V1's not picking up side of street radar signs

[WhiZa]

I'm sure you've seen those signs on the side of the street that show you how fast you are going. In the past my radar dector would go off before I saw one. Now I fly right by them without a peep. My V1 goes off around stores and random locations so I know it is picking up signals (X, K, and Ka). Do these side of the street signs use a different band?

[jimbonzzz]

Here's what Mike V has to say:

The failure to alert to a particular speed sign might have one of several causes:

1) The speed sign may employ an FM-CW modulation technique to sense the direction of vehicles in its field of view. This feature is used to isolate departing from oncoming traffic. The V1 does not recognize FM-CW modulation as a valid police radar signal and tries to reject it. FM-CW is allowed for license-free "Part 15" devices by the FCC. FM-CW is not allowed for police radar. There are numerous traffic-volume sensors using FM-CW spread all around metropolitan areas these days that detector owners would rather not produce an alert. Otherwise freeway driving (in Cincinnati, at least) would be very annoying. It's a good thing that the V1 rejects FM-CW modulated signals.

2) The speed sign may have drifted out of the police radar band from aging or temperature. "Part 15" devices are somewhat notorious for this behavior. Automatic door sensors and Doppler security sensors are both "Part 15" devices, too. Few automatic door sensors use FM-CW because of the added expense. The speed sign devices can afford the added cost of including the FM-CW modulating hardware.

3) The V1 in question may need for our service department to have a look at it to make sure it is operating correctly."

[nomore55]

one of these radar sign boards is positioned in front of my son's school this week. The V1 doesn't pick it up until I'm within 25' of the sign and then it gives an X band warning. However, the X50 picks up the same sign board at least 1/3 mile away and displays it as K band, which I believe it is.

I guess Mikey has the superior design in this scenario.

[Bear-Tweezy]

one of these radar sign boards is positioned in front of my son's school this week. The V1 doesn't pick it up until I'm within 25' of the sign and then it gives an X band warning. However, the X50 picks up the same sign board at least 1/3 mile away and displays it as K band, which I believe it is.

I guess Mikey has the superior design in this scenario.

Might wanna send that V1 in

[nomore55]

No, there's nothing wrong with the detector. It works flawlessly - - refer to Jim's post above. The detector is doing what its been designed to do.

[WhiZa]

Thanks for the info. Is there any cheap way to detect FM-CW?

[Bear-Tweezy]

No, there's nothing wrong with the detector. It works flawlessly - - refer to Jim's post above. The detector is doing what its been designed to do.

How can you be so sure???? Yeah i agreeit could be part one, but what about part three????????????

[Switchback]

Thanks for the info. Is there any cheap way to detect FM-CW?

Why would you want to? it is not used for traffic enforement! so why would you want to be alerted to it? it cannot be used for ticketing!!

it makes about as much sense as getting a detector that alerts to fire hydrants!!

[ES13Raven]

No, there's nothing wrong with the detector. It works flawlessly - - refer to Jim's post above. The detector is doing what its been designed to do.

I would still send it in to be sure...

Better safe than sorry! :wink:

[WhiZa]

Why would you want to? it is not used for traffic enforement! so why would you want to be alerted to it? it cannot be used for ticketing!!

it makes about as much sense as getting a detector that alerts to fire hydrants!!

Agreed. I just wanted to make sure it's FM-CW that they're hitting me with and not a faulty V1 :shock: