I was bored and started thinking about how some of the older radar detectors had antenna's that you could "tune" or adjust with tuning screws located on the circuit board. So, I decided to perform a little open heart surgery on my old Bel 966W that I bought used off ebay awhile back. I wanted to see if I could bring it back to it's glory!! :P
Basically what was happening was I'd turn the RD on and it would just start alerting to Ka for no apparent reason. In fact, it was falsing so much the last time I used it the Ka was alerting nonstop.
So, I took the Bel apart and located what I believed to be the tuning screw and started to slowly turn the screw first clockwise, then counter clockwise until the Bel stopped falsing to Ka. Once I got the Ka to stop I tested my adjustments by plugging in my old Cobra and seeing if the Bel would detect it. Once I was happy with the results I decided to put everything back together and take it for a test spin.
The results were pretty good from what I could tell. It did alert K band once to some known X band door openers. However, everything else was right on the money. In fact, the sensitivity with X and K band seemed ABOUT on par with my RX65.
Granted I wouldn't trust this RD to speed with, but it doesn't even detect all of the Ka range, so it is just for playing around with. City mode seemed to filter pretty good too. Keep in mind this RD is from 1992 as shown on the circuit board. I'll try to get some video footage of it in action as soon as I can.