On 8/17/2011 11:02 AM, Jim Lux wrote:

A popular scheme from WJ 30 years ago (at the advent of digital signal
processing) used 3 antennas in a triangle, and basically did
interferometry. Sampling the data and using an FFT lets you do a wide
band at one time (which is handy if you want to DF frequency hopping
radios, which became very popular in the 80s)

As far as VHF, I know a couple here in town I've seen using arrays
for direction finding. But they used four verticals in a square.
It worked quite well. We had one guy that kept jamming one of the
repeaters, and the user of said array was easily capable of tracking
him down to a shopping center parking lot where the guy was sitting
in his car. I suspect the expression on the jammers face when the
tracker tapped on his window was priceless.
The device in the car used an array of LED's in a cross configuration
if I remember right.
He had the antenna array on the back of his truck. I don't recall the
element spacing.