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Jeremy - I would not alter the composite structure to accommodate the <br>2.4 setup. When I setup my plane for 2.4 I put one remote inside the <br>(painted) canopy as high as possible and another in the bottom of the <br>fuse well behind the wing. My thinking is that most of the time we are <br>up flying, we are actually looking up at the bottom of the fuse which <br>would put that remote in clear view. The one in the canopy would also <br>get a clear view most of the time and either top or bottom would be in <br>view during rolling maneuvers. The main receiver goes where it fits and <br>may have a clear view too. My Zeque has lots of things to block the <br>view of the 2.4 since it has a carbon cowl in front, a full length <br>carbon belly pan and the big 10S 5000 battery pack. I don't have the <br>data logger installed but it range checked on the ground past 80 paces <br>in all directions and has been flawless in flight so far.<br><br>Chris<br><br>JEREMY CHINN wrote:<br>> OK.... 2.4 question for everyone.<br>><br>> I'm about 70% done with my first 2m pattern plane. All scratch built. <br>> It is an electric and will have 2.4 for guidance (Dx7 AR7000).<br>><br>> The fuselage has carbon fiber veil laminated to the insides of the <br>> outer skin, and there is a 1/4" dia thin wall carbon tube on either <br>> side of the fuse, both below the wing and above the wing.<br>><br>> My intention with this airplane is to mount the main reciever in the <br>> fuse behind the wingtube, and approximately 2" behind the 2 5S <br>> batterys in the fuse. I then intend to run the remote reciever out the <br>> bottom of the fuse and rearward approximately 4-5" from the main <br>> reciever. The satellite will be well behind the carbon fiber veil <br>> laminated area and should not be blocked by it in any way.<br>><br>> My hope is that the satellite will be far enough away from the batts <br>> and all the carbon reinforcement to get a clear signal at all times. <br>> The main rcvr has the possiblity of being blocked by the veil in the <br>> fuse, the carbon tubes and wing tubes in the fuse and the batts. I am <br>> of course trying to get it as far away from these things as possible <br>> to prevent any blockage.<br>><br>> Any thoughts on this? Should I remove the veil from the area where the <br>> main rcvr will sit so I can get a clear signal to it as well?<br>><br>><br>> ------------------------------------------------------------------------<br>> From: ed_alt@hotmail.com<br>> To: nsrca-discussion@lists.nsrca.org<br>> Date: Fri, 27 Jun 2008 09:13:45 -0400<br>> Subject: Re: [NSRCA-discussion] 2.4Ghz<br>><br>> Great tips here from Troy.<br>><br>> For reference, I almost never have a frame loss and I check after<br>> almost every flight. I am getting roughly 40 to 80 fades in the<br>> main receiver, usually tens to twenties on the remotes after a 13<br>> minute flight. The main receiver is often a higher number of fades<br>> because it just naturally has more junk near it which either<br>> reflects or absorbs RF energy. Wire bundles and closer proximity<br>> to the fuel tank and CF wing tube are what make the fades higher<br>> for the main receiver in my setup.<br>><br>> I have noticed a definite correlation of higher fades with being<br>> "blocked" by the fuel tank. At one time, I had a remote on the<br>> fuselage side, adjacent to the tank. That remote would give me<br>> about 120 fades per flight until I moved it away from the tank.<br>> Think about how a microwave oven works. A cup of coffee heats up<br>> from the molecules being excited by the RF radiation. The same<br>> exact principle is in effect with the minuscule power level of the<br>> signal reaching your model, so the fuel in the tank turns that RF<br>> energy into a miniscule amount of heat, while reducing the signal<br>> level that makes it through the other side. It's a highly<br>> localized effect; just getting an inch or so away (ahead of behind<br>> the tank location) improves the performance noticeably. This is<br>> just the physics of the beast, so it makes no difference what<br>> brand of 2.4 you fly, you want antenna placement to be in the<br>> clear as much as possible. Ignore the marketing, pay attention to<br>> making unobstructed paths for your receivers! The data monitor is<br>> a great tool to assure you have a good setup before you ever fly,<br>> then monitor performance for degradation from a known good<br>> starting point.<br>><br>> Ed<br>><br>> ------------------------------------------------------------------------<br>> Date: Thu, 26 Jun 2008 13:26:59 -0700<br>> From: troy@troynewman.net<br>> To: nsrca-discussion@lists.nsrca.org<br>> Subject: Re: [NSRCA-discussion] 2.4Ghz<br>><br>> Allan,<br>> in a range test situation you are going to be getting the<br>> worst possible readings on the flight data log. You could be<br>> holding the range test button and be on the fringes of loosing<br>> range yet the system is still working. The Flight data device<br>> will tell you exactly that. Which it did.<br>> Here is what I do with the data log device. I will use a<br>> second person to hold the model. I then will walk to a spot<br>> where the data starts to show lager numbers of fades. Its<br>> doing its job telling you the signal is getting weak.<br>> I then will find the spot a little closer that has the best<br>> "low" fades. This is where the signal starts to get "fuzzy"<br>> and the range is still solid but further out it starts to<br>> increase the fades. With the model on the ground, and you on<br>> the ground "level with it" the range test button depressed you<br>> are giving the system its worst possible scenario. Of course<br>> the flt log will show this.<br>> I then will make a note of this location where the range<br>> starts to fade.<br>> Simply walking until it stops working like we did with 72mhz<br>> stuff is going to show a ton of fades....Remember this thing<br>> is taking readings 50-60 a sec. So to get 200-300-500 fades<br>> putting the range test process in place you are are only<br>> talking about 10 secs. tops with weak signal. So think about<br>> what is going on...this is a tool and along with it comes some<br>> analysis of what is really happening and what the numbers<br>> mean. Its not a device that is a green light for go and red<br>> light for NO.<br>> So find the spot where you are not getting large numbers of<br>> fades..this is your range check distance.<br>> Now start up the engine and go to this same spot....you could<br>> have similar numbers of fades...remember that a given antenna<br>> may be blocked partially depending on model orientation to you<br>> and the TX. So I will walk around the model at this given<br>> distance and have my buddy looking at the flt data log.<br>> This tells me how its performing. Is this type of device for<br>> everybody Nope its not but its a powerful tool if you think<br>> about what the tool is telling you. The real test is in the<br>> air, because the data logger is going to rack up bigger<br>> numbers while under the range test scenario....but fly it and<br>> you will see what is happening. Also in looking at those<br>> number 100fades is about 2-3 secs worth of weak signal....this<br>> is a really small amount of time, and it doesn't mean the<br>> system is in hold...it just means a given antenna is getting<br>> weak signal for that amount of time. Compared to the number of<br>> seconds in a flight...that's low, and beside a fade doesn't<br>> mean its not getting signal just that its weak signal...and<br>> the signal from other antennas are stronger and the system is<br>> using those.<br>> If you have a weak signal for all antennas at the same time<br>> you could get a frame loss. It takes 45 frame losses in a row<br>> to make the system go into hold and this all happens in less<br>> than a second. So to really look at these numbers they have to<br>> be really really high to have a problem..<br>> For normal use in a pattern model I'm getting about 100-150<br>> fades on the main A-B antennas and low numbers on the remotes.<br>> My remotes are behind the wing down the tail of a wood model.<br>> I have the remotes with antennas mounted in different axis and<br>> planes to get the best diversity possible. I often have single<br>> digit fades on the two remotes. Its common to get a few Frame<br>> losses but its also common to have zero. I have seen numbers<br>> as high as 20-30 on the frame losses...never seen any holds<br>> from a flying situation.