^Horatio>

Does anyone here actually know the output power of these new 2.4gHz systems? Compared to the 'old-school' 'normal' FM/PCM systems?

Just interested to see if the limits imposed on our usual radios apply to the new technology, or whether in fact the new systems have more/less transmitting power than before. I know for surface models, the Spektrum stuff has been pretty good once the bugs were ironed out. But for Aero stuff, I'd like to know if there were going to be any range issues etc.

It makes perfect sense this 2.4 stuff, I know the military have been using similar systems for a long time - but without any restrictions imposed.

onewasp

Yes, you are right we have had this conversation before-------However you didn't indicate whether or not you had checked this out with the HAMs at your Radio Mfgr's US location

As I mentioned when we last discussed this I have and they did more than just 'CONFIRM' my findings.

Check with nicetie down Texas way--------seems he has my experience not yours.

However, as I said both before ---- and on this thread when you are nailed by 1500 watts ----you will know it.
Since we last 'discussed the issue' the last six meter flier in our area has put his gear up for sale and is awaiting his new 2.4GHz rig.

Since my only purpose has been to alert other HAMs I hardly have an ax to grind or, quite frankly, any interest in six meters for RC., financial or otherwise.

Did you also check ARRL's propagation charts on six? Revealing to say the least.
How would you expect clear skies with those numbers?

swk550

My Feedback: (76)

I can not tell from the pictures. Will the new JR12X Tx have tripple rate Aileron, Elevator and Rudder? I use these features on my 10X.

Steve

Bob Pastorello

My Feedback: (198)

steve, if you download the larger image of the 12, it's pretty clear..... the switches have "0", "1", "2", just like the 10X.... apparently, it will have triple rates.

swk550

My Feedback: (76)

Bob,

Thanks. I may wait for the 12X.

Bob Pastorello

My Feedback: (198)

V2PLUS10

I called and backordered a X9303 2.4 system today. At the time I asked if my old 9303 could be sent in and retrofitted with the new 2.4 rf section etc. I was told that the internal parts were all different, all IC stuff, and that the case also would be different. Perhaps the pictures they show on the web site are just touched up photos of the old style transmitters. I cannot imagine the new 2.4 systems having fewer features that the old 9303 and 10X systems that they replace...

Randy

Bob Pastorello

My Feedback: (198)

There are 'half moon' slide switches, look to be momentary, on the upper outboard corners of the gimbal facings. Talked with someone that was there today at Toledo - confirmed it is so. Don't know what they're for....

The x9303 is probably the 9303 mechanically and cosmetically, with completely new innards. But probably identical software. This is all sounding pretty good to me.

Notice the 9 channel RX antenna.... one is at 90* on the main RX. Interesting. Must have been something learned from the AR 7000... at any rate, $169 street price for the RX, with one remote RX is sounding pretty reasonable, I suppose. Weren't the 9 ch PCM Dual Conversions around that, or more?

Oh - my source also says "late June - mid July" possible for the 9303, but no guarantees.

V2PLUS10

I have a couple of JR R945S ten channel dual conversion (the only "dual conversion" offered by JR) and they were about $210 each. I wanted the best of the best( my opinion!) for my scale airplane so I went for the JR top of the line....now it may end up in the box with the old Controlaire Mule receiver!!! The Hanriot, now has an AR 7000 rx...tested but not yet flown.....

Randy

visioneer_one

My Feedback: (506)

Ahem.

callen

A guy crshed a full scale airplane yesterday at SRQ. He immediatley stated after clearing the wreckage he was sure he had a lock out on his DX 7 system. The only trouble I ever have is when I turn it on with the tx right on top of the rx. Then I have to cycle it on and off.

KC36330

they replace the hover pitch and hover throttle trim pots (now digital trim to the pitch/throttle curves) which are now Aux 4 and Aux 5, the pots that were Aux 4 and Aux 5 are now chan 11 & 12.

kc

aviti

My Feedback: (54)

Huh? He was flying a full scale plane with a DX7? Was it a Cessna 172?

JBanks523

My Feedback: (17)

Definetly some good info here! Can't wait for these new systems to come out! When I read about these yesterday morning on a couple of other sites I was instantly revved up and ready to yank all my 72mhz receivers in preparation for 2.4!!!! Glad to see the release info made it over here as well!

