Can anyone enlighten me why I get a K/KA alerts when passed by some 18 wheelers. Is it because they carry some sort transponders?

 

Most trucks have CB transmitters but lots have bi-directional GPS where they receive signals from the government GPS satellites, calculate their position, and then transmit that location back up to a commercial satellite which relays that data to the corporate computer which is tracking the shipment. They probably use Ku which is 10.9 to 12.75 GHz which is just about half the frequency of the K band radar which is 24.125-24.150 GHz. So the first harmonic of the Ku band satellite transmitter is right at K band giving you the false alert.

Oddly enough I work at a television broadcast facility and neither our 140 watt C band or 80 watt Ku band transmitters set my V1 off ... but the stupid automatic door sensors do.

 

Wow, those expencive transmitters cant set it off, but a cheap automantic door sensor can LOL

It happens

Heres a question, Do the CHP or police ever use the X band? im wanting to know, i would like to turn that band off because of all the annoying beeps ever time i pass buildings.
My solo2 i can turn off any of the bands that are used

 

The only time I had a true x-band hit on my Passport 8500 was coming around a corner in the back mountains of TN and passing a circa 1980's sheriff's car (with a really old sheriff driving). If I remember correctly, only maybe the NJ state police or another North Eastern state still use x-band.

 

X is no longer used. My Eclipse head unit sets of my laser alert. And those signs some on a hitch with the posted digital speed will emit a strong Ka band.

 

The radar varys by location.

In Oregon along the 5 freeway they set up X-band transmitters with those automated signs ... "The speed limit is XX and your speed is XX". I went through a couple of them that set my detector off telling me that the signals were X-band. A few mile further down the road the thing started going off again. Checking the band indicator showed K-band and I slowed down in plenty of time to see the state trooper working his trap.

Here in SoCal I've never seen an X-band that wasn't a false alarm.

 

this saturday in nc i've got x band signal from the police car. this was the first time since i have my solo2. i was wondering about the same thing too, cause in two years i never had a real signal driving in atlanta.

 

:lol: I too work at a broadcast facility and have noticed the same ...