Does an n-channel JFET require positive or negative value and why??

Question

Does it require a pos. or neg. value for Vgs?? and what does JFET stand for?

Answer 1

The N-channel JFET is normally conductive, requiring a negative bias voltage to turn it off. It will draw no input current for negative gate voltages, but will draw input current for positive input voltages. A positive voltage must be applied to the drain terminal with respect to the source terminal in conjunction with a current-limiting resistor in series. As the gate-to-source voltage is made less negative than, say, -5 VDC typically, current begins to flow through the device.

Answer 2

An N-channel JFET (= Junction Field Effect Transistor) is normally biased with a positive drain supply and vgs negative.