This is an inside view of our X-Band Gunnplexer transceiver (book‘s Figure 12) that should help you build your own units if you follow the schematics shown in the book’s Figure 11 . It is used throughout Chapter 1 for experiments in microwave optics, in Chapter 6 to measure single-slit diffraction, and in Chapter 7 to experiment with Quantum Tunneling.
[...] Gunnplexers are becoming scarce in the surplus market, but X-band motion detection is very much alive. X-band detection modules are available for OEM applications, and fortunatelly, Parallax has a unit based on this module available for $34.99. [...]
After much searching online, I found 2 gunnplexors by C & K systems in Portugal on Ebay. The trick was to look for ham radio items. I paid $16.00 each, he had two left as of october.
Now if I could only be absolutely positive I have the connections right for the Gunn diode and mixer on the gunnplexors. I could find no mention of these particular gunnplexors on line, C & K may still be a security company with no online presence.
looking inside the gunnplexor body, just inside is a barbell appearing metal tube approx 3 mm diam with thicker end pieces.
This is the mixer?
There is a resistor and Zener diode linking this terminal to ground.
Deeper in the body are two sections of thin metal tube , one extending from the top and the other from the bottom, meeting in the middle with a thin white round piece- looks like teflon- in between. There is a 0.1 uf ceramic cap linking the terminal to ground
This is the Gunn diode?