I know what my next heli is

[DierWolf]

same goes for putting 2.4Ghz camera's on your heli, its a nono, you have to use 900Mhz camera or you'll sure have problems.

[Ber60]

Erwin your heli looks very very nice I may well get one:)

Thanks, loved the work on it so much I am afraid to fly it but that will pass after the first crach I think. :)

[TPOG]

"Everyone with these new 2.4Ghz radio's feel they are pretty safe, thats because you dont see the real problem with 2.4.. Me as a Wi-Fi guru knows all about it.... you maybe fly with 5,6 7 i dont care its not much people flying at exactly the same time, get yourself a group of 20 guys and you all fire up your stuff and start flying about for a while and let me know."

At SEFF this year they had over 100 planes in the air to set the world record, and there were no reported probs with 2.4GHz...

[DierWolf]

LOL

Good job to them then.....

But let me be more specific.... There official record was 99 planes in the Air for 1 (ONE!!) minute!!.. (Read my quote i said fly around for a WHILE!)

please do elaberate on what happened to the other 41 planes that took off... ON top of that they were not all using 2.4Ghz and most were using FM radio's, this was not a record to prove the viability of 2.4Ghz if thats what you feel it was, i can almost certainly guarantee if all where 2.4Ghz not half would have left the ground.

Isnt it quite strange there is exactly 100 channels on 72 Mhz??? Also look at some vids, SEFF is known for Scale models, let me know if you saw anything in the air that was scale, rather all are 30 dollar training/light flyer toy kits most probably not run on 200+ dollar radios but cheap 30-60 dollar FM radio's... So if its a testiment to anything its more in the favor of FM.

please bring something better than that to the debate, and also Guiness didnt justify it as yet. I attended 2007, so i know a little about it as well.

[Ian 777]

Thanks, loved the work on it so much I am afraid to fly it but that will pass after the first crach I think. :)

I think you'll find things much easier with this heli mate:)

Do you know what the alloy is on the head and tail? I dont know how Mikes tail can have failed the way it did.:confused:

[DierWolf]

Stress crack or metal fault along that line in addition to the vibration and harmonics of the belt and tail rotor can certainly do it in.

[Ian 777]

Yeah Like I said I dont think it's down to soft metal the material is pretty hard. I think it's probably faulty stock but still to fail after 4 batteries without a crash! thats crazy:shock:

[DierWolf]

hey, calculate his tail speed LOL.... its no joke :)

I know my esmart was doing 10K rpm when it failed at the tail.

[Ian 777]

Same place?

[DierWolf]

Yep.. metal always fails at the weakest point.

which is why i said, maybe they try mill it a lil too thin in that section for (prettyness and weight loss)

[Jonnyheli]

DierWolf how do you know so much stuff?:confused:

-Jonny

[TPOG]

Well, if, as you say, most were using FM radios, perhaps you can explain what happened to the other 41 planes? Your logic is flawed on that point.

I didn't say it was an attempt to prove 2.4, that's your bias interpreting what I said. I was just pointing out that there were many 2.4s operating simultaneously without issue.

What's attending 2007 got to do with the record attempt this year?

And lastly, don't you dare tell me what to "bring" to a debate, it's called free speech pal. I'm not going to debate this further as you obviously have a bug up your ass about 2.4, and I'm always wary of self-declared "gurus". Lets just agree to disagree :tongue :)

LOL

Good job to them then.....

But let me be more specific.... There official record was 99 planes in the Air for 1 (ONE!!) minute!!.. (Read my quote i said fly around for a WHILE!)

please do elaberate on what happened to the other 41 planes that took off... ON top of that they were not all using 2.4Ghz and most were using FM radio's, this was not a record to prove the viability of 2.4Ghz if thats what you feel it was, i can almost certainly guarantee if all where 2.4Ghz not half would have left the ground.

