Independent tests prove lack of frequency hopping with XPS

[XJet]

	Quote: Originally Posted by RichardCorby
	AMEN TO THAT!!!!!!! If you can't say somethin' good - Don't say nuttin!!

What a great idea -- let's hide our heads in the sand because we don't want to know the facts about anything.

How dare Ford or Chevy issue a recall when they discover a major fault in the brakes on their 2008 model -- if they can't say somethin good they should keep their damned mouths shut -- right?

Come on Richard, sensible people want to know what the strengths and limitations of the technology are even if you don't.

I would suggest that if you don't want to hear anything bad, you unsubscribe from all threads that have anything to do with RC technology because (since it's stuff designed and built by man) there are always going to be bad-news stories involved at some time or another.

[Flatlandman]

I took RichardCorby's comment to mean- if you dont have anything productive to say dont say anything-. This ideal I like a lot!

[Pale Rider]

	Quote: Originally Posted by Flatlandman
	I took RichardCorby's comment to mean- if you dont have anything productive to say dont say anything-. This ideal I like a lot!

Me too

[XJet]

	Quote: Originally Posted by Flatlandman
	I took RichardCorby's comment to mean- if you dont have anything productive to say dont say anything-. This ideal I like a lot!

If I misinterpreted his comments then I apologize.

[Flatlandman]

Im sure you didnt mean any thing by it; thats just the way I saw his comment. A lot of the time my diction doesnt match my meaning. It happens a lot on the net.

[JimC-MD]

OK XJet. Here it is STRAIGHT to YOU. What are the rules for 2.4 use? Does that video system you are saying knocks out the XPS conform to standards for 2.4? I am talking in the US. That is where I am so that is what I care about. Are there standards for 2.4? What are they? Do you know? If you do not and can provide us with no references I am through with this thread.

Hope you all would understand why.

GDay

[USN_POPS]

Wow!!! I'm getting scared to death of this radio control stuff. Nothing is going to save my investments in aircraft etc. All the technology is bad stuff. So I think I better give up this hobby that I've participated in for 40 plus years, and take up something safer.

Maybe knitting. Unless I stick a needle in my eye I should be safe.

[XJet]

	Quote: Originally Posted by JimC-MD
	OK XJet. Here it is STRAIGHT to YOU. What are the rules for 2.4 use? Does that video system you are saying knocks out the XPS conform to standards for 2.4?

What difference does it make?

If a commonly available 2.4GHz video transmitter (of which there are many thousands (or perhaps tens of thousands) sold and used world-wide every year is able to take out a system in the way I've observed, it's not really relevant if it's rule-compliant or not.

Walking up to some poor flier who's left with a pile of smoldering wreckage as a result of being shot down and saying "it must have been an illegal transmitter" isn't going to put that bird back together, replace the engine or restore a life that may have been lost if it took someone out on its way to oblivion. This is especially true if those flying FASST and Spektrum/JR continue to fly, apparently unaffected.

While it might be nice to dwell in a world where everybody lives by the rules and all the relevant standards are rigidly adhered to I think we have to be a little more pragmatic when large amounts of money and human lives are involved.

If someone's weighing up the various 2.4GHz options I think it's a safe bet that they'll be more likely to opt for a system that shows the highest-level of resistance to legal (and illegal) interference -- or have I got that wrong?

This is why we need some objective, comparative tests which subject each of the available 2.4GHz options to a range of controlled conditions designed to measure their resilience to variouis forms of interference. Having access to this information can only be a good thing.

	Quote:
	I am talking in the US. That is where I am so that is what I care about. Are there standards for 2.4? What are they? Do you know? If you do not and can provide us with no references I am through with this thread.

There are standards for 2.4GHz -- although they do tend to vary somewhat in different countries (namely power, spectral density, etc).

The point you raise however -- in respect to the legality or otherwise of an interference source, makes it very clear that one would be silly to rely on having those "standards" protect you. They won't stop you being shot down.

Just talk to JD about the numebr of completely legal 2.4GHz sources that can adversely affect all 2.4GHz systems (including XPS). There are definitely flying fields around where *legal* 2.4GHz traffic has made model-flying on this band either impossible or decidedly unwise.

So clearly, even when the standards are rigorously adhered to, there's no guarantee that a system won't be shot down -- simply because 2.4GHz is a bit of a "wild west" band where, so long as you adhere to the few rules there are, it's pretty much "every man/device for him/her/its self."

Although the goal is to ensure that all 2.4GHz equipment "plays nicely with others" the permutations of possible combinations has already reached the point where any practical proof is a physical impossibility.

[USN_POPS]

Xjet:

We have an old saying here in the Western US that dates back to the old Cowboy days.

"Theres no sense beating a dead horse"

So now that you have beat this subject to a quivering pulp please live up to another old saying.

"Leave sleeping dogs lie"

I just returned from flying maiden flights on my ACE 4-4o Bipe and 6 flights on my 4 year old EP Superstar with not a glitch on the XPS system. So quit trying to burst my bubble.

