How do I test a JFET for Zero Gate Voltage Drain Current on my curve tracer?

How do I test a JFET for Zero Gate Voltage Drain Current on my curve tracer?

Zero Gate Voltage Drain Current - IDSS

What It Is:

Zero gate voltage drain current is the ID that flows when VDS is at a specified value and VGS=0.

On the curve tracer, the Collector Supply forces VDS and the gate is shorted to the source so that VGS=0V.

What The Display Shows:

The display shows VDS on the horizontal axis, and the resulting ID on the vertical axis.  The specification is met when with VGS=0 and the specified VDS applied, ID is within the specified limits.

How To Do It:

1. Set controls:

            A: Max Peak Volts to the lowest setting above the specified VDS

            B: Max Peak Power Watts to the lowest setting that satisfies (ID x VDS)

            C: Horizontal Volts/Div to display VDS between the 5th and 10th horizontal divisions

            D: Vertical Current/Div to display ID between the 5th and 10th vertical divisions

            E: Collector Supply Polarity to (+DC) for N-channel or (-DC) for P-channel)

            F: Configuration to (Base/Short, Emitter/Common)

            G: Variable Collector Supply to minimum % (full ccw)

            H: DotCursor ON

2. Apply power to the JFET:

            A: Position the Left/Right switch as appropriate

            B: Slowly increase the Variable Collector Supply % until the specified VDS is reached

3. Compare to data sheet specifications:

            Check that at the specified VDS, ID is within the specified limits