Kiwi's XPS test results are up.

[jonkoppisch]

Kiwi, Thanks for coming threw with the testing!!!! & sorry about all of the headaches.... Look forward to the other tests especially as I'm running Fasst now!

Added: Not that's what I call a 'Busted' thread!!!!

[Boulder]

Great job Allan, I expected nothing less

[Pale Rider]

Kiwi--which system is up next for testing ?

[klhoard]

	Quote: Originally Posted by Julez
	. . .<snip>. . 0V: nothing happens . . .<snip>. .

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That is why I'm an XPS fan, Futaba just gives up at 0V . . . .
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[zoomer260]

	Quote: Originally Posted by Julez
	Concerning low voltage in the TX: A german user tested his 7C Fasst system: http://www.rc-network.de/forum/showp...7&postcount=50 8.5V: TX starts beeping. 4V: Module stops transmitting, LEDs go out. 3V: Display goes blank, TX stops beeping. 1.5V: red LED on TX goes out. 0V: nothing happens Now Battery is slowly recharged, still connected to TX: 3V: display comes to life, TX beeps 4.5V TX starts transmitting again, and RX LED changes from red to green. So everything above 5V should be pretty safe...

I find this very interesting ! It never occured to me to fly a Transmitter below 9.6 volts. I always gave it a bump with a field charger. Is this not needed ? What is the voltage that most get nervous with ?

[Al Czervik]

Kiwi,

Thanks for taking the time to do the research and to post it. Probably the biggest asset of the internet is the exchanging of information and this is a perfect example.

I'm hoping like hell the FASST 8 channel gets here in the states before too long. I have one XPS receiver and transmitter left..and using XPS is a gamble until I can move on to Futaba.

[treb63]

Hi,
I'm sorry if this seems a little confrontational but, I have made/seen XPS system swap channels so to say it catagorically doesnt change/swap is absolutly not true, the manner in which it swapped channels may not be particullarly useful or predictable but swap/change it did, now if only I could get video I would be a bit happier and I guess the point of this thread would be somewhat mute.

How the swap/jump occured was during some testing in my hanger/workshop, I had my XPS system in a MC24 transmitter linked to a 8 channel receiver in a model less than 6 feet away with no aerial on the MC24, the enviroment had all the usuall slight background noise which could be assosiated with a typical housing estate ie routers ect I also had the XPD frequency analiser programme running on my laptop in the workshop which showed my TX on channel 10.
A friend who had just bourght a Futaba FAAST module for his 9 channel Tx switched on his TX which showed a lot of increased activity on most frequencys/ channels although not quite as strong as the channel 10 XPS one. He then put his aerial of his TX on the XPS receiver aerial during this time I still had complete control of all servos in the model with no glitching or lockout although there was a slight increase in buzzing from all of the servos?
He then switched of his transmitter and when we looked at the XPD analiser it showed a strong signal now on channel 20 which dissapered when I switched off my MC24 and receiver there was no signal at this time on the original channel 10.....
On switching back on the MC24 and receiver it again showed signal on channel 10.. (swapped back/ default?)

This may not have been a acurate test using state of the art test equipment or in fact a repeatable test (not tried again as of yet) it may not even jump if the same criteria was followed, it may even not be a usefull test as his Tx aerial was touching my receiver, however Jump/change it did.

Wether the system will ever jump in practical use in the field is not established, but I belive there are a lot of other issues with XPS and its practicality at the moment which make the jumping issue less important.

Regards

[KrisW]

