MAJOR 2.4 Ghz Spread Spectrum Release! A FlyingGiants Exclusive!

[Robin]

Hi fellas, I've a question for you who know how this system works. The transmitter scans for two free channels then locks on to them. If so the Tx must have a reciever of some sort built in, yes?
Ok so at an event on a large airfield where several groups are flying, then its possible for the most distant txs to be almost two miles apart on the ground.
Not good for the scanning me thinks, I'm sure you kn ow what I'm getting at so can anyone put our minds at rest please?
cheers
Robin

[pda4you]

	Quote: Originally Posted by Robin
	Hi fellas, I've a question for you who know how this system works. The transmitter scans for two free channels then locks on to them. If so the Tx must have a reciever of some sort built in, yes? Robin

http://www.spektrumrc.com/Articles/...eID=1535&Page=1

The element you are missing is the GUID code. Each Spektrum transmitter has a GUID (Globally Unique Identifier) code. When you perform the binding process it links the RX and TX together. The RX then only takes the signal of the transmitter it is bound to. So it will only listen to the TX is is supposed to. I think there is something like 4.2 billion GUID codes so your chances of having a interference from another transmitter on the exact two channels you are using with the exact same code is numberically impossible.

I have been using the DX6 and DX7 since both were released - never an issue, including testing that I intended to cause issues......with other 2.4GHz devices. I have sold all my 72MHz stuff now - I am that convinced.

Mike

Mike

[OverTemp]

	Quote:
	I think there is something like 4.2 billion GUID codes so your chances of having a interference from another transmitter on the exact two channels you are using with the exact same code is numberically impossible.

I don't know about that! If every man woman and child on earth had 2 Spektrum radios and they were all turned on at once within a 3 mile radius then we might see some real problems here... wow I'm a little worried now. I wonder if Spektrum has addressed this?

[All Thumbs]

Forget all the "women"... There, problem addressed!

[FLYNYAK]

I have watched this post from the beginning and want to add my 2 cents.

I for one will dump all my 72 MHz as soon as I can get a 2.4 SS for my JR 9303.
I have used the DX 6 since day one of its release for my fomy's and small heli's.

OK say Im at my flying field flying my pride and joy. which my flying field is right next to a office building full of cordless phones, 2.4 MHz phones all are being used buy people all day . I would rather have 2.4 SS than a 72 MHz because of the one jerk with a park flyer on 72 who shows up to fly in the parking lot of the office building . There is more of a chance in being shot down or just interfered with, buy just the off chance that a unknowledgeable person with a 72 MHz transmitter turns it on near me, than being interfered by somthing else on 2.4.
2.4 SS may not be 100 perfect but it is much better than 72MHz in my eyes.

And when it comes to fail safe programing let me have a shot to try to explain it better for the guy a few posts back. Yes there is a fail safe that you can make your throttle go to a preprogrammed position. but not buy the program in your radio that you are using know.
It is done when you bind the reciver to your radio.

[Robin]

Thanks, I'm happy with the GUID and how it should work. My concern is related to how the txs scan and lock on to the two free channels, GUID aside if sufficient txs are in close proximity then the channels would get taken up and at some stage a tx will not find any channels free. So how does the tx sense, see, hear, recieve the transmissions from other txs?
IF this is how the system works then obviously there is a range beyond which one tx will not be able to pick up the other dutring its scan, and therefore could decide to use the same channel/channels as another tx not too far away. Bearing in mind the txs are on the ground, line of sight and all that, whereas the rxs are obviously going to be up above and able to receive from both these hypothetical txs. OK GUID means mine will only listen to me BUT could this cause a lock out?
OK its unlikely, however.....
The scenario I'm thinking of is a large event at an airfield, lots of different disciplines flying with up to say two miles or so of terrain between txs ie the UK nationals.
By the way I think the kit and technology is fantastic, definitely the way ahead.
I'm simply looking for peace of mind here!
cheers
Robin

[pda4you]

	Quote:
	Bearing in mind the txs are on the ground, line of sight and all that, whereas the rxs are obviously going to be up above and able to receive from both these hypothetical txs. OK GUID means mine will only listen to me BUT could this cause a lock out?

Robin - you worry too much! Go fly....

No issues - I have flown with numerous (20+) other 2.4GHz devices - outside, inside we just can't get the Spektrum systems to glich, hit or bump. Not one single time....

The systems work, and work reliably, more so than any previous radio system I have used.....

Mike

[DesertHucker]

	Quote: Originally Posted by Robin
	Thanks, I'm happy with the GUID and how it should work. My concern is related to how the txs scan and lock on to the two free channels, GUID aside if sufficient txs are in close proximity then the channels would get taken up and at some stage a tx will not find any channels free. So how does the tx sense, see, hear, recieve the transmissions from other txs? IF this is how the system works then obviously there is a range beyond which one tx will not be able to pick up the other dutring its scan, and therefore could decide to use the same channel/channels as another tx not too far away. Bearing in mind the txs are on the ground, line of sight and all that, whereas the rxs are obviously going to be up above and able to receive from both these hypothetical txs. OK GUID means mine will only listen to me BUT could this cause a lock out? OK its unlikely, however..... The scenario I'm thinking of is a large event at an airfield, lots of different disciplines flying with up to say two miles or so of terrain between txs ie the UK nationals. By the way I think the kit and technology is fantastic, definitely the way ahead. I'm simply looking for peace of mind here! cheers Robin

If it makes you feel better the rx can comunicate bi directional to the TX, and i would believe it would only change 1 channel at a time. So you would always have coms.