Radar Gun Output

[Beeej259]

I have read many posts which members of the board state that radar guns put out the same amount of power no matter what the range is set at. If this is true, how come NJ state trooper X-Band guns are about 1/8 the power of my local town X-Band radar guns? I can pick up my town guns from almost 1 mile away and the signal maxes out my V-1 about 1/4 mile from the cop. When I'm on the turnpike in NJ and I come within 100 feet in front of a cop running radar, I get at most 4 bars. I still detect him with enough time, but how do the state troopers turn their radar wattage down?

In NY, I have the same question with KA radar guns. I can pick up other cops with KA farther away, but not NY staties. WHY?????????

[thestaton]

Strength is proportional to effective range. So if you are picking it up miles away with your detector he's picking you up farther...

[jimbonzzz]

I would be one of those saying that. Different makes and models of units have different power output. Power is fixed and does not change when that range is adjusted. Output power is ultimately determined by the gunn diode in the radar unit, which has fixed power output. The only method to vary the output power would be to incorporate an electronically variable waveguide attenuator between the gunnplexer and antenna, and as far as I know this has not been done with any radar unit to date.

As far as what you are experiencing with NJ troopers, it is difficult to say. I thought that NJ troopers used MPH K55's. I would think at any rate, at 100 feet away, no matter what radar model you should get full strength on your detector. Are you sure the alert was from the cop, and there were not X-band motion sensors nearby?

The only other thing I can think of is they might have been using a handheld X-Band radar gun that was powered up, but laying on the seat.

Out of curiosity, what detector are you using? Maybe other New Jersey drivers can offer an explanation.

Jim

[Dilip]

Mr. Jim

I am also curious about radar power.

For example the multanova, its' manual shows that it has power settings to accomodate how many lanes to be covered. And in HK, on the same multanova, same location, same traffic conditions, sometimes i can get a lot of warning time and very strong signal, and sometimes no warning time and barely any signal. This would lead me to suggest that it's power output can be varied?

It's stated max power is 0.5mw, but could it be that on lower settings it only emits 0.1 or 0.2mw?

[Beeej259]

I have a 1.8 Pop2 valentine one radar detector. I'm sure he was using a dash mounted x band radar gun. This has happened to me many times before with NJ state troopers. I know it wasn't a motion detector because I picked him up from about 2 tenths of a mile out and the arrows immediately pointed to the sides and back when I passed him. But only 4 bars lit up. I have the V1 mounted right below the blue tint but above my rear view.

It would be interesting to measure the wattage output of police radar with some type of tool in the car. Jim, I know you own a couple radar devices, do you have any tools to measure the wattage put out by the gun when range is adjusted?

[jimbonzzz]

Mr. Jim

I am also curious about radar power.

For example the multanova, its' manual shows that it has power settings to accomodate how many lanes to be covered. And in HK, on the same multanova, same location, same traffic conditions, sometimes i can get a lot of warning time and very strong signal, and sometimes no warning time and barely any signal. This would lead me to suggest that it's power output can be varied?

It's stated max power is 0.5mw, but could it be that on lower settings it only emits 0.1 or 0.2mw?

Multanova might indeed be different in this respect, I don't know for sure but I wouldn't be surprised, as photo radar is a different application. I don't have any first-hand experience with photo radar.

Jim

[jimbonzzz]

I have a 1.8 Pop2 valentine one radar detector. I'm sure he was using a dash mounted x band radar gun. This has happened to me many times before with NJ state troopers. I know it wasn't a motion detector because I picked him up from about 2 tenths of a mile out and the arrows immediately pointed to the sides and back when I passed him. But only 4 bars lit up. I have the V1 mounted right below the blue tint but above my rear view.

It would be interesting to measure the wattage output of police radar with some type of tool in the car. Jim, I know you own a couple radar devices, do you have any tools to measure the wattage put out by the gun when range is adjusted?

I don't have any explanation for what you experiece, but I can tell you that under no circumstances should you be getting 4 bars with the V1 at 100 feet against any X-Band radar unit out there that I know of.

