SDS100 Sets off radar detector

[N7YUO]

I discovered my SDS100 sets off my Cobra radar detector.
Traveling home with the SDS100 in the cup holder, the radar detector kept repeating a distinctive sequence of beeps.
Even after I pulled into my driveway! OK, this has never happened before I got the SDS100. So I turned it off.
No more beeping. Turn it back on and the beeping started up again. Move it to the left side of the dash and the
beeping rarely happens. Hold the SDS100 up near the radar detector, and it beeps near continuous.
I am guessing that one of the frequencies it scans or the I.F. has a harmonic that the Cobra is picking up.

 

[Ubbe]

Radar guns and detectors work in the GHz range, like 10GHz and higher. Strange that it would detect something from the SDS100 that use much lower oscillator frequencies below 1GHz, so harmonics should also be low. Does the Cobra indicate what band it detected the signal?
Does it also detect IR then it could be the display or something that emits IR light. Usually radar detectors has some intelligent filter functions or they would false detect continously.

/Ubbe

 

[dave3825]

I discovered my SDS100 sets off my Cobra radar detector.

What model detector and what year car are you driving?

 

[tvengr]

The radar detector may be using an IF which detects an oscillator signal radiated from the SDS100. See if you can find a particular frequency being received on the SDS100 which triggers the detector. If located, try using IFX on that frequency to see if it eliminates interference to the radar detector.

 

[kruser]

Radar guns and detectors work in the GHz range, like 10GHz and higher. Strange that it would detect something from the SDS100 that use much lower oscillator frequencies below 1GHz, so harmonics should also be low. Does the Cobra indicate what band it detected the signal?
Does it also detect IR then it could be the display or something that emits IR light. Usually radar detectors has some intelligent filter functions or they would false detect continously.

/Ubbe

I guess you must wonder how well the filtering is for out of band radar signals.
I would think Cobra covers those bases well but perhaps something snuck in after a circuit change.

 

[KevinC]

Also reported here…

SDS100 - a few oddities...

I have noticed a couple of quirks on my SDS100. First I'd have to put it on a scope to determine the freq. When connected to an external speaker, the audio out, (during a transmission), has a pronounced low frequency 'rumble'. It's fairly low, maybe 30-40Hz, possibly lower? Does everyone also...

forums.radioreference.com

 

[captainmax1]

I have never heard of a scanner setting off a radar detector. They emit no signal. Is this an old detector or new vehicle? Most new cars have safety sensors all around them that will constantly trigger the older radar detectors. I had to buy a new detector 5 years ago because of this. No false alarms now. I use the Uniden R3 and it's the best detector I have ever used by far. They have newer models now.

 

[StickyBit]

I have never heard of a scanner setting off a radar detector. They emit no signal. Is this an old detector or new vehicle? Most new cars have safety sensors all around them that will constantly trigger the older radar detectors. I had to buy a new detector 5 years ago because of this. No false alarms now. I use the Uniden R3 and it's the best detector I have ever used by far. They have newer models now.

Local Oscillators produce very low power but measurable emissions as an unintended byproduct of how they function.

I discovered my SDS100 sets off my Cobra radar detector.
Traveling home with the SDS100 in the cup holder, the radar detector kept repeating a distinctive sequence of beeps.
Even after I pulled into my driveway! OK, this has never happened before I got the SDS100. So I turned it off.
No more beeping. Turn it back on and the beeping started up again. Move it to the left side of the dash and the
beeping rarely happens. Hold the SDS100 up near the radar detector, and it beeps near continuous.
I am guessing that one of the frequencies it scans or the I.F. has a harmonic that the Cobra is picking up.

Yes, the SDS100 and SDS200 and various RADAR detectors have been known to interfere with each other:

• https://www.rdforum.org/threads/91494/post-1321393
• https://www.rdforum.org/threads/87057/post-1254882
• https://www.rdforum.org/threads/87057/post-1256507
• https://www.rdforum.org/threads/107057/post-1551018
• More: https://www.rdforum.org/search/?q=SDS100+false&o=date

 

[Ubbe]

X-band seems to be the most problematic band, and I even think that they move away from those radar guns. It is known to trigger radar detectors X-band from automatic door openers radar horn. One guy said he got false trigg from his scanner on all radar bands, so it seems that the IF frequency used in radar detectors, they don't use the 10GHz -50GHz frequency and amplify but instead immediately mix it down to a lower frequency, and then the scanner has that IF frequency in its oscillator range. And that indicate that the radar detector have bad shielding of its IF section as the signal can go so easily thru the chassi and directly hit the electronics.

/Ubbe

 

[Ensnared]

Cedar Electronics is the parent company over Cobra, Beltronics, & Passport/Escort.

When I owned my first Passport Max II, my Cobra 29 would trigger the laser alert. In fact, it would also put the alert on the GPS screen connected to the radar detector.

