i actually agree with this guy :shock: but v1 reliability started to slip with the new revisionsOriginally Posted by richardboy316
|
|
|
|
|
i actually agree with this guy :shock: but v1 reliability started to slip with the new revisions
My comment removed for redundancy
My comment removed for redundancyIf the RX65 alerted 2-3 secs (161.333 - 241.999 feet) prior to the v1 @ 55mph, that is 484-726 (NOPE!) feet before the v1, so yeah, roughly 1/10th of mile as Ace said. At 70mph, a car travels 308 (NOPE, 102 FPS) feet per second, which means, assume that both RD's would've alerted at the same distance at the prior speed, it would've alerted probably around 1.5-2 secs prior to the v1. So, lets say for every 10-15mph over the speed limit, the RX65 loses a second of advance warning over the v1.
Does it still alert quicker? Of course.
But, at highway speeds, such as 80-90, is it a big difference?
Of course, I know there is probably a lot of fault in this logic, such as this test result was because of a curve not found at highway speeds of 80-90... but... it was fun doing the math nonetheless
Feel free to rip my dissertation apart!
Here's a velocity converter for you LINKY
My comment removed for redundancy
And in my sig, click the blue word "here" for a speed reduction chart, Showing the average times and distances from a given speed to the PSL.
This post has been edited by the author, removing redundant comments pointing out the errors already explained by others.
I said this in my first post, but it was rather long so I will say it again. NO. I put one detector up and then went by the CHP. Then while at the red light waiting to make a U-turn I took that down and put the other one up in the same place as the first one. Same height too. So both had the same level play field as the other.
Ace
thanks oakhed, but someone else beat you to pointing out what an idiot i am.
Well I think it would be nice if there was a way to combine all the favorite features such as friendly user interface, easy to use for the beginner yet fun enough for those of us who are "advanced" and talented. Say for example, the arrows from the V1, the expert mode from the X50, the voice alerts from the 65, and the stelath from the Sti. Combine all of them into one with the strongest detection range from each detector (i.e. the laser from V1, KA from 65, K from X50, and so on) Creating the best detector yet. It wouldn't be perfect but at least a vast majority of us could agree on! SO who is up to the challenge!
Ace
hoenstly does two detectors at the same time matter if they arent mounted next to each other
Im just a Mechanical Engineering student that just absolutely LOVES his Math
when I see wrong equasions I just have a habit of trying to correct um
I agree, that small bit of time isnt TOO terribly big a deal.......but it does help..........I mean it cant hurt right??
Oh yea
Absouletly,
Because even if you don't get a (for example) K band false as soon as you turn on the other detector. It can still do some pretty nasty internal and unnannounced (no warning) damage to one or both detectors. Such as abliterating (sorry for bad spelling!) the range causing both detectors to not alert to anything even if the souce was smack dab in front of it. OK maybe not that bad but hopefully you get the point.
Ace
Nice try but it means nothing!
Your testing and results mean nothing if you had both the RX65 and V1 running at the same time!!
http://valentine1.com/lab/DoItYourself.asp
First Problem: Detectors hate each other - Every superheterodyne receiver—that includes all of today's radar detectors—receives and transmits during normal operation. As you probably know, these detector signals sometimes set off other detectors. Out on the road, other detectors are the most common nuisance signal V1 has to deal with.
What's not so obvious is this. Even if a detector isn't set off by another one, it's internal defense system maybe be affecting its radar sensitivity. This problem compounds when you bring two operating detectors into the same car. Up close, the transmitted signals become much stronger than a normal design would anticipate, and the weak signals that wouldn't bother at normal distances can send the defense system into hyperdrive.
V1 inspects every signal it receives and decides, Is it really radar? Is it maybe radar? Is it not radar. But it isn't designed to operate within a few feet of another detector, and we know of no other detector designed for that high-stress condition either.
Here's the irony: If you put two detectors together and one of them seems sluggish, you might decide that one is inferior. In fact, it may have a superior defense system, and the detector that appears to work better may be a grotesque polluting transmitter.
http://guysoflidar.com/twodetectors.html
Why it's a Bad Idea to Run Two Radar Detectors in the Same Vehicle
--------------------------------------------------------------------------------
Just because two detectors don't set each other off doesn't mean that they arent interfering with each other. Here are a few resons why you shouldn't run two together in the same vehicle.
