"Damien Teney" wrote in message ...
Thanks I've understood what you mean ;-)

bias the FET for nominal current at about half the Idss.

As I'm not (yet) familiar with such circuits, so could you tell me how to do
this :-$ ? Thanks.

Damien

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

- farhan