Isnt it quite strange there is exactly 100 channels on 72 Mhz??? Also look at some vids, SEFF is known for Scale models, let me know if you saw anything in the air that was scale, rather all are 30 dollar training/light flyer toy kits most probably not run on 200+ dollar radios but cheap 30-60 dollar FM radio's... So if its a testiment to anything its more in the favor of FM.

please bring something better than that to the debate, and also Guiness didnt justify it as yet. I attended 2007, so i know a little about it as well.

[kgfly]

Hmmm, there is a great deal of misinformation circulating about 2.4GHz RC, and IMO most of this falls into that category.
I come from a long line of Wireless internet people and i know why 5.8 is much better and much more reliable than 2.4.What, your ancestors had wireless internet ? :dontknow

Its like asking me why i feel 2.4ghz cordless phones are better than 900Mhz Cordless phones. (They are not btw, 900mhz outperforms them, do a search on why, you may find yourself suprised your 2.4ghz radio's are doing the same thing)No it is not. Different applications.

But here's the short and nasty of it all... If you into anything Wi-Fi you should know this.Actually I do know a little about it. Did you know that the ISM band has no channels defined at all ? Each application makes its own use of the available spectrum according to the designer's choices. WiFi has a number of overlapping logical channels. Most video gear has a smaller number. Spektrum DSM defines 80 logical channels. Futaba FASST a smaller number. XPS has 12 IIRC. What's more, due to the nature of spread spectrum technology, all of these can coexist up to a point, that point being where the average noise floor exceeds the senstitivy and processing gain of the Rx.

The 5GHz bands have much greater spectrum available and there are 12 non-overlapping channels, each with 20MHz of bandwidth. This means significantly better performance as compared to the 2.4GHz band. I am not sure if allocation of 5GHz is globally uniform like the 2.4GHz ISM band? Is it really divided into 12 channels for all applications or is this just for one application you know about ? Logical channels of 20MHz are not better for the very low data-rate required by R/C than logical channels of 1MHz so your suggestion that this attribute alone means better performance does not appear relevant to R/C.

The entire 2.4GHz band is 80MHz wide, which only allows three non-overlapping channels.As described above, this doesn't make much sense for the ISM band. I guess you mean that if I want 20MHz channels with very wide guard bands I can only have 3. However that is irrelevant to R/C.

If high performance is an important requirement, then lean toward the 5GHz band.Perhaps you mean if high bandwidth is an important requirement ? Yet even that is not necessarily so.

Everyone with these new 2.4Ghz radio's feel they are pretty safe, thats because you dont see the real problem with 2.4.. Me as a Wi-Fi guru knows all about it.... you maybe fly with 5,6 7 i dont care its not much people flying at exactly the same time, get yourself a group of 20 guys and you all fire up your stuff and start flying about for a while and let me know. As mentioned, about 50 of the 97 planes in the air at SEFF were on 2.4GHz, 1 XPS, 2 FASST and the rest Spektrum. Given the risks involved in that 100-plane attempt, it is hardly suprising that all the planes were small and relatively low cost, that says nothing at all about the radio technology.

Like i said numerous times, this may not be the problem for you guys as you dont have tons of 2.4Ghz equipment around you, this is not the case on my tiny island. Which is why i prefer FM radio'sFair enough, it is your preference, but you have not provided any evidence of real world problems. I have flown in Silicon Valley, California. There would be few locations more saturated with WiFi coverage than that and yet Spektrum works without a hitch.

As for Vibration and Blindspot problems of 2.4 recievers its as easy as a search on Helifreak or Google. As for vibration its a simple look in the manual of a 2.4Ghz radio.

“The receiver contains precision electronic parts. It is the most delicate radio component on-board the model and should be protected from vibration, shock and temperature extremes.”This is universally true for all Rx. That is why people mount them in foam cushioning. I am not aware of any greater susceptability to vibration for 2.4GHz Rx over FM and nor would a 5.8GHz Rx be any less susceptible.