It Could "Fool" the False Alert Filtering
Many people familiar with detectors know that false alerts can sometimes be caused by other detectors operating nearby. What is not so obvious, is during their regular sweep, most detectors are also scanning for other non-police radar frequencies that, if detected, could BLOCK or PREVENT an alert.
Superhetrodyne radar detectors contain "Local Oscillators" (or LO for short). LOs create a radar signal that is utilized to "mix down" the incoming radar signal for detection. Although the LO is only used inside the detector, in many cases because of the design etc the LO is actually "leaked" or "transmitted" from the radar detectors (this is the signal RDDs detect to know if a radar detector is being operated) Many detectors on the road have a 1st LO that operates in the 11-12 GHz range. The problem is, that these LOs also produce "harmonics" at multiples of the LO frequency. So, in once classic example, an LO operating at 11.55 GHz would produce a harmonic at 34.65 GHz.
This poses a problem for detector makers. They need to suppress false alerts from other detectors, while allowing real police radar through. So here's what they do: they take advantage of the fact that if another detector is producing a 3rd harmonic harmonic in the Ka band, the fundamental or 2nd harmonic will also be present. But with police radar, no harmonics with these characteristics would be present, since the fundamental frequency of these is in the Ka band.
So, per the above example, if Ka radar was detected at 34.7 Ghz, the detector would also check the LO fundamental at 11.558 GHz, or the second harmonic at 23.116 Ghz. If one or both of these were present, the detector would know that the Ka radar was a false harmonic from another detector and would suppress the alert. So in addition to looking for police radar, most detectors also look for these LO frequencies or ther second harmonics. If the LO frequency, the 2nd harmonic, or both are present. they can tell that the detected radar signal is not police radar and can suppress the false alerts from other detectors.
So, what if a leaky detector is nearby at the same time as police radar is?
Some of the high-end detectors also put fail-safes in place for this: they will examine the signal levels of the harmonics and the Ka radar. If the Ka signal is much stronger than the harmonic, the detector will alert anyway, just to be safe. This works great, except when another detector is operating in the same vehicle. Because the two detectors are close to each other, if one detector sees a harmonic from another, that harmonic will always be strong compared to any real police radar that is detected.
In some cases, the harmonic doesn't even need to be detected at the same time as the Ka radar for the alert to be suppressed, as long as it falls into a "time window" specified in the detector's software.
The whole thing gets pretty complex:
-there are countless frequency schemes used by different detectors, in addition to the 11.55 GHz example above.
-the oscillators are sweeping
-the oscillators in some detectors will "park" to get a closer look at suspected police radar.
All it takes for one detector to suppress a Ka alert on another is for the wrong frequency from the other detector to be detected at the wrong time.
It might cause a detector to "park" often during it's sweep
Some detectors operate by sweeping quickly to look for police radar, and when they see a signal, they "park" their LO to get a closer look at the signal to see if it is really police radar. With another detector operating in close proximity, it might see leaked oscillator interference from the other detector and "park" on different frequencies in order to get a better look. Even if it determines that it isn't police radar that caused the "park" and suppresses the alert, it will still have the effect of unnecesssarily slowing down the overall sweep, reducing the effectiveness to real police radar. This can be especially critical to POP performance.
It could raise the "noise floor"
With a microwave oscillator operating in close proximity, it likely raises the "noise floor" in different bands. The detectors use singal averaging between multiple sweeps to identify a threat-level signal, so raising the noise floor would have the effect of making it so that a stronger signal would be necessary for the detector to be able to pick out radar signals from the noise.
Even enclosing the detectors in metal isn't going to prevent this, since a lot of the leakage comes from the antenna.
It might be OK on some bands/frequencies but not others, it might work just fine until the sweeps of the two detectors coincide with each other in a certain way. But there's just no way to be sure when it is a problem and when it isn't.
You'll hear some people say that they've done run two together for a long time with no problems, but how do they know for sure?
So bottom line: to be safe, don't run two detectors in the same vehicle, especially if you are comparing performance.
-jimbonzzz
Posting Permissions
Reply With Quote
Bookmarks