Kiwi's XPS test results are up.

[GBR2]

It's amazing how post statements can come around to bite you in the a**. But wait, everything will be perfect again with the super firmware update.

[KrisW]

	Quote: Originally Posted by jonkoppisch
	Yep, he said it again. No mistake. xps does NOT hop if you encounter interference unless it shows up VERY slowly.... So if someone suddenly turns on a device that causes interference to xps it will not hop. You will be locked out!!! It's basically 1/2 of a spektrum system, a single channel unit. NO REDUNDANCY!!!! The was said all along (as when using the live video and xps locked out and didn't hop) and debated.. Now he's finally admitting to it. I can't believe how everyone still defends it... http://www.rcgroups.com/forums/showthread.php?t=872879 Quite a bit different than...

So . .let me get this straight. . .this was all some sort of horrible "Failure to communicate" ???



(pun intended. . . )

[spoiler]

I spent some time on the weekend reading the RCG XPS forum. It seems clear that XPS is using its customers as field test guinea pigs. They even ask for their input on design. Amazing...

[jonkoppisch]

More... Remember, you can't fly xps if there's WET GRASS OR HUMIDITY!!!

	Quote: Originally Posted by ozghost1952
	Flew in good sunny weather on Saturday - 4 flights with Raptor 90 practicing for Sunday competition. Typical run up to aerobatic manoeuvres is to fly as far out, perform stall turn and then fly back and forth along the flight line doing whatever – reason for mentioning – far distance – long range. On Sunday after completing the hovering manoeuvres – switched into idle up – and on the way out – heli went into failsafe (engine and pitch went low). Fortunately came back on air and managed to turn around and come back to land. What was different – only weather conditions – low cloud cover and light mist - pretty high humidity… Did all the usual checks – range was fine – battery tested OK – aerial connection fine. What should I be looking for? Can high humidity lower the range so severely? I was the only XPS at the field – rest of pilots flew out the day with no problems Regards Jeff

	Quote: Originally Posted by HarrisM
	It's quite possible that there was some condensation on your electronics (either Tx or Rx) and this may have caused the shorter range. This can happen even more easily if you keep everything in an air-conditioned car and then take it out and use it without allowing adequate time fo equilibration. It happened to a friend of mine a while back. He was on 35 MHz then.

& the ULTIMATE ADVICE...

	Quote: Originally Posted by JimDrew
	We have people buying our systems in record numbers due to crashes with our competitor's systems. I still believe setup is the biggest factor. Getting rid of switches, regulators, and the misc. junk that we seem to believe we need is the key to reducing unexplained problems.

So remember... You can't fly xps if you're using "switches, regulators, and the misc. junk" or if there's wet grass or humidity...

People are buying in record #'s... For a good ratio example.

	Quote: Originally Posted by hcopter
	I was just reading the SEFF thread about the world record setting flight of 100 models in the air at the same time. It says there were 59 Spektrum, 3 XPS and 2 Fasst systems flying, plus 40+ 72 mhz. The only ones that had any interference problems were 72 mhz and a couple of the first generation Spektrum. Really shows that 2.4 works pretty well in general and that Spektrum has a big market share. Wonder if any of the XPS guys had their XDP running and if they came back on a different channel than they took off on.

So that's 59 spektrum, 2 fasst to 3 xps....

Is it possible that we heard more about problems with spektrum because there are 29 spektrum radios to 1 xps flying???

[seattle_helo]

	Quote:
	the ULTIMATE ADVICE... Quote: Quote: Originally Posted by JimDrew We have people buying our systems in record numbers due to crashes with our competitor's systems. I still believe setup is the biggest factor. Getting rid of switches, regulators, and the misc. junk that we seem to believe we need is the key to reducing unexplained problems. So remember... You can't fly xps if you're using "switches, regulators, and the misc. junk" or if there's wet grass or humidity...

Oh man was that a great laugh. Thanks for posting that! Very, very funny... (and sad too)

nick

[jonkoppisch]

Ah, the latest claim is out...

	Quote: Originally Posted by JimDrew
	Joe Nall, SEFF, MWE, and other mainstream events had more XPS systems than FASST systems. Spektrum definitely has a lead, but they also had two years ahead of us with market share. We are getting numerous reports (and sales) from people who are crashing the competitor's systems and switching to ours.

More xps at Joe Nall than Fasst???? I highly doubt it!!!

http://www.rcgroups.com/forums/showt...80#post9877053

How about it kiwi? Were there more xps than fasst at Joe Nall???

[GBR2]

Wow, numerous reports.

[Flyfalcons]

Why does Jim only post in forums where he can delete others' posts?