For instance 2.4Ghz cannot penetrate carbon Fiber and has problems also with Aluminum frames causing blind spots...Shadowing is indeed an issue, and will be worse for 5.8GHz due to its shorter wavelength. Are you stating that 5.8GHz can penetrate a CF fuselage that would otherwise block 2.4GHz ?

We can go on and on about this but i wount you asked why i feel 5.8 is better than 2.4 and i have already listed the reason why.Opinions without supporting evidence, Your reasons and you are entitled to them. I see a lot of "the sky is falling" posts without sound backing and when challenged, never get meaningful, substantiated references.

I am not trying to pick a fight with anyone, I just hate seeing the wider community being misled by unsubstantiated rumour or claims of impending doom when the reality is that 2.4GHz spread spectrum technology works extremely well for R/C both in theory and in practise, as demonstrated by the tens of thousands of users worldwide. Of course there are some failures, crashes and incidents. Most due to user error. Some due to the natural failure rate of all equipment. Some due to software bugs (that once discovered, have been fixed). Very, very few if any substantiated cases of failures due to the choice of the 2.4GHz ISM band or any inherent weakness in the technology.

In the US and possibly some other geographies there is an option to use 900MHz spread spectrum and some vendors are talking about offering R/C products in that band. The longer wavelength will mean longer antennae but also fewer issues with RF shadowing (unlike 5.8GHz which will make the problem worse). It will be interesting to see if 900MHz R/C emerges as a substantial player. The lack of global applicability may limit its appeal.

[DierWolf]

still missing my point i see....

here it is again... for you guys not surrounded with 2.4 equipment all around you its prefectly fine... for me and where i am at, it is not. its that simple.

Also the mere fact that people using 2.4 wireless Cameras for FPV with 2.4ghz radios as well all have problems and all switch to 900mhz cameras.

that in itself, one loansome piece of equipment proves its not as Secure of a channel as they will lend you to believe. It has its faults and many of them but you wount see it very often just in an open field with nothing around you but a few other flyers.

so again.. i wount use one because of the stuff around me, go ahead and use it if you want its no problem for you... Until something does interfere with it, most probably you'll never know what cuased it and chalk it up to "user error"

[kgfly]

still missing my point i see....

here it is again... for you guys not surrounded with 2.4 equipment all around you its prefectly fine... for me and where i am at, it is not. its that simple.No, didn't miss that point but thank you for clarifying it. Have you actually tested Spektrum or FASST at your location ?

Also the mere fact that people using 2.4 wireless Cameras for FPV with 2.4ghz radios as well all have problems and all switch to 900mhz cameras.

that in itself, one loansome piece of equipment proves its not as Secure of a channel as they will lend you to believe.All that proves is that if you put a high power transmitter within a few centimeters of the Rx it will raise the noise floor to the point that the Rx cannot extract the signal from the Tx. No suprise and not unique to 2.4GHz. If you put a 500mW 36MHz Tx on-board with an FM Rx you would have the same problem. The situation has not arisen as 36Mhz R/C band does not have room for and does not allow for video transmission, On the other hand, try flying close to a pager tower on FM and see what happens. Same problem.

Interference from narrow-band sources is far less of a problem for 2.4GHz R/C than it is for FM radios which is one of the significant advantages. However, no RF link is immune to interference or 100% secure and I agree that the hype about 2.4GHz R/C systems has been predictably over the top. However it is fair to say that the top-shelf implementations are vastly more secure than FM for many reasons including:

* No risk of shootdown
* Orders of magnitude better Rx sensitivity and tolerance of low SNR
* Highly tolerant of narrow-band noise, orders of magnitude more than FM
* More tolerant of wide-band noise than FM

It has its faults and many of them Another unsubstantiated generalisation. Care to identify the faults ?