I don't have a method of measuring the output power, as the eqipment to do it at microwave frequencies is costly. Yes it might be interesting to do, but I still wouldn't expect the power to change at all. I have opened up many radar units, seen schematics and block diagrams for others, and none have included any mechanism for varying the output power. I have also spoken with people in the industry about this, and have been told the same thing.

So if any (US) radar units exist that have the capability to vary the output power, I sure don't know about it. If someone knows for sure that there are units out there like this and can provide me with some credible evidence, then enlighten me.

Jim

[Carlos from Spain]

Mr. Jim

I am also curious about radar power.

For example the multanova, its' manual shows that it has power settings to accomodate how many lanes to be covered. And in HK, on the same multanova, same location, same traffic conditions, sometimes i can get a lot of warning time and very strong signal, and sometimes no warning time and barely any signal. This would lead me to suggest that it's power output can be varied?

It's stated max power is 0.5mw, but could it be that on lower settings it only emits 0.1 or 0.2mw?

Yes, nominal power of the Multanova Ka band Photo-radar (Multanova 6F, 9F and 6F-MR) can vary from a minimum of 0.25mW to a maximun of 0.5mW.

But as Jim says, this is photoradar and its application is different,characteristics as these need not apply to both equally and should considered aside than normal radar.

Photoradars work at very close range since its target range is dictated by the digital camera's ability to capture the licence plate of the vehicles, and not the max range posible of the redar. Typically they are set to shoot at around 250 feet.

So they do not need much power and to avoid detection, they can set it according to the situation of the radar to be as tough to detect in anticipation by a radar detector as posible. I have encountered fixed Multanovas that even with the absolute best of the detectors for 34,3Ghz you won't get more than 100 feet advance warning at best.

[AirMoore]

I also have the exact same situation with 'k band' and the local campus police radar. We have 2 male campus police and 1 female (they all drive the same car...meaning well 1 is in the car, the other 2 are either walking around campus or at the security room). The campus police do visit the local PD since it is about 2 miles away rather often and they turn the radar on when they go on the roads.

The male campus police ALWAYS* leave the dashmounted k band unit on when coming in off the road...or just driving around campus (to make sure people are obeying campus speed limit.....whatever: point is they leave it on with the car parked. (Not sure what kind of radar) I will have to take a look. However the point is this...I cannot ever get a detection of over 200feet EVER! No matter what RD I have tried (literally 7) 5 of mine, 2 of my friends and No matter what there is NO 200foot plus detection... if I am at an angle to the car (more then 45 degrees) I have not ever gotten above '2bars', (even at less then 25 feet still not more then 2 bars) (or 1 out of 4 signal strength on the cheaper rds)....coming straight on it I have never ever gotten a full warning...I have literally parked across a little '5 foot median' from this thing...so about 8 feet away and still could not recieve a full signal (only tested 2 RD's with this).

MOST NOTABLE detectors out of the 7:My Passport 8500 (non-X50) which is famous for its great 'k' band detection (of its time) was one of the detectors I tested. Also the V1 (my friends) which has amazing k band protection even had problems (Detected it head on at what I would say was a max of 150 feet out of 4 times) with no obsticales I tried everything, nothing could help pick this radar up.

Thing is I know it isnt the RD's because the amount I tested, and my 8500 (non-x50) often gets well over 3/4mile warnings from constant on Cayuga County Sheriffs (Kband), and full alerts everytime (darn near) I pass one of their traps. So I cannot figure out why the RD's dont pick up the radar gun of the campus well. Can anyone tell me anything about this.

Anyone have any clues to why this would happen (Carlos/Jimbonzzz)?


AS for the original poster...I have never had that problem with any KA from NYSTroopers with any of my RD's or any RD's I have borrowed, They always pick up the signal if they NYST is using constant on far ahead of time. Honestly what you may be experiencing in that case is some nifty trigger work by some skilled NYSTroopers - we all know what I'm saying :twisted: - if you get no advanced warning when it comes to a trap (Not much an RD can do about that).

[Dilip]

Carlos: thanks for your information