I asked a radio technician about this and he suggested the magnetic mount with a 5-inch rubber boot coupled with my power plug in setup was likely not well-grounded. When I called Cedar, they were completely clueless.

So, I fashioned a wire to the radio & metal below the seat. It worked well.

On occasion, I would trigger this for a good laugh.

When I lost the radar detector, I bought a newer model, the Passport 360. As opposed to the previous model, this one is shielded.

I am using the same setup. No more false alerts have occurred with laser.

One more thing. My SDS 100/436HP are friends with my Cobra 25/29, Anytone 500-M and Passport 360. We are one happy family.

 

[tvengr]

I have never heard of a scanner setting off a radar detector. They emit no signal.

Local Oscillators produce very low power but measurable emissions as an unintended byproduct of how they function.

I have used a scanner and directional antenna to locate radio-controlled model planes down in wooded areas by homing in on the local oscillator signal from the receiver in the plane. An oscillator is a low power transmitter.

 

[Ensnared]

I have used a scanner and directional antenna to locate radio-controlled model planes down in wooded areas by homing in on the local oscillator signal from the receiver in the plane. An oscillator is a low power transmitter.

 

[Ensnared]

Here is something else to chew on:

Can the Spectre RDD Detect Your Radar Detector - Radar Roy

 

[dave3825]

I found it to be much cheaper to just do the speed limit. Saved hundreds on detectors over the years as well as any fines a judge would impose.

 

[wtp]

back when the Florida Highway Patrol was on 154.68 Mhz i used my scanner to find them.
i thought one day i had a false reading, but the guy in the Mustang next to me had on his uniform.
after he passed i spotted the 18 inch whip on the rear deck and could see blue lights from the sun behind us.
and that was with the scanner on the seat next to me.

 

[Ensnared]

I found it to be much cheaper to just do the speed limit. Saved hundreds on detectors over the years as well as any fines a judge would impose.

Well, to me, this is a cop detector. It is my hobby, cat and mouse. I am rather hypervigilant.

Most of the time, I am within 5 MPH of the posted speed limit. There are times when I don't want to risk getting pulled over. There are times when I want to stay alert toward the end of a long trip. All of the bells and whistles in my car keep me wide-awake.

This also alerts me to where the cops are when something happens on the scanner.

Last Thursday, 4/20, I heard radio traffic about a chase on IH35. I promptly alert truckers on the northbound side. Then, my detector went nuts. I looked up and saw a formation of DPS traveling northbound. They were chasing someone who was wanted in Chicago. The chase started in Williamson county and ended in Waco.

The prize? I have a news story to back up the recording.

Illinois woman in custody after high-speed chase on I-35 ends in Waco

 

[captainmax1]

I found it to be much cheaper to just do the speed limit. Saved hundreds on detectors over the years as well as any fines a judge would impose.

A radar detector is good to keep you alert and aware of your speed limit. Sometimes when you have been driving a lot, you might not check your speed as often or when you're moving along with the traffic flow, they might all be speeding. The occasional beep will remind me to check the speed limit. On my latest vehicle, the last speed limit sign I passed will project on the heads-up display. Sometimes the speed limit will go from 55 to 25 and if you miss the sign, you will be unknowingly speeding, especially if everyone around you misses it too. For me, radar detector is just another situational awareness tool like the motion sensors and cameras around vehicles these days. If I turn all the safety features on, todays vehicles will automatically speed up and slow down as the speed limit changes, stop and accelerate along with a vehicle in front of me and steer itself if the lane lines are visible enough. It will brake itself before it lets me hit an object in front or back of me. Amazing how much technology are on vehicles since I first started driving in 1970. I guess it's been over 40 years since I had a speeding ticket or an at fault wreck. Knock on wood. Back to the subject of this thread, my two SDS100's have never set off my radar detector even within a foot of the detector, but as always, YMMV.

 

[Ubbe]

There are several $100-$200 models of a speed warning device with built in GPS that has all the speed limits programmed and can be updated online. Then the device show your actual speed and when you go just a little bit faster than allowed it shows a warning and when going even faster that could render a speed ticket it beeps and warns you about your excessive speed. In some countries, like mine, it is not allowed to import, sell, or even have a radar detector in your possession. Then those speed warning devices becomes very popular and they also have all the positions for fixed and permanent speed cameras programmed that will give you an additional heads up warning.

/Ubbe

 

[phask]

My experience, with Ohio MARCS is there are just a few freqs. that set my RD off, and not 100%. Pretty sure it depends on the Sites freqs. as I may be in certain areas and different sites and all is fine while others may set it off constantly.

FWIW - nothing new, Uniden was made aware during Beta testing and did nothing.

 

[dave3825]

A radar detector is good to keep you alert and aware of your speed limit.

The occasional beep will remind me to check the speed limit.

When I use Waze, it will alert me when approaching and going over the posted limit.

Well, to me, this is a cop detector.

Does your radar detector still know where the cop is even if the cops radar is off, and he is not transmitting on his radio?