[mnwizard]

I don't know enough about the subject to argue either side, but I just came accross this ad in the new RC Heli magazine and thought you guys might be interested -
http://i26.tinypic.com/2nsmgbn.jpg

[Ber60]

WOW, loving it, a great "clash of the titans" and I don't mean the heli's :YeaBaby:

[Ian 777]

Mmm would be good if we could have Wagners Ride of the Valkeries playng as an accompanyment:YeaBaby:

[another_finn]

GSKL5E3zSjs
http://forums.pcpitstop.com/style_emoticons/New_emoticons/popcorn.gif

[Ian 777]

Oh Far out man What a perfomance :clappp:clappp:clappp:rolling:rolling:rolling

Yes that definately evokes some wondeful mental imagery.

You know I think we could start selling tickets

Nice one Mika:hug:

[DierWolf]

roflmao, i knew finn would come up with something super funny.


So now tell me, why only with 40 radios??? its because just like in wireless internet 2.4ghz, beyond that point and in some cases even fewer than 40 radios you start to get interferrance... if they plugged some software into there to measure the RSSI and Noise to Signal Ratio they would see exactly whats going.... the Signal level stays very nice and high but 2.4Ghz and even 5.8Ghz its the Noise to Signal Ratio (or Quality) of that signal is what important and at a given number of radios operating at any time that RSSI drops Dramatically and you start to have lots of problems.

Radio manufacturers for radios like the DX6i advertise it as THE MOST SECURE and will NOT get any interference... this is what i am saying they WILL! get interference just not as likely becuase of how and where its being used.

which again brings me back to saying, where i am at its simply not very SMART to use one becuase of all the WiFi Stuff around you.

Yes 2.4 cameras used for FPV has higher wattage pumping out 500mw is not that much btw, We have 8 Watt boosted 5.8 Ghz antennas right next to eachother on the hills creating the backbone back over the hills to get coverage to the other side of the island and no problems... if you put a 500mw booster on 2 x 2.4Ghz even 3 feet from eachother they have huge problems... Again like i said 5.8 is better.

my experience with 2.4Ghz ended pretty nasty with interference and the loss of a 1400 dollar boat, think thats enough testing for me. That coupled with the problems we face with all 2.4Ghz stuff deployed is more than reason enough for me not to want to use 2.4Ghz on my birds.

We can debate all day long, but in the end it will all still be the same.... you wount see the problems i will see simply because your not operating it in an environment such as mine.

All i am saying to people is, dont believe the hype, its not as secure as they would make you believe and it is prone to interference.... As the USA Catches up on Wi-Fi internet people will start seeing problems..

Nice way to test is to drive around in the city with your wireless laptop, find a spot where you can see maybe 8 or 9 access points and stop right there and go hover your 2.4Ghz ready Heli and let me know how it goes.

this is the situation i am faced with, on top of all the access points on the hills we have here pretty much every home has a linksys router as well, which i know for a fact can even provide signal to the next door neighbour thru Concrete walls (busted a few poeple selling our internet that way) So where i am 2.4 is littered everywhere.

Even my 2.4 Ghz camera sitting a foot away from the base station pics up interference as was shown in one of my video's on youtube.

As for my Ancestors LOL, ja maybe i worded it wrongly but 2.4 Technology has been around for like 15 years, but Wi-Fi to some of you younger ones might only mean 2.4Ghz while back in the day when i started Wi-Fi to us was Packet Radios, yeah were talking back when the internet first started with only local nerds running small bulletine boards from their basement to their neighbourhood.

Quite done with the discussion really... you wount see the problems i will see so its useless to debate it.

[testpilot58d]

Ber,
Your copterX looks very sweet!