	Quote: Originally Posted by treb63
	Hi, I'm sorry if this seems a little confrontational but, I have made/seen XPS system swap channels so to say it catagorically doesnt change/swap is absolutly not true, the manner in which it swapped channels may not be particullarly useful or predictable but swap/change it did, now if only I could get video I would be a bit happier and I guess the point of this thread would be somewhat mute. How the swap/jump occured was during some testing in my hanger/workshop, I had my XPS system in a MC24 transmitter linked to a 8 channel receiver in a model less than 6 feet away with no aerial on the MC24, the enviroment had all the usuall slight background noise which could be assosiated with a typical housing estate ie routers ect I also had the XPD frequency analiser programme running on my laptop in the workshop which showed my TX on channel 10. A friend who had just bourght a Futaba FAAST module for his 9 channel Tx switched on his TX which showed a lot of increased activity on most frequencys/ channels although not quite as strong as the channel 10 XPS one. He then put his aerial of his TX on the XPS receiver aerial during this time I still had complete control of all servos in the model with no glitching or lockout although there was a slight increase in buzzing from all of the servos? He then switched of his transmitter and when we looked at the XPD analiser it showed a strong signal now on channel 20 which dissapered when I switched off my MC24 and receiver there was no signal at this time on the original channel 10..... On switching back on the MC24 and receiver it again showed signal on channel 10.. (swapped back/ default?) This may not have been a acurate test using state of the art test equipment or in fact a repeatable test (not tried again as of yet) it may not even jump if the same criteria was followed, it may even not be a usefull test as his Tx aerial was touching my receiver, however Jump/change it did. Wether the system will ever jump in practical use in the field is not established, but I belive there are a lot of other issues with XPS and its practicality at the moment which make the jumping issue less important. Regards

Actually FASST would be avoiding whatever channel you were on, like it was the plague, so the test only shows that your XPS system was not interfered with by a system that was AVOIDING it in the first place. The reason for your servo's buzzing was probably because you were just blanketing the entire receiver with RF energy, and every part of it was getting hit by energy it was not designed to withstand in the first place. Kind of like putting an old drill next to an AM radio. You still hear the radio, but the output amplifier is being jinxed by the drills stator windings sparking against the brushes, so you hear that noise as well. The servos were getting pulses at whatever PRF the FASST was transmitting, probalby 100 pullses per second. . no WONDER they were buzzing.

As for something coming up on channel 20, does XPS evern transmit on channel 20? I thought it had 12 discrete channels to choose from, and if that is so, your RF signature on channel 20 could not have been the XPS unit in action. The fact that on powering back up you had an instant signal on ch10 means that the TX and RX never left the channel, and rebooted right to the channel they had been linked on before. Since XPS re-boots on the last frequency it was on, if the XPS system had actualy switched over to ch20 (which I do not think it can even do), then it is logical to presume that the system would have rebooted back onto that channel (channel 20) instead of going back to the channel it had supposedly left (channel 10).

All I see here, from what you relate, is that the XPS was not interfered with by the FASST, simply because the FASST avoided the channel XPS was on. . . that the servos and output section of the XPS receiver was swamped by the PRF of the FASST system, causing an anomaly on the signals sent to the servos, and causing them to buzz as they tried to compensate for the energy on top of the signal from the XPS receiver .. . and third, given that the reboot went back to ch10, and XPS tends to go back to the channel it last had, the XPS unit NEVER left ch10 in the first place. Where the signal for ch20 came from is a mystery, since XPS supposedly cannot even transmit on that channel.

[treb63]

Hi Kris,

I certanly agree with the servos buzzing was probably due to the whole receiver getting 'hit' just imagine what would have happened if this were a good old FM set up!

However a few of things to note,
1.there was no peak at channel 20 before the test.
2.there was no peak at channel 10 after turning the Futaba set off despite having full control of the model this was left scanning for over a minute with no show on 10.
3.Channel 10 was showing just the same trafic as all the rest while the Futaba set was on. (I think that the Futaba set was transmitting on 10 as the peak was moving the same as all the rest.)
4.the peak at channel 20 disapered the moment the MC24 transmitter was turned off.
5. if it makes a difference? this was an european spec' Tx module and a US spec receiver?

Not iron clad I'm sure however not easy to see what else could of happened given the above except but a jump occured.
regards

[treb63]

Oh one other thing which may be a point to mention,
The MC24 didnt have an aerial connected but the Futaba did, the strength of the MC 24 transmission was just as high as the Futaba, ie the source of the background noise was at least as strong as the transmission itself probably more so regarding the proximity of the aerials.
Regards

[ricoalonso]

	Quote: Originally Posted by KrisW
	<snipped>... As for something coming up on channel 20, does XPS evern transmit on channel 20? I thought it had 12 discrete channels to choose from, and if that is so, your RF signature on channel 20 could not have been the XPS unit in action... <snipped>.

Good point... either 12 or 16 channels. Can someone familiar with XPS hardware (ie: Xbee) check and confirm this? Is it capable of going to that Channel?

Thanks.
^R^

[treb63]

Ive just read in another thread that someone has his XPS on channel 50 on the XPD analyzer programme?