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        Question 2.4 giga is being jammed. AMA needs to get us a frequency again.

#1 cyclops2 Oct 27, 2012 01:55 PM

2.4 giga is being jammed. AMA needs to get us a frequency again.
 
We need dedicated frequencies for RC again.
Also the manufacturers are picking the transmitters frequencies. ....If they give more than 1 transmitter the same frequency, NO one really knows. Everyone is so positive they are the only one on that frequency......Prove it...........We are running on blind faith.........

Kind of like believing a bank would never give out bad loans.

#2 JetPlaneFlyer Oct 27, 2012 02:07 PM

You might want to do some research on how 2.4GHz works before jumping to conclusions.
2.4GHz is a band which covers a wide range of frequencies. Most 2.4Ghz systems 'hop' between multiple different frequencies many times every second. The chance of two Tx's hitting the same frequency at the same time is very low but even if they do it doesn't matter at all because a nano second later they will have 'hopped' to another frequency. The Rx is 'bound' to its Tx so it ignores any other signals anyway.

2.4Ghz is as near to bullet proof as it's reasonably possible to get.

Read this: http://www.3drcforums.com/content.ph...dio-Technology

#3 AndyKunz Oct 27, 2012 02:32 PM

Quote:

Originally Posted by cyclops2 (Post 23114982)
We need dedicated frequencies for RC again.

What's wrong with the ones we already (still) have? You can go back to 72MHz if you want.

Everything JetPilot said is true.

Andy

#4 Lou Oct 27, 2012 02:38 PM

:eek: Lose a plane today?

If 2.4 is being jammed, it may not be by your buddy at the field but by a large number of other devices that where ALREADY on 2.4 before the transmitter manufactures began using it.

As well, there are places that the receiver is just swamped by other noise.

#5 Rockin Robbins Oct 27, 2012 04:01 PM

Please keep in mind that 2.4 GHz is strictly line of sight. It can be blocked by just about anything and reflections can give you multipath interference. Plenty can happen to your signal and as others have already said, jamming is completely improbable.

#6 Mr. foambuilder Oct 27, 2012 04:05 PM

2.4 has been proven time and again to be a safe and reliable frequency. As stated above, you are not there on one freq. long enough to be affected. If that were the case, you would not even be able to do a setup on your radio at home with the 2.4 bouncing off the walls of your home. 2.4 IS NOT the problem, rather poor installations and or poor flying skills. Just my $0.01 worth, due to the devaluation of the dollar:D:popcorn:

#7 JetPlaneFlyer Oct 27, 2012 04:24 PM

Quote:

Originally Posted by Rockin Robbins (Post 23115795)
Please keep in mind that 2.4 GHz is strictly line of sight. It can be blocked by just about anything and reflections can give you multipath interference.

Well actually not quite as bad as line of sight. Unlike sight 2.4GHz will pass though glass fibre, wood, film covering and/or foam without any real problem. If you consider your home 2.4GHz wireless connection that will actually pass through walls and closed doors etc albeit with reduced range.

It's metal and carbon fibre that block it outright so your batteries and motor and such like will cause shadows, hence the multiple aerials so they don't all get shadowed at once.

#8 RC Man Oct 27, 2012 06:48 PM

900 MHz, 5.8g and other frequencies are legal for RC it’s just that no one makes RC radios on those frequencies.


The robustness of 2.4 is very dependent on the manufacture of your radio. Spektrum has the worst reputation for having RF link problem is high traffic areas. After I switch to Futaba FASST I have never had any more problems.


.

#9 C₄H₁₀ Oct 27, 2012 07:19 PM

Switch to mind control. You'll have no more issues unless someone tampers with your morning coffee.

#10 Lou Oct 27, 2012 07:49 PM

@cyclops2

The 2.4 band is also know as the ISM band; for Industrial, Scientific and Medical. There are a ton of devices on this band. Wireless routers, cell phones, alarm systems, garage door openers, the cordless phone in your house (though some are now in the 5 band).

Several years back Cisco, Nortel and other companies had a big pow-wow to discuss the possible interference of 'other' non ISM devices. They pretty much won, big business being what it is. In short, we are the new kids on the block and we are using a bandwidth that has long been used by other, bigger, national and international concerns. They probably have the clout to toss us out, but did not.

Going to a dedicated, single channel for each receiver is near suicide. The SS/FHS is far more secure and offers far more protection against the ISM devices already in use. Wi-Fi outfits are already moving to the 5 gig band due to congestion in the 2.4 band.

The RC manufacturers did the right thing by using SS/FHS.

#11 cryhavoc38 Oct 27, 2012 08:01 PM

Quote:

Originally Posted by Mr. foambuilder (Post 23115814)
2.4 has been proven time and again to be a safe and reliable frequency. As stated above, you are not there on one freq. long enough to be affected. If that were the case, you would not even be able to do a setup on your radio at home with the 2.4 bouncing off the walls of your home. 2.4 IS NOT the problem, rather poor installations and or poor flying skills. Just my $0.01 worth, due to the devaluation of the dollar:D:popcorn:


Not exactly true of some of the older systems like DSM2
DSM and DSM2 do not hop. They grab onto two frequencies and stay there.
There is no hopping with DSM2 which a great many users are still flying/using

#12 cyclops2 Oct 27, 2012 08:54 PM

I posted this topic after I read about a RC meet where all Gigas were being jammed & could not fly.

Modelers asked if the police / anyone else, would shut down long enough to verify the higher powered vehicles were the jammers.
Officials said they could & would not shut down for a interference.check.

It was on RC Groups or Universe.

#13 Gohmer Oct 27, 2012 10:02 PM

All modelers should have hopped at the same time. That will break up the jam

#14 C₄H₁₀ Oct 27, 2012 10:13 PM

How often should I grease my transmitter's RF module to prevent jamming?

#15 zeezee Oct 27, 2012 10:31 PM

1 Attachment(s)
C4H10, what if we learn to control our planes with our minds and an Observer shows up on the "Fringe" of the field and reads you? Have you learned to block your thoughts yet? Hurry, it takes a year.....For this I modified a Pitts with a detachable anti-jamming drone atop it to correct this injustice. Dave/zeezee :cool:


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