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Old Mar 04, 2013, 02:57 PM
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Hi Supermat,
yes i meant the "guardian stabilisation expander" for the osd-pro. the same i use in my plane.
if the twinstar where my plane ... i would:

bury the video tx in a wingtip ... cut a pocket, and feed the 3 lines through a small channel to the tx.

use dipoles for video ... a vee on the plane and a ground planar on the base

mount the rc-rx antennas not as a horizontal vee. one vertical (under the belly), one horizontal. most time the vertical is "active" if your tx antenna is upright ... only at sharp bends the horizontal antenna will be active. with your actual position you get a polarisation loss of some db´s. i made the same "antenna-bending" on a futaba-powered plane and raised the range from 1,9 to nearly 3km without any other actions.

cu Thomas
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Old Mar 04, 2013, 03:06 PM
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hI Supermat,

a nice demo what´s happening when the polarisation is matched...
https://www.youtube.com/watch?v=4xF1Fq2wB1I

cu Thomas
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Old Mar 05, 2013, 07:19 AM
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If I understand correctly the demonstration shows that it's better to have the 2 antenna as much as possible on the same plane better than any other situation.
That's why a vertical RC rx antenna (better when looking the ground) is better than an horizontal one.
Correct ?

For next plane I'm planning to add:
- EZUHF Tx and Rx
- OSD Expander RHI
- 3/4 lobes antennas for Vtx and Vrx maybe with some less power.

while for current plane I think you are right and I will try to position at least one of my 2 antennas vertically.
thanks a lot
ciao
supermat
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Old Mar 05, 2013, 07:54 AM
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Quote:
Originally Posted by supermat View Post
If I understand correctly the demonstration shows that it's better to have the 2 antenna as much as possible on the same plane better than any other situation.
That's why a vertical RC rx antenna (better when looking the ground) is better than an horizontal one.
Correct ?

For next plane I'm planning to add:
- EZUHF Tx and Rx
- OSD Expander RHI
- 3/4 lobes antennas for Vtx and Vrx maybe with some less power.

while for current plane I think you are right and I will try to position at least one of my 2 antennas vertically.
thanks a lot
ciao
supermat
Hi Supermat,
yes, the video shows how important the alignement of the tx/rx antennas is.
the radiation pattern of a straight antenna is like a donut, the antenna is the y- axis (through the hole). normally this donut is flat on the basement. that´s the reason why the rx antenna should be mounted facing downwards. normally the plane is above the pilot.

cu Thomas
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Old Mar 07, 2013, 02:44 AM
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Quote:
Originally Posted by supermat View Post
Following above suggestion I've been able to reach 714 mts ... I'm wondering how much I can push further with my Aurora9 and Optima9 receiver.
Here my Video
http://www.youtube.com/watch?v=L4jLMlglksU
Nice video, Mat. Stay high, and you've got a good bit more range. But of course, there's not as much to see and play with up high!
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Old Mar 07, 2013, 01:32 PM
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txs Wazoo, txs Thint
today I received my pass low filter for VTX and I'm going to test again my new 3 lobe antenna (with 4 lobes on the VRx side), doing some range test in advance for the interference problem with the 2.4 RC.
I've also tried to create some distance from the 2 bode RC rx antennas to the fuselage and I hope it will improve a little bit the quality of the RC signal.
I've not been able to do better than this 'cause any re-arrangement of RC rx would oblige me to substitute the fuselage... so.. after next crash I'll definitively do better than this.... hopefully in some time ...
Do you think I should keep the final part of RC Antennas looking at ground (like in the picture) or I can go straight following the wire part ?
thanks for your suggestions.
ciao
Supermat
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Last edited by supermat; Mar 07, 2013 at 02:04 PM.
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Old Mar 07, 2013, 02:29 PM
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Hi Supermat,
i believe that your rc-antennas need a little bit more tuning
mount one of the antennas horizontal to get a better reception during turns with a higher tilt angle. the 2nd antenna is mounted well.
to prevent the active part from bending i always reinforce with a heat-shrink-tube.

cu Thomas

p.s.: finally i found the link on my pc again.
Antennas 101 - Polarization, Diversity & Gain Patterns (27 min 56 sec)
in this animated video the priciples of polarisation, radiation patterns and gain is very well shown. once you recogniced how it works, you´ll be unbeatable
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Old Mar 07, 2013, 03:44 PM
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thanks for the video I'll follow it with attention.
In the meanwhile I've tried to follow your suggestion.
Better in this way ?
thanks
ciao
supermat
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Old Mar 07, 2013, 05:11 PM
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Hi,
next test will go for 1,5km ... or more
pls setup the rth before pushing the limits of the rc. even without the guardian a safe but not so calm rth is possible. see my vid on vimeo
Eagle Tree OSDpro without guardian RTH (4 min 9 sec)

cu Thomas
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Old Mar 08, 2013, 10:47 AM
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thanks,
do you suggest to set it up with rudder or ailerons ? (no more than 1/2 stick)
Do you think it possible to use elevator for/during left-right setup ?
I hate rudder and I would prefer to set it maybe with 1/2 aileron and 1/4 elevator together or something like that...
but I understand if you tell me that rudder without AHI is the easiest and logical choice
ciao
Supermat
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Old Mar 08, 2013, 10:59 AM
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I have several doubt concerning RTH first time usage because the simulator of the Eagletree system with RTH Activation test on the ground is a little bit "artificial" and I'm not 100% sure to have understood the behaviour I will face on the first flight with it.
Correct me if I'm wrong, there is no button for RTH, it has to be "armed" before takeoff, and during the normal flight I should not see "RTH enagaged: RX failsafe detected" (as well as in your video). RTH will be activated automatically after loosing RC signal (behaving as per the setup) and the popup "RTH enagaged: RX failsafe detected" will consequently come up. after that I expect my plane will start moving smoothly back to me.
What I shall expect after it comes back in RC signal range ?
Do I have the control back with RTH always active (and consequently intervening ?)
Do I have to switch RTH off during flight throught the menu after it comes back into RC range and before I take control back?
I'm a little bit confused...
many thanks
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Old Mar 08, 2013, 12:23 PM
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Hi supermat, here are a couple of thoughts:

