2.4Ghz
#1
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I have a Futaba Fast 2.4Ghz radio. I noticed many houshold objects use 2.4Ghz to communicate ie(phones, wireless doorbells, advanced walkie talkies, and live feed wireless cameras) I was wondering if any of these objects will interfere signals with my plane. I don't want to crash because someone picks up the phone in a local neighborhood. 
Electrolight

Electrolight
#4

Household phones are very low in pwr and operate on set channels
different from rc also the rc radios are designed to deal with the
occasional interfernce they may encounter.
different from rc also the rc radios are designed to deal with the
occasional interfernce they may encounter.
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I understand that the Federal requirements for the design of all those devices has a stipulation that every one must absolutely reject interference from all others to the extent that their specified purpose be completely secure. That's why we have the operating strategies we have. One of our systems switches frequencies faster than our radio systems tell all the servos what we want them to do. That way, if any slice of information happens to hit anything like interference on a frequency, the information transmission will be using a new frequency so fast, that the little slice that was bad won't have been large enough to cause the airplane any problem at all.
That's the spin on it anyway.
That's the spin on it anyway.
#7
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i'm a futaba 2.4Ghz user and while setting up my planes at the house, the only negative to having any of my 2.4 devices on is it takes a bit longer for the Tx to link up..........but after that it's rock solid.............if i unplug my router it cuts the link time by 75%. to test things out though, i have unplugged and then replugged the router, phones, etc.............and no problems encountered.
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I'm considering the new [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LNSBX0&P=G]Futaba 7C 2.4GHz[/link]. From time to time I think "Maybe Ill just stick with 72MHz" because I fear that the new technology is not as robust as one would like. Not many people at my field have 2.4GHz but so far I've witnessed 3 big crashes due to incorrect antennae installation in the Rx. This is one of the main reasons that makes me want to remain using 72MHz. Am I just being paranoid, or should I still consider 72MHz over 2.4GHz?
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ORIGINAL: plugin
Not many people at my field have 2.4GHz but so far I've witnessed 3 big crashes due to incorrect antennae installation in the Rx. This is one of the main reasons that makes me want to remain using 72MHz. Am I just being paranoid, or should I still consider 72MHz over 2.4GHz?
Not many people at my field have 2.4GHz but so far I've witnessed 3 big crashes due to incorrect antennae installation in the Rx. This is one of the main reasons that makes me want to remain using 72MHz. Am I just being paranoid, or should I still consider 72MHz over 2.4GHz?
now to really see what would happen with the antenna installed incorectly, we taped the 2 antennas together and routed them back under the reciever and servos.............still got the same range.
there are several other flyers at our club that are using Futaba and JR, and no one has had one problem yet.....not even a hiccup.
and again, the nice thing is, when you are up in the air, you have no worries about someone switching on and shooting you down.
so yes, you are paranoid.
#10

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ORIGINAL: da Rock
I understand that the Federal requirements for the design of all those devices has a stipulation that every one must absolutely reject interference from all others to the extent that their specified purpose be completely secure.
I understand that the Federal requirements for the design of all those devices has a stipulation that every one must absolutely reject interference from all others to the extent that their specified purpose be completely secure.
#11
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The Futaba system uses a channel for 3 miliseconds at a time before going to the next one. If you do get an unlikely hit from a cordless. It will be gone in a hurry.
David
David

