I got a some 10Ghz X-band motion detectors, an HP X532A X-Band Wavemeter, and an X421A mounted IN26 detector. I made a conical horn from W1GHZ's book out of aluminum foil and taped it on the detector. Approaching slowly I found the maxiumum output was in the 1mv range from the detector diode, so I felt it was safe to couple it directly to the waveguide.

Directly coupled, I get about 4mV max which would be 0.04mW (-14dBm) detected output from the Gunn oscillator my my X421A detector (IN26 plus matched resistor internal) is to be believed. There was a dip just below 10.55GHz.

With the X421A wavemeter in line I switched to measuring diode current as it seemed to have a better dip. 0.22mA and a good dip to 0.20mA from 10.538-10.5425 GHz. That's probably too many digits, but I can guess it's somewhere around 10.54Ghz.

So, I need to move it down into the ham band and either adjust the matching screw on the existing horn or get new antennas.

- posted by Leigh @ 20:40 z