1) The simulator is there primarily to let you confirm that RTH activates when it should, and that the control surfaces of your plane move in the correct directions during RTH. It does not simulate actual flight conditions necessarily.

2) There are a few methods to test RTH (we never recommend turning off your radio in flight!)
a) What's known as the "Carlyle Method" (can be found by searching this thread, and is also described in the "Setting up RTH with Receivers that Support a Throttle Failsafe" section on page 16 of the manual here. This is the method most people use, and it lets you activate RTH in-flight by just trimming down on your throttle trim.
b) Using the "Test RTH" inflight menu, if you are comfortable accessing menus in-flight.
c) Configuring your radio switch method to "Option C" (see page 12 of the manual) which lets you use one of the radio switch positions to enable RTH testing.
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Old Mar 08, 2013, 02:20 PM
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hi Matthew,
... so much questions need a longer typing
pls forgive my typos or "funny" grammar, my english lessons at school are some years in the past, and my actual practice is spoken english, but with people with another mother tongue than english.

et can handle different causes of rc-link loss. in your case the system will react to a failsafe
rth kicks in 2 seconds after the receiver goes into failsafe. to recognize when a failsafe situation occurs the software seeks an "abnormal" signal on the throttle channel. that means a throttle value below the normal "throttle cut".
to achieve this, the rc-system must be programmed to do so. i don´t know your system, at my rc this is during the binding procedure. at this point you should know how you want to activate a rth at a normal rc reception. there are 2 ways - a switch to aux to activate the "rth test mode" or the cheating of the osd, the "clarlyle-method". in my experience the safer and quicker way is to cheat the osd. if your rctx support switched mixers i prefer this, otherwise you have to use the throttle trim to reach throttle values below normal. the switched mix is easy to program assign a free switch to the mix and mix a value of "negative maximum" to the trottle. control the function with the servo-monitor or a connected servo. when the switch is activated the channel should go below the normal throttle cut position. at my rx this happens even at full throttle, at a futaba of my friend this happens only at throttle positions below half. anyway the activation of a rth takes less than a second. when you store the failsafe this switch or the trim has to be active. storing the failsafe has to be the first action during the setup of rth! those settings are stored during the wizzard asks for switch off the tx. during flight never turn off the tx to reach rth! the chance that the receiver "finds" his transmitter is very low at higher distances than powering up on ground.
for the next actions you have to know what´s going on during rth. first of all rth disengages at the moment the failsafe is gone and you must control the plane again. at the limit of the rc reception it happens that the system toggles between failsafe and normal. to prevent stress in this situation is a good practice to switch to "manual rth" and wait until the plane comes a few hundred meters nearer to home (in an area with stable reception) and then take the controls again disengaging the manual rth.
the most important for rth is the height and throttle management. et knows 2 height parameter; home - that is a user defined circle from home, and cruise - that is the area out of the home circle. for my use, flying in a landscape with hills, i found out that home height at 100m and 300m radius and cruise at 250m are safe. you have to calculate that on autonomous flight all obstacles have to be lower than your plane and that the minimum flying height for civil-planes shall be above your flightpath.
the throttle managemant will cut the throttle over the height to force the plane to glide down. on the height the throttle is on cruise to force the plane to a motor-powered flight on level. if the plane is below the height the throttle is activated with climb. those 3 throttles are asked during the setup-wizzard. its a good practice to find out those throttle positions before doing the wizzard. in your case, a motor-plane, the throttle cut position needs not to be "motor off" choose a position where the plane does a moderate descent. also the climb should not be "full throttle" the position for a moderate climb is the better.
turning during rth must not be like aerobatics, especially without a stabilisation like the guardian the turns shall have 100 to 150m radius. for a safe return a stable flight is more important than the time. at the other hand the turns shall be small enough to defeat a possible sidewind. to find the right deflections for elevator and rudder (no stabilisation) or aileron (with guardian) you need more time than finding the throttle positions. attention: the wizzard only ask for rudder/aileron input, but the elevator is stored at this moment too! because normaly you perform a turn with a mixed input of rudder and elevator to prevent a dive.

for performing a stable and safe rth without stabilisation its absolutelly needed that the plane is well tuned before finding the proper stick positions. the plane should level itself after a turn and there shall be no elevator inputs needed if the throttle is changed. up elevator at low throttle and down elevator at high throttle is an absolute no-go. this must be corrected with shims to correct the motor-angles.

once you have found the stick positions you can do the wizzard and start with the default values. do the tests like in the manual described point per point and correct the values if needed (the different values and their influence on changes are well described in the manual). without the guardian the flight may look like a beginner is steering the plane ... this doesn´t matter - the main goal is to bring the plane home

cu Thomas

edit: hi Bill, nice you´re in this thread i´ve been typing such a long time that i didn´t recognice that you´ve dialed in in the meantime.
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