Thanks everyone I feel more confident and I'm not paranoid.
Electrolight
#12

I think you have good reason to have doubts about the 2.4 systems! Check out this thread before go out and buy a 2.4 system. I am looking at new computer radios myself and have decided to go with a snthezied 72 mhz system. It can be converted to 2.4 down the road if I want by by plugging in a module into the Tx. [8D] http://www.rcuniverse.com/forum/m_6405339/tm.htm
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I don't know what scared you in there Fastsky. Basically all they said was make sure you have enough RX battery power and that even applies to 72 MHz systems. But it's your choice. I think you are more concerned, rightfully so, in the fact that you don't want to replace all of your 72 MHz receivers. That was the gist of your other thread anyway.
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I agree the batterie power is very short but I'm not concerned with that. The 6C FASST 2.4Ghz Rocks. I tested it next to my wifi router, my phone, and my wireless direct feeding camera and had no problem! I was constantly messing with the other things and no problem/interference nothing. At least not noticeably!
Now I have no worries!!
Electrolight
Now I have no worries!!
Electrolight
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ORIGINAL: Electrolight
I agree the batterie power is very short but I'm not concerned with that. The 6C FASST 2.4Ghz Rocks. I tested it next to my wifi router, my phone, and my wireless direct feeding camera and had no problem! I was constantly messing with the other things and no problem/interference nothing. At least not noticeably!
Now I have no worries!!
Electrolight
I agree the batterie power is very short but I'm not concerned with that. The 6C FASST 2.4Ghz Rocks. I tested it next to my wifi router, my phone, and my wireless direct feeding camera and had no problem! I was constantly messing with the other things and no problem/interference nothing. At least not noticeably!
Now I have no worries!!
Electrolight
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To understand 2.4GHz systems firstly you need to stop thinking in the same terms as you used to think when working with 35/36/72MHz systems.
Even if someone switches on, on the same channel as you are on (with a device such as a cordless phone or bluetooth transmitter), you will not be shot down. This is were the real advantage of 2.4GHz over 72/35/36MHz systems. This is done via binding the receiver to a transmitter with a unique code as implemented by all the major players (XPS, Spektrum(JR) and Futaba(FASST)). The receiver will look at all the data transmitted on its frequency and filter out the data that has its unique identity code. This may lead to a case of the system acting sluggishly due to some of the transmitter data getting lost in the noise. It is in the same manner that multiple laptops can operate using the same WIFI access point at the same time on the same frequency. The only true cases of interference that I have truly heard of is when the receivers are saturated due to the placing of a high powered transmitter right next to it such as wireless cameras. (You can simulate this also in the 35/36/72MHz systems by turning your transmitter on and placing it next to a receiver operating on a different frequency and you will see what I mean)
The main disadvantage of the 2.4GHz systems over the older systems is the problems due to the higher sensitivity of the systems to low power brown outs forcing the systems to "Reboot", but proper battery management and common sense seems to be the solution to this.
Cheers
Pupmeister
Even if someone switches on, on the same channel as you are on (with a device such as a cordless phone or bluetooth transmitter), you will not be shot down. This is were the real advantage of 2.4GHz over 72/35/36MHz systems. This is done via binding the receiver to a transmitter with a unique code as implemented by all the major players (XPS, Spektrum(JR) and Futaba(FASST)). The receiver will look at all the data transmitted on its frequency and filter out the data that has its unique identity code. This may lead to a case of the system acting sluggishly due to some of the transmitter data getting lost in the noise. It is in the same manner that multiple laptops can operate using the same WIFI access point at the same time on the same frequency. The only true cases of interference that I have truly heard of is when the receivers are saturated due to the placing of a high powered transmitter right next to it such as wireless cameras. (You can simulate this also in the 35/36/72MHz systems by turning your transmitter on and placing it next to a receiver operating on a different frequency and you will see what I mean)
The main disadvantage of the 2.4GHz systems over the older systems is the problems due to the higher sensitivity of the systems to low power brown outs forcing the systems to "Reboot", but proper battery management and common sense seems to be the solution to this.
Cheers
Pupmeister
#18

Battery voltage is one thing to consider about the 2.4 Spektrum systems....I'm not sure if this applies to the Fasst systems tho. It may but I don't know for sure. I have seen a few birds go down in flight with 2.4 systems due to low voltage to the RX while if it were a Standard 72mhz system it most likely would have made the rest of the flight and land safely. The 2.4 systems goes into a reboot mode at low voltage (or something like it) and I personally feel that 2.4 rx's should be ran on 6V's to lesson the possability of voltage reboot. At least you will be further away from the min voltage to start....
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ORIGINAL: Bruce88123
No such thing as a 6C. I'm sure you meant Futaba 6EX 6-Channel 2.4GHz. Just to clarify. 6EX now delivering, 7C and 9C coming soon and of course higher channel count sets in the future.
No such thing as a 6C. I'm sure you meant Futaba 6EX 6-Channel 2.4GHz. Just to clarify. 6EX now delivering, 7C and 9C coming soon and of course higher channel count sets in the future.

#20
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ORIGINAL: Electrolight
Thank you for correcting me. But you seemed to know what I meant.
ORIGINAL: Bruce88123
No such thing as a 6C. I'm sure you meant Futaba 6EX 6-Channel 2.4GHz. Just to clarify. 6EX now delivering, 7C and 9C coming soon and of course higher channel count sets in the future.
No such thing as a 6C. I'm sure you meant Futaba 6EX 6-Channel 2.4GHz. Just to clarify. 6EX now delivering, 7C and 9C coming soon and of course higher channel count sets in the future.

Plus, I think Bruce likes doing it anyway!!!







Ken