Mounting location for AR7000 satellite receiver

[TheBum]

Where is everybody mounting the AR7000 satellite receiver on their T-Rex 600Ns? Most advice I've seen says to keep it away from any carbon fiber, but it seems that the only way to do that and keep the two dipole antennas perpendicular is to put it on the tip of the electronics box at the front of the heli (my main receiver will be mounted on the top of the electronics box, toward the rear). Would there be any shadowing issues with doing that?

[george0079]

That's where alot of people are mounting them. No problems......

[Trex mad1]

Ive stuck mine to the frame, exhaust side. With the wires sticking out the front off of the carbon fiber, It works fine like this on my 450 aswell:dontknow

[TheBum]

Side mounting is complicated by the Align frame stiffeners, really limiting where the satellite can go without obstructing screws. Since I now know that people are doing it successfully, I think I'll mount it on the tip of the electronics box as I mentioned. There's a nice flat spot there just about the perfect size.

[brgsstm]

Here is mine. No problems at all :thumbup:

[TheBum]

I hadn't thought of orienting the antenna wires vertically. At least that would further the distance of one of the wires from the frame side. However, wouldn't the muffler tend to obstruct radio waves reaching it, especially the lower wire? My only concerns about putting it where I just said I was planning to put it are that the satellite antenna is just barely at the recommended minimum 2 inches from the main antenna, and I'm wondering how easy it will be to mess up the straightness of the antenna wires when I put the canopy on.

I know I'm probably over-thinking this as I have a tendency to do with most things, but I definitely don't want a radio lock-out at this stage of my learning curve.

Edit: OK, please bear with me as I ramble. I think I found a compromise. If I position the satellite on the frame stiffener rotated 90 degrees from brgsstm's suggested orientation, it will just fit to the right of the top screw and above the middle screw. By orienting it with the cable exiting toward the bottom of the heli, I can get the antenna out from behind the shadow of the muffler.

[brgsstm]

Yeah that would work fine Bum, (feels strange writing that)

Personally I know a lot of other helis have their satellites located as mine with no lockout problems, but I dont see aproblem with how you want to mount it.

FWIW I use the frame stiffeners aswel,

Tom

[boosst]

how about some pigs? I will be mounting mine tonight and havent even thought about it.

[Bobbyk]

You can purchase a longer extension cable and put it on the boom block?

I have mine where Tom has his but on the inside of the frame where the glow plug goes, mine wires sticks out of the bottom canopy where you clip the canopy on the landing skids, works well for me.

Robert

[brgsstm]

how about some pigs? I will be mounting mine tonight and havent even thought about it.

What are pigs?

Tom

[Bobbyk]

I think he meant pics?

[boosst]

yes, pics is what I meant...sorry

[manike]

Side mounting is complicated by the Align frame stiffeners, really limiting where the satellite can go without obstructing screws. Since I now know that people are doing it successfully, I think I'll mount it on the tip of the electronics box as I mentioned. There's a nice flat spot there just about the perfect size.

You can just make mine out, bottom center of the photo.

I mounted it to the frame stiffener with velcro. Stays in place just fine for general flying and 3D (as flow by a friend of mine) not sure about hard 3D with the velcro. It isn't in the way of the screws at all.

Just made sure that the aerial didn't touch the frame and it's all good. You can see how the aerials are vertical and in a different plane to the receiver.

http://i49.photobucket.com/albums/f283/manike/600N-11.jpg

[brgsstm]

yes, pics is what I meant...sorry

sorry i should of worked that out :o

Tom

[TheBum]

I'll definitely be mounting on the left side of the heli, though. I eventually intend to get a CarbSmart, so I'll have to have clearance to the needle valve on the right side.

[Trex mad1]

Mines the same as Brgsstm, but i have faced my wires forward off of the frame.:YeaBaby:

[TheBum]

Got 'er done. Here's what mine looks like.

http://www.helifreak.com/attachment.php?attachmentid=39549&stc=1&d=1203654156

[manike]

Looks good. :thumbup:

[Trex mad1]

Hi TheBum, both your ariels are in the same plane, you need to turn your satelite 90 degrees mate, for best results.:YeaBaby:

[brgsstm]

Hi TheBum, both your ariels are in the same plane, you need to turn your satelite 90 degrees mate, for best results.:YeaBaby:

+1

both are in the horizontal plane in that configuration.

