Has anyone here built a GOOD antenna/network analyzer?

From what I can determine, the MFJ stuff doesn't resolve the sign of
reactances, nor does it have a computer interface. I was looking at Analog
Devices' AD8302 IC (http://www.analog.com) for this application. This is a
single-chip device that measures the gain and phase difference between 2 RF
inputs up to 2.7 GHZ with very high accuracy. It occurred to me that this
chip, together with a PIC that has A-D conversion, and a computer-controlled
station transceiver, could form the basis for a very nice programmable
antenna/network analyzer that would run rings around the MFJ units.

Comments?

Joe
W3JDR