Hi,

Our company is new to the RF characterization. We are trying to meas S-par on a JFET (VGS=0, so it is only a 2-term device). DC current is 450ma and AC spectrum goes up to 2GHz. There are several proposals now. So let me describe the most promising one.

A NA (Network Analyzer up to 3GHz) port1 connects to RF coupled port of 1st directional coupler with JFET connects to RF port. This acting as ac signal injection. Port2 of NA connects to RF coupled port of 2nd directional coupler with JFET connects to RF port. This is acting as meas port. JFET is connected to a 5V DC with 11Ohm resistor. All couplers terminated with 50Ohm.

Would this setup work?

Thanks

David