is seller

[AndrewT]

Space Egg, looks like you have 2sk170.
Check the pinch off voltage.
You need a megohm resistor for this test.
From memory expect the lower Idss to have pinch off near 400 to 500mV and the higher Idss to be around 500mV to 700mV.

http://www.forsselltech.com/media/at.../JFET_Jig1.pdf
Measure Vgs/Vp (-ve value) when the 18V of the batteries are across the 1M & the jFET.

Instead of an ammeter use 100r and a voltmeter reading to 1.999V for the other tests.

[Salas]

See #8380 also.

[The Space Egg Corp]

MASantos...

...Joking aside...( Ha Ha ! )

I have been looking at the 'audio testing' possibilitys.

I think my obssesion level will reach about 101% on this project !!!
So...

Was looking at this...
...There's a thread somewhere, called ' JFET Bride Of Zen '...
...Here's a few versions of what they are messing with...
...Transistor-socket...BINGO...drop 'em in...pull 'em out...!...

Good for 'listening' to capacitors, resistors, WIRE !, chewing-gum foil, etc. etc.

Am thinking to make a 'balanced' something-like-this...
...could be interesting...
...a few component sockets...
...get a shunt-reg made first for decent PSU.

BOOM !

Si.

PS...My main concern with the eBay seller mentioned, is that CLEARLY the JFET's I recieved, are from NUMEROUS different batches, possibly 'left overs' from some kind of 'vague factory matching' somewhere.
At least with the 'ammo-belt' theory, you are getting a 'stream' right off the line.

Question...
...How much 'variation' or 'similaritys' or 'spread' do people who have bought 'ammo-strip' get ?

Salas ? Merlin ? Ricardo ?

[atupi]

If my Simplistic goes to a DCB1 what should be the minimum value of the output cap of Simplistic ?

[merlin el mago]

Originally Posted by atupi

If my Simplistic goes to a DCB1 what should be the minimum value of the output cap of Simplistic ?

What's the input impedance of your DCB1?

[atupi]

I don't know, maybe Salas knows better. I suppose is high, tens of kohms.