Okay, but that stuff is only used to find out the Vp and Idss I guess ?
So the "amplifier" itself is only made up of the FET, with the gate
grounded, the drain as output, and the source as input via 1 resistor (560
ohms) ?

Damien

PS: that's probably the last question ;-)

W7ZOI has a quick and dirty way of finding this out.
1) Connect a 1K resistor from the drain of the FET to 12v power
supply.
2) solder a 10K resistor from the source of the FET to ground.
3) ground the gate
4) apply power and measure the voltage on the source. this gives you
the pinchoff voltage (Vp).
5) short the source to the ground as well. Meausre the current flowing
through the drain (you can measure the voltage between the drain and
the 12v supply and divide it by 1000). This current value is IDss.

Now, choose a source resistor of the value Vp/(Idss * 4).

btw, you can simpley chuck all this and try 560 ohms. it should work
. the gain, noise figure etc are not too crucial. the idea is to
buffer the input and output.

- farhan