In my case perhaps another old saying applies. "Ignorance is Bliss"

[JimC-MD]

	Quote: Originally Posted by XJet
	What difference does it make? If a commonly available 2.4GHz video transmitter (of which there are many thousands (or perhaps tens of thousands) sold and used world-wide every year is able to take out a system in the way I've observed, it's not really relevant if it's rule-compliant or not. Walking up to some poor flier who's left with a pile of smoldering wreckage as a result of being shot down and saying "it must have been an illegal transmitter" isn't going to put that bird back together, replace the engine or restore a life that may have been lost if it took someone out on its way to oblivion. This is especially true if those flying FASST and Spektrum/JR continue to fly, apparently unaffected. While it might be nice to dwell in a world where everybody lives by the rules and all the relevant standards are rigidly adhered to I think we have to be a little more pragmatic when large amounts of money and human lives are involved. If someone's weighing up the various 2.4GHz options I think it's a safe bet that they'll be more likely to opt for a system that shows the highest-level of resistance to legal (and illegal) interference -- or have I got that wrong? This is why we need some objective, comparative tests which subject each of the available 2.4GHz options to a range of controlled conditions designed to measure their resilience to variouis forms of interference. Having access to this information can only be a good thing. There are standards for 2.4GHz -- although they do tend to vary somewhat in different countries (namely power, spectral density, etc). The point you raise however -- in respect to the legality or otherwise of an interference source, makes it very clear that one would be silly to rely on having those "standards" protect you. They won't stop you being shot down. Just talk to JD about the numebr of completely legal 2.4GHz sources that can adversely affect all 2.4GHz systems (including XPS). There are definitely flying fields around where *legal* 2.4GHz traffic has made model-flying on this band either impossible or decidedly unwise. So clearly, even when the standards are rigorously adhered to, there's no guarantee that a system won't be shot down -- simply because 2.4GHz is a bit of a "wild west" band where, so long as you adhere to the few rules there are, it's pretty much "every man/device for him/her/its self." Although the goal is to ensure that all 2.4GHz equipment "plays nicely with others" the permutations of possible combinations has already reached the point where any practical proof is a physical impossibility.

NOW we are getting somewhere.

If you want to blast a system for not having a robust enough link under adverse conditions, that is fine. We should understand how these sytems work and make choices based on that. But the "What do the rules matter" attitude does not fly with me. I will give you and example and see if you can grasp it. Remember the days when we went from wide channel to narrow channel spacing on 72? Basic halving of the Tx Rx signal to fit twice as many channels. Existing radios had to be checked and tuned to operate under the new rules. If someone came out with an obsolete Tx or a system that was mistreated and out of tune and they shot another Rx down, what do we have? Was the radio in the killed airplane junk and subject railings of people from all over? HELL NO. It was the fault of the crappy radio that was not doing the right thing. I am saying that if the issue is the crappy video systems not working by the rules THEN THEY NEED TO GO! and we need to improve the robust quality of our links...... Do you see the distinction here? What is the cause DOES matter. Improvements are always good. Tell the whole story and let people become informed

These discussions are so much like politics it really gets old. Half truths and spin. Everyone has a paradigm and sees things through a filter. I applaude people that look into things. Like seeing the information. Just realize that people will look at what you say and how you test and say, "what about this?" That is a good thing in the part of the US that I come from.

It is called learning and peer review and BS filtering. If it stands the test, all the better.

[1bwana1]

	Quote: Originally Posted by RichardCorby
	Wow!!! I'm getting scared to death of this radio control stuff. Nothing is going to save my investments in aircraft etc. All the technology is bad stuff. So I think I better give up this hobby that I've participated in for 40 plus years, and take up something safer. Maybe knitting. Unless I stick a needle in my eye I should be safe.

Richard,
Have you ever thought of flying control line? You won't get shot down.

[XJet]

	Quote: Originally Posted by JimC-MD
	NOW we are getting somewhere. If you want to blast a system for not having a robust enough link under adverse conditions, that is fine. We should understand how these sytems work and make choices based on that. But the "What do the rules matter" attitude does not fly with me.

I still argue that if you find yourself staring at a pile of busted balsa, ply and fiberglass that used to be a giant scale model, you're not going to get any comfort from being able to attribute it to some unknown party who must have broken the rules.

Much better that someone did the tests and warned you that the gear you're using (whatever it is) may be deficient in some way that could make you more vulnerable to such interference.

Basically, if we could simply rely on folks to follow the rules we wouldn't need seatbelts or airbags because nobody would ever fail to give-way at an intersection, pass on a dangerous bend or drive while drunk.

But hey, we're pragmatic enough to realize that "better safe than sorry" is the best attitude on the roads and so it should be with RC gear.

If you choose to drive without belts or bags and have a smash, I don't think the fact that the other driver was drunk will provide any practical consolation if you're left facing life in a wheelchair.

As I've said all along, we need some objective tests and comparisons of the various 2.4GHz systems so we know how each handles a set of well-designed situations that may occur either as a result of "legal" or "illegal" interference.

What's wrong with that?