[Kiwi]

Haaa. Delusions I´m sorry to say. There is no doubt that Spektrum has the market by the short and curlies but at the Nall there was a serious amount of FASST equipment in use as well. As to what the percentages were I would not dare even guess but to say XPS outnumbered FASST would have to be a serious stretch of the imagination. I mean there were more orange and black team guys in the crowd than I cared to count and they all ran FASST.

The second flight line was predominantly FASST and SPEKTRUM. I did not see any XPS units there but then again I was not doing a survey and counting antennas either.

The other comment regarding customers swapping away from SPEKTRUM and FASST due to crashes is just downright pie in the sky BS. Quiet the reverse I would say.

[Reckless Loony]

	Quote: Originally Posted by XJet
	But just as JD refused to provide the parameters -- the guys from Boeing have been strangely silent about *how* they got it to hop.

This is what JD wrote last year with regards to the hopping.

http://www.rcgroups.com/forums/showp...80&postcount=4

This is what Bruff wrote as one of the witnesses to this top-secret test.

http://www.rcgroups.com/forums/showp...0&postcount=89

http://www.rcgroups.com/forums/showp...7&postcount=93

	Quote:
	over a period of 11 seconds using a signal within +/- 15MHz of the XBeePro's center-operating frequency

This is just more crap. The reason that JD wrote that is purely to discredit Tyhoc and Kiwi’s tests.

The Xbeepro modules centre frequency range is 2.41Ghz to 2.465Ghz in 5Mhz steps page 38 of the user manual with regards to the CH command clearly points this out.

• First off 2.41GHz – 15Mhz is outside the 2.4Ghz ISM band and is outside the frequency that the Xbeepro can even go too.
• 15Mhz away is 3 channels away for the Xbeepro modules. What crackpot would get their system to go looking for signal degradation 3 channels away?
• The Xbeepro modules can only measure received signal strength. In order to be able to get any signal strength readings 3 channels away they would have to change channels and in so doing it would take a relatively long time during which there is no controlling signal being sent to the aircraft during the hop (channel changing) sequence.
• Frequently channel hopping around on a DSSS system is an idiotic stupid thing to do as the constant changing of channels will crash your aircraft and that is why the Spektrum system and Assan systems don’t even try to hop once they are locked onto a channel(s). Remember the Xbeepro modules are DSSS just the same as Spektrum and Assan.

Let me also make it very clear people that changing channels does not make up for lack of antenna diversity. That is why when you look at JD’s XPS install in his own turbine jet he has the receiver mounted high up in the canopy on a pedestal to try and keep the antenna maintain a line of sight to the transmitter and not get this blocked by that large turbine jet engine.

http://www.rcgroups.com/forums/showp...6&postcount=32

Just to make it clear the XPS system is the same as Assan X8 and Spektrum DX6 DSM (not the DX6i DSM2) park flyer systems.

[wrightme]

Huh?
http://en.wikipedia.org/wiki/ISM_band
"2.400–2.500 GHz (centre frequency 2.450 GHz)"
2.415 ghz is WELL within the ISM band range.

"within +-15mhz" is WITHIN the range of +3 or -3 channels, not beyond it.

	Quote: Originally Posted by Reckless Loony
	The Xbeepro modules centre frequency range is 2.41Ghz to 2.465Ghz in 5Mhz steps page 38 of the user manual with regards to the CH command clearly points this out. First off 2.41GHz – 15Mhz is outside the 2.4Ghz ISM band and is outside the frequency that the Xbeepro can even go too. 15Mhz away is 3 channels away for the Xbeepro modules. What crackpot would get their system to go looking for signal degradation 3 channels away? The Xbeepro modules can only measure received signal strength. In order to be able to get any signal strength readings 3 channels away they would have to change channels and in so doing it would take a relatively long time during which there is no controlling signal being sent to the aircraft during the hop (channel changing) sequence. Frequently channel hopping around on a DSSS system is an idiotic stupid thing to do as the constant changing of channels will crash your aircraft and that is why the Spektrum system and Assan systems don’t even try to hop once they are locked onto a channel(s). Remember the Xbeepro modules are DSSS just the same as Spektrum and Assan. Let me also make it very clear people that changing channels does not make up for lack of antenna diversity. That is why when you look at JD’s XPS install in his own turbine jet he has the receiver mounted high up in the canopy on a pedestal to try and keep the antenna maintain a line of sight to the transmitter and not get this blocked by that large turbine jet engine. http://www.rcgroups.com/forums/showp...6&postcount=32 Just to make it clear the XPS system is the same as Assan X8 and Spektrum DX6 DSM (not the DX6i DSM2) park flyer systems.