NikolayTT

One should check with the local authorities. For 2.4 GHz in Europe is either 250 mW and might be even down to 50 mW which makes Spektrum
well out of the law. I asked them but no answer came. In UK that is higher and in USA could be even higher up to 1500 mW. Still based on
practical experiments and also what is used in life-saving systems, as in millitary, the power in those frequencies is up to 10 Watts, and
boosting it up might cause coverage distruction; that is due to multiple reflections, which cause subsequent field phase modulations in a
random manner. Simply, if you want to see it, then just drop two stones at ones with one hand in calm wather and the pattern of the
surface is going to be quite similar to what I am mentioning. And as you guess it already - in the Air - those NASTY(!) things are
even 3-dimensional and Invisible, that is why more receivers and antenas are better. The biggest problem is that no one of the
current manufacturers adressed (or wanted to address) this classic problem described since couple centuries ago by the early works
of Maxwel, Faraday etc. and instead ot that they tell us how to programm the features and mixers, which is too simple compared to
that nasty radio-wave propagation. Sure there are many success stories in 2.4GHz but we need to know about the artifacts more
anyway. The future is the for sure the Digital Communication approaches 2.4GHz but let see when that technology will get out of
its baby-stage of ANTENA development for RC. Of course some people prefer to be excited than to look into the problems, but
everybody is free to spend his money as he wants, isn't it. If you want to know more about, check so called MIMO-Antenas for the
Mobile Wireless Communications, WLANS and WCDMA phones; there the developments are about maybe 5 years ahead of that
we see at Spektrum, no jokes, this is very serious multi-billon-dollar business indeed.
Cheers,
Nick

^Horatio>

Nick

Many thanks for your informative post. 2.4 seems like the perfect solution to all our flying needs and wants, convenience, improved performance, telemetry - interesting possibilities with on board sensors.

However, the transmitting power is obviously relevant to us all, regardless of what we fly. It strikes me as a pretty fundamental aspect that could easily get overlooked whilst we're all busy drooling over the the response, resolution, mixing and other high-tech features of this new digital radio gear. If there's one thing I've learnt during my RC experiences - it's never to assume anything.

The typical FM/PCM radio gear has a transmitting power of 500mW. With the new stuff, I don't really like the thought of flying totally ignorant of some of the most basic and crucial information. Looking at Spektrum's site, on the FAQ page, range is conveniently brushed aside - because there are 'too many variables' - yet it would have been very easy to quantify the precise output power. So what is it?

We all need to know, to ensure that our models don't fly out of range, that we remain legal in the country we operate and thus properly covered by our insurance. Until the spec of these new radios is revealed, perhaps people need to be a tad less hasty! The thought of somebody flying a scale Jet at high speed into a random place on the ground is pretty frightening, lulled into a false sense of security that their radio link was unbreakable. [:@]

HankScorpio

Just saw this thread, this is fantastic news. We now have three (kind of - depends how you think of Spectrum/JR) radio manufacturers producing frequency-hopping-spread-spectrum radios (I don't believe anyone makes CDMA RC systems). This means:

1). Competitive flyers will have few hassles competing overseas, with module/receiver frequencies. Everyone will be at 2.4GHz. (kind of, hopping about the place anyway in a pseudo-random sequence).
2). This will put a burner up the posterior of the local rip-off merchants ... err ... I mean distributors - and end their monopoly, as we'll be able to buy a 2.4GHz radio anywhere on the planet and use it anywhere. If prices do not converge, then there is an arbitrage.
3). I'm sure the technology will have teething problems at the start, but once sorted out having a plane shot down by a careless idiot will be a thing of the past.

Great news, thanks for the link and info. I also heard rumors about a JR 16X a while back, but I am not sure if that is pure fiction.
[8D]

DesertHucker

You can not compare the transmision power between 72mhz and 2.4ghz someone with more knowledge than me may be able to explain it better. But as i believe it to be the higher the frequenzy the lower the transmision power to get the same range.

Max1965

I love my DX-7 and have ordered the Spektrum module for my JR 9301.

One word of warning concerning the DX-7. I had a problem in range checking with one of my Spektrums(I have two). The problem(which I tracked down myself)was the antenna coaxial cable. The coaxial cable "snaps" onto a curcuit board using a sort of minature 9 volt battery type of connector. The snap connector was not connected very well and a few of the little fingers were bent. I corrected the bent fingers....re-attached the coaxial cable and applied a spot of glue to hold it in place.........problem solved. Just saying.....you might want to check your system out....course you would have to decide on a crashed plane(and a dangerous situation)or the radio warrenty. In my opinion the 2.4 system is great but Spektrum(and maybe JR)need to come up with a different way to attach the antenna coaxial cable.

V2PLUS10

Was that the AR7000 reciever?? I haven't looked yet but can the case be easily removed and replaced?? I think this is worth checking out.

Randy

SitNFly

My Feedback: (54)

I was wondering how robust that cable might be over time. I have a 9303 that would be a candidate for the module but the antenna cable looks a little flimsy. It does appear the module made by Futaba has an internal antenna connection. No external cable. We shall see; this is fun.