<br>> Turning your RX on before the TX can affect your numbers and<br>> of course turning the TX off before the taking readings on the<br>> RX will also add to your numbers.<br>> Obviously the instructions for this little device are not as<br>> clear as they could be but if you think about it and what the<br>> data is telling you...its well worth having it. Just think<br>> about the numbers mean and how quickly the tick marks can<br>> build up in a range test situation.<br>> Troy Newman<br>> Team JR<br>><br>> ------------------------------------------------------------------------<br>> *From:* nsrca-discussion-bounces@lists.nsrca.org<br>> [mailto:nsrca-discussion-bounces@lists.nsrca.org] *On Behalf<br>> Of *AWorrest@aol.com<br>> *Sent:* Thursday, June 26, 2008 11:51 AM<br>> *To:* nsrca-discussion@lists.nsrca.org<br>> *Subject:* Re: [NSRCA-discussion] 2.4Ghz<br>><br>> I've got mixed opinions about the flight log. I flew my<br>> pattern ship all last year using a DX7 and the AR7000 with no<br>> problems. Later I bought the flight log and tested it on the<br>> AR7000. While it showed correctly there were two receivers in<br>> operation, some of the other readings were strange. It turned<br>> out my AR7000 wasn't upgraded to support the flight log. Still<br>> the flight log acted as if it did.<br>><br>> Recently I bought a R921 on e-Bay. I range tested it with the<br>> flight log. The readings were terrible. I sent the R921 back<br>> to Horizon. They could find nothing wrong. When it returned I<br>> tested it again. Still bad readings. Talked to Horizon again.<br>> Was told to try it in a plane. Before doing that, one more<br>> time I range tested it on top of a paper box. Did the exact<br>> same thing with two receivers that I had successfully test<br>> flow in an airplane. This last test, the "bad" receiver had<br>> better numbers than the two "good" ones!<br>><br>> I'm now wondering if these receivers retain some information<br>> after being turned off and this leads to erratic flight log<br>> readings. BTW, someone on one of the discussion lists says<br>> when there is a frame lost it is not counted as an antenna<br>> fade. I don't know if this is true but it does make the math<br>> work. Yes, I've had on occasion more frame losses than antenna<br>> fades.<br>><br>> Allan<br>><br>> In a message dated 6/25/2008 9:20:15 AM Central Daylight Time,<br>> jlkonn@hotmail.com writes:<br>><br>> I am curious what other folk's experience has been with<br>> JR/Spektrum 2.4Ghz.<br>> I have experienced a frame loss when one satelite Rx<br>> showed -0- fades. It's my understanding<br>> this shouldn't happen. I have another 9ch Rx from the<br>> "Great Receiver Giveaway" I'm going to<br>> try but was wondering what others are finding is average<br>> for fades and frame losses per flight?<br>> Thanks!<br>> JLK<br>><br>><br>><br>><br>><br>><br>> **************<br>> Gas prices getting you down? Search AOL Autos for<br>> fuel-efficient used cars.<br>> (http://autos.aol.com/used?ncid=aolaut00050000000007) <br>><br>><br>> ------------------------------------------------------------------------<br>> Introducing Live Search cashback . It's search that pays you back!<br>> Try it Now<br>> <http://search.live.com/cashback/?&pkw=form=MIJAAF/publ=HMTGL/crea=introsrchcashback><br>><br>><br>><br>> ------------------------------------------------------------------------<br>> The other season of giving begins 6/24/08. Check out the i’m <br>> Talkathon. Check it out! <br>> <http://www.imtalkathon.com?source=TXT_EML_WLH_SeasonOfGiving><br>> ------------------------------------------------------------------------<br>><br>> _______________________________________________<br>> NSRCA-discussion mailing list<br>> NSRCA-discussion@lists.nsrca.org<br>> http://lists.nsrca.org/mailman/listinfo/nsrca-discussion<br><br><br /><hr />The other season of giving begins 6/24/08. Check out the i’m Talkathon. <a href='http://www.imtalkathon.com?source=TXT_EML_WLH_SeasonOfGiving' target='_new'>Check it out!</a></body>
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