[easytiger]

	Quote: Originally Posted by Flyfalcons
	Why does Jim only post in forums where he can delete others' posts?

Because previously, when he was doing the EXACT SAME THING as he is doing now, slinging baloney, to sell paintball gear, he was on several boards, and he got "owned", as the kids say. There were too many people presenting too many facts that belied his claims, too many independent tests that showed he was a big ol' old fashioned liar. So he tried to take his ball and go home. On at least one site, he DEMANDED they remove all his posts or he would sue them. They refused. He also pulled the "I will spend a lot on advertising on your site if you just delete posts that are against me" thing, too. This stuff is all out there on the net.
RCgroups took his money, and are complicit in this whole thing. They can't feign ignorance, the owners knew Jim's past history, they were just "lucky" enough to get Jim's teeny advertising budget, and dishonest enough to be willing to be a partner in this unholy mess. They deserve whatever long-term loss of credibility they get from all this.

Hey, RCgroups: If you lay down with The Devil, sooner or later, you're going to hafta scr*w!

[easytiger]

All you guys debating the "frequency hopping" and talking about under what circumstances it MIGHT work, it's absurd. It does not work when someone turns on something on your frequency. That's it. Hence, it does not work at all. Like airbags that will only deploy at speeds over 175mph on your car. Yes, you have airbags. No, they don't do any good, no, you cannot hawk them as a safety feature.

The whole "hopping parameters" thing reminds me of that cartoon where Daffy Duck sells Porky Pig an insurance policy that will pay out one million dollars if Porky gets a black eye. But the fine print says that the black eye needs to be caused by a herd of wild elephants, on the Fourth of July, in a hailstorm, between 3:55 and 4:00pm only.
Oh, that fine print will get ya. See below? That's where Daffy is explaining the fine print to the fine print, it turns out it needs to be a herd of wild elephants AND one baby zebra(with a slowly rising noise floor?) to pay out...

[Reckless Loony]

	Quote: Originally Posted by wrightme
	Huh? http://en.wikipedia.org/wiki/ISM_band "2.400–2.500 GHz (centre frequency 2.450 GHz)"

	Quote: Originally Posted by wrightme
	2.415 ghz is WELL within the ISM band range. "within +-15mhz" is WITHIN the range of +3 or -3 channels, not beyond it.

I am referring to the operation of the Digi 2.4Ghz RF modules that JD uses in the XPS system. JD makes a claim of his XPS system and then I compare this claim against the Digi 2.4Ghz RF modules capability to see if they can do what JD claims of his XPS system.

A bit like me making the claim that my car can travel to the moon. But someone takes a peek under the bonnet where upon they discover that there is no rocket engine nor even life support. Therefore without the required hardware in place it is impossible for my car to even leave the ground let alone travel to the moon.

Now as to the frequencies the Digi 2.4Ghz RF modules use refer to the user manual here

http://ftp1.digi.com/support/documen...5.4_v1.xAx.pdf

Page 38 the CH (channel command)



The CH parameter range is 0C to 17 hexadecimal which in decimal is 12 to 23.

To understand the hexadecimal base 16 number system

http://en.wikipedia.org/wiki/Hexadecimal

Anyway the frequencies the Xbeepro 2.4Ghz operate on is given by

Centre frequency = 2.405Ghz + (CH – 11) x 5Mhz

Thus 2.405Ghz + (12 – 11) x 5Mhz = 2.41Ghz

2.405Ghz + (13 – 11) x 5Mhz = 2.415Ghz

2.405Ghz + (14 – 11) x 5Mhz = 2.42Ghz

and so on till

2.405Ghz + (23 – 11) x 5Mhz = 2.465Ghz

These are the only frequencies the Xbeepro RF modules can be switched too. Thus for the lowest frequency of 2.41Ghz if we now apply the JD BS of looking for noise 15Mhz away then 2.41Ghz – 15Mhz = 2.395Ghz which is outside the 2.4Ghz ISM band and further more on a frequency that the Xbeepro RF module can’t change too because the lowest frequency that the modules can be switched to is 2.41Ghz.

Say the Xbeepro RF module is on 2.435Ghz and you want it changed to 2.41Ghz and the Xbeepro RF module is connected to your PC via the RS232 port then using Hyperterminal which is part of windows XP you would type.



<cr> means hitting the enter key on the PC keyboard.

Saving to the Xbeepro’s non-volatile memory is only required if it is desired the next time the Xbeepro module is powered up it will default to 2.41Ghz.

[easytiger]

In other words, if someone turns on on your frequency, as millions of devices out there can do, you will get shot down?