[kgfly]

So now tell me, why only with 40 radios??? Most likely because that is the nominal recommended limit and that is what they wanted to test. However we know from both theory and practice that it is not the actual limit. The Spektrum system divides the ISM band into 80 logical channels and uses two per operating Tx/Rx pair. Hence the nominal limit of 40 units. However, in reality the nature of spread spectrum and the fact that they use very low duty-cycle transmissions means that in an otherwise clean signal environment you could have many more, certainly double that and maybe well beyond.

its because just like in wireless internet 2.4ghz, beyond that point and in some cases even fewer than 40 radios you start to get interferrance... We certainly agree on this, the fundamental issue is the background noise floor seen by any one Rx due to all sources in the band visible at its current location.

if they plugged some software into there to measure the RSSI and Noise to Signal Ratio they would see exactly whats going.... the Signal level stays very nice and high but 2.4Ghz and even 5.8Ghz its the Noise to Signal Ratio (or Quality) of that signal is what important and at a given number of radios operating at any time that RSSI drops Dramatically and you start to have lots of problems.Quite so. Of course on FM it only takes one other source on your frequency to cause complete disaster. With spread spectrum you get a progressive degradation (seen as sluggish response in an RC application).

Radio manufacturers for radios like the DX6i advertise it as THE MOST SECURE and will NOT get any interference... this is what i am saying they WILL! get interference just not as likely becuase of how and where its being used.I agree. It is certainly the most secure R/C solution so far but is not immune to interference.

which again brings me back to saying, where i am at its simply not very SMART to use one becuase of all the WiFi Stuff around you.Perhaps around you, we don't know as there is no evidence of an air system being tested. Around most people it is no problem. I operate mine right next to a WiFi laptop, 2.4GHz cordless phone and less than 10m from a WiFi base station all without any problems and my neighbours on all sides have WiFi too, up to four networks visible at a time. And as I said, Spektrum flies just fine in many locations in Silicon Valley and while it is possible your WiFi coverage is more intense in your location that it is there, I would be suprised.

Yes 2.4 cameras used for FPV has higher wattage pumping out 500mw is not that much btw, It is both the power and the proximity. Of course there are some that are only 10mW and some that are 2W or maybe more.

We have 8 Watt boosted 5.8 Ghz antennas right next to eachother on the hills creating the backbone back over the hills to get coverage to the other side of the island and no problems... if you put a 500mw booster on 2 x 2.4Ghz even 3 feet from eachother they have huge problems... Again like i said 5.8 is betterThis is misleading, you mean it is better for that application since the designers use different approaches, overlapping channels for WiFi and from your description, isolated channels for your 5.8GHz backbone. That doesn't make it better for all applications unless they all work the same way.

my experience with 2.4Ghz ended pretty nasty with interference and the loss of a 1400 dollar boat, think thats enough testing for me. That coupled with the problems we face with all 2.4Ghz stuff deployed is more than reason enough for me not to want to use 2.4Ghz on my birds.I am sorry to hear about your loss. I understand better your concern. Surface use of 2.4GHz, particularly over water is a different situation. 5.8GHz might indeed be better suited for marine R/C as it may be less susceptable to absorption by water. Of course 2.4GHz R/C for cars/trucks has been used with great success for 3 or 4 years now. Initial problems were quickly resolved and not I believe that all serious competitors use it and that is frequently with 30 or more on the track at a time.

Even my 2.4 Ghz camera sitting a foot away from the base station pics up interference as was shown in one of my video's on youtube.Quite so. The noise is registered, the issue is whether it is a problem for reliable R/C reception. Generally it is not, it has to become extreme.

You think extreme levels of background noise will become common and hence 2.4GHZ R/C will become unreliable or even dangerous, as do some others, time will tell.

[Ber60]

Ber,
Your copterX looks very sweet!

Thanks, been setting it up for about 3 days now, I want it perfect for her maiden flight (or crash :)) , my esc burned out so I bought the scorpion motor and esc for this bird, now thats a engine ! :glasses2:

[helihathnofury]

I am tempted by this little beauty next time I go to the USA

http://www.xheli.com/version-2-exi-450-helicopter.html

Like the copterx too, Erwin.
:thumbup:
Mike