Instant full K / Ka band in same spot every day

[joey_corleone]

I have no idea what this could be but the curiosity is killing me. I've noticed this happen on the same stretch of road for YEARS on several radar detectors.

Every time I pass a very specific part of this freeway, my Ka band lights up like a christmas tree, full bars, then goes back down to nothing. There is no construction sign or anything like that, or any "your speed is" signs

About a mile down the same freeway, it happens with K band.

I experimented tonight using special mode and here are my findings:

Ka Band: 34.732 Ghz
K Band: 24.132 Ghz.

I have an x50 Rev. 5 hard-wired to my Mustang. The voltage reading looks good, about 13.5v when the car is running.

Any ideas what this could be???

Day to day in the city I'm pretty happy with it, but on this particular stretch of this particular highway it seems to false alot.

For anybody reading this in the metro Detroit area: The spot I am referring to is 696 right around the woodward / main exit and generally in that area for Ka band going nuts, and for K band just up 696 a bit further around Couzens/10 mile exit.

I will post this in the Michigan area too just in case.

[pkquat]

I think 34.7 might be a form of Ka photoradar. I could be their is a K photo radar as well or some other K source. I have run in to random nearly full strength K from an unknown source. I think it is for doors on a store, but most don't peg the meter.

[joey_corleone]

I think I MAY have found the mystery Ka signal based on the following:

1) This is on a major intersate (I-696) ... tonight I did some more testing and noticed the Ka band signal only hits when going westbound. Furthermore, it only happens when on the actual highway, will not set off if you are in the same spot on the service drive going the same direction

2) The signal is strong and only is detected for about 1/4 mile, indicating to me that it is a very precisely aimed signal

3) Near the exit where I discovered the signal I noticed an electronic sign, mounted on the overpass. It is not a construction related sign, just gives traffic information and such. I couldn't help but notice a good sized yagi antenna mounted on the sign. The yagi was pointed directly straight (180 degrees) facing oncoming westbound traffic. Why a yagi antenna would be attached to a freeway sign is beyond me. I didn't notice any camera or anything like that

If the electronic sign is indeed the culprit I wonder why it is there???

[edweird]

Just a guess, but maybe the electronic sign is set to only display info when traffic is present?

Perhaps a system that measures the speed of traffic for reporting the time to reach locations ahead is measuring average speeds.

Or both of these.

[archangel]

Could be a drone as well?

[joey_corleone]

Could be a drone as well?

forgive my lack of knowledge of some terms, but what is a drone exactly?

[archangel]

No big deal.

A Radar drone, is a stationary placed radar gun ( Keep in mind this a very simple explanation ) that either is always running or switches on and off at intervals and has an external power source.

They are used in construction zones and on highways to annoy RD owners. They basically shoot a full blast of either K or Ka radar down into traffic, hoping that anyone with an RD will go nuts because of the full alerts, that are never cops.

[joey_corleone]

thanks for the explanation. I always wondered why my radar detector went nuts through construction zones.

I don't think it is a drone, because there is no construction in the area. The yagi thing is weird too though because this electronic sign it's up on the overpass and the antenna is pointing straight...as in if you picture its signal as a line, it would be a straight line directly above traffic at the top of the overpass

[ibleedblue]

I've run into something similar in NC and SC...particularly on I-26 heading into Charleston, SC. My old 8500 would peg every couple of miles for no reason. I finally noticed that each time I passed a pole mounted on the side of the road is when the 8500 pegged.

I know in NC and SC, on some interstates the DOT has installed small cameras on signs or poles that monitor traffic flow. The camera is a microwave detector that detects vehicle flow. Here's a picture of one. It's used in intelligent traffic design systems to let officials know if there are any backups or bottlenecks due to accident, construction, etc. There usually a small white box mounted on the pole or sign pointing at traffic. These cameras can't detect speed of individual vehicles, they only detect traffic flow. This is what I was running into on the way to Charleston. I've hit a couple of these in and around Raleigh, NC as well.

[joey_corleone]

after doing further research I have determined the Michigan DOT has also installed quite a few of these cameras just around the point I am having the issue. On their webpage you can actually view the camera feeds and also a page that tells the average speed of traffic...how can they calculate an average without clocking individual vehicles I wonder...This might be my answer. The thing is on the page they list the cameras in alot of other places on the same freeway where I don't get the alerts at all