ELECTRONS

FUTABA WAS BAD MOUTHING SPEKRUM SAYING THEIR CHIPS WERE NOT STATE OF THE ART. ONE OF OUR CLUB MEMBERS BOUGHT THE CHEAPER FUTABA AND AFTER ONLY TWO WEEKS CRASHED HIS PLANE BECAUSE HE SELECTED THE WRONG MODEL MEMORY. MODEL MATCH IS THE GREATEST. MANY PEOPLE MAY HAVE A NEED FOR A 12 CH 30 MODEL $700 RADIO. I HAVE TROUBLE WORKING FOUR CHANNELS. I LOVE MY SPEKRUM. I FEEL BAD ABOUT SELLING MY POLK AND FUTABA 72 MHZ RADIOS. I SHOULD HAVE RECOMMENDED SPEKRUMS TO THOSE NEW GUYS ENTERING THE HOBBY. 2.4 HAS AN EXTRA ADVANGE. YOU CAN NOW HAVE TWO FLYING SITES CLOSE TOGETHER. WITH 40 SLOTS NOT LIKELY YOU WOULD HAVE TO WAIT FOR AIR TIME. I HAVE ALWAYS WANTED TO FLY MY ELECTRICS AT THIS REALLY NEAT PARK NEAR MY HOUSE WITH A ASTRO TURF RUNWAY; BUT IT WAS TOO CLOSE TO A CLUB FIELD TO DO SO. NOW I FLY IN TOTAL SAFETY FOR ME AND THEM. ONE PRECAUTION. IF THE TWO AREAS ARE CLOSE ENOUGH FOR EACH TO SEE THE OTHERS PLANES LET THEM KNOW WHAT YOU ARE DOING SO THEY DO NOT BECOME WORRIED.

Harleyflyer

My Feedback: (9)

I currently have a 9303 and plan on staying with JR for now. Just curious though, does anyone have any information or thoughts on the Spektrum/JR 2.4 technology versus the Futaba 2.4 technology? I didn't realize until just yesterday that Futaba uses only one receiver, does some sort of channel surfing, etc. I am just curious about the pros and cons of each technology. Maybe we will have to wait and see as it is so new....at least from the Futaba side.

ELECTRONS

TYPICAL 72 MHZ OUTPUT POWER IS 200 TO 250 MW. OVERALL TX POWER COMSUMPTION IS .5 W THE ANTENNA SYSTEM (QUARTER WAVE END FEED ON RX AND 5/8 BODY GROUND PLANE ON TX) IS VERY INEFFICIENT. 2.4 ANTENNA SYSTEMS ARE A LITTLE MORE EFFECTIVE. IT IS VERY DIFFICULT TO ACTUALLY MEASURE OUTPUT FROM A DEVICE THAT IS SPREADING ITS ENERGY OVER A WIDE BAND OF SPECTRUM. RANGE IS A FUNCTION OF RX SENSITIVITY AND POWER OUT AND BANDWIDTH. MY FUTABAS AND POLK TRACKER 2 AND 3 BOTH TESTED CONTROL TO 1180 TO 1200 METERS. WE STOPPED TESTING THE SPEKRUM AT 2000 METERS OUR WALKIE TALKIES STARTED TO BREAK UP AND WE WERE NOT ABLE TO CONFIRM OPERATION AT 2100 METERS. THESE WERE APPLES TO APPLES TESTS AT SIX FEET ABOVE GROUND. ACTUAL AIR RANGE WOULD PROBALY BE MORE. I HAVE FOUND THAT RANGE IS REDUCED WITH THE ENGINE RUNNING IN SOME MODELS. I HAVE NOT FOUND THIS WITH 2.4. ALSO LONG SERVO LEADS AND WIRE PULL/PULL HAS REDUCED RANGE IN SOME MODELS AGAIN NOT SO WITH 2.4. NOISE REDUCTION SERVO LEADS ARE NOT NEEDED WITH 2.4. 2.4 ENERGY IS STOPPED BY LEAVES; SO DO NOT FLY BEHIND TREES!! DO NOT SHIELD ANTENNA (RX) WITH ANYTHING RF PROOF. METALS AND SOME COVERING LIKE MONOKOTE SILVER/ALUM OR ANY PAINT CONTAINNING METALS. AS ALWAYS RANGE TEST BEFORE FIRST FLIGHT OF THE DAY. AND BATTERY TEST BEFORE EACH FLIGHT. TAKEOFFS ARE OPTIONAL LANDINGS ARE NOT.

ELECTRONS

FUTABA HAS TWO RX JUST IN ONE PACKAGE. TWO ANTENNAS EXTEND FROM RX PACKAGE VIA COAX CABLE FOR ANTENNA DIVERSITY POSTIONING.