Tom

[TheBum]

I don't see where it really matters. The only way you're going to get antennas such that they're not all in the same plane is if you have three of them. Or, to look at it this way: If I turned the satellite antenna vertical, then both antennas would be in the lateral vertical plane.

The point of having two antennas is to avoid the situation where the transmitter is positioned end-on to a single antenna, which is the weak area of the reception pattern. As long as the two antennas are offset by 90 degrees, regardless of what plane they're in, the goal is accomplished.

[brgsstm]

I think the point of it is that if there is always one in each plane if they are mounted one in the vertical and one in the horizontal. ie nose down or on its side or even inverted. No one is saying you have to do that. It is just what people are commonly suggested to do. you will probably have no problems at all like that. I just prefer to do what the majority of people i ask are doing.

Tom

[TheBum]

I think the point of it is that if there is always one in each plane if they are mounted one in the vertical and one in the horizontal. ie nose down or on its side or even inverted.
I would argue that the same goes if they're both mounted horizontally. Here are the antenna visibility breakdowns for the two configurations, assuming a horizontal lateral orientation of the main antenna and the satellite mounted on the side:

Satellite antenna oriented vertically:
Nose/tail-in: 2 antennas
Side-in: 1 antenna (satellite)
Top/bottom-in: 1 antenna (main)
Satellite antenna oriented horizontally:
Nose/tail-in: 1 antenna (main)
Side-in: 1 antenna (satellite)
Top/bottom-in: 2 antennas
The main reason I'm hesitant to reorient the antenna is that a vertical orientation when mounted on the frame stiffener would put the bottom pole of the antenna partially in the shadow of the muffler in a pure side-in orientation, i.e. when that antenna is the only one visible in either mounting orientation.

I suppose you *could* justify the vertical antenna orientation if you're assuming that you'll be spending more time with the heli in a tail/nose-in orientation than you will in a top/bottom-in orientation, but how much time will you spend in a *pure* nose/tail-in orientation at a distance where radio reception might be an issue? As you say, probably either way will work equally well, it's just whatever you're comfortable with. I'm not one to conform for conformance sake; there has to be a logical reason and I'm willing to listen to logical arguments contrary to mine.

So, is it pulverized yet? :DH

[brgsstm]

I would argue that the same goes if they're both mounted horizontally. Here are the antenna visibility breakdowns for the two configurations, assuming a horizontal lateral orientation of the main antenna and the satellite mounted on the side:


Satellite antenna oriented vertically:Nose/tail-in: 2 antennas

Side-in: 1 antenna (satellite)

Top/bottom-in: 1 antenna (main)Satellite antenna oriented horizontally:Nose/tail-in: 1 antenna (main)

Side-in: 1 antenna (satellite)

Top/bottom-in: 2 antennasThe main reason I'm hesitant to reorient the antenna is that a vertical orientation when mounted on the frame stiffener would put the bottom pole of the antenna partially in the shadow of the muffler in a pure side-in orientation, i.e. when that antenna is the only one visible in either mounting orientation.

I suppose you *could* justify the vertical antenna orientation if you're assuming that you'll be spending more time with the heli in a tail/nose-in orientation than you will in a top/bottom-in orientation, but how much time will you spend in a *pure* nose/tail-in orientation at a distance where radio reception might be an issue? As you say, probably either way will work equally well, it's just whatever you're comfortable with. I'm not one to conform for conformance sake; there has to be a logical reason and I'm willing to listen to logical arguments contrary to mine.

So, is it pulverized yet? :DH


I'm not sure I get you? If the aeriels are in the same orientation to begin with then they will be in the same orientation no matter what position the heli is in?

You cannot cover both planes with both the satellite and the main antennae in the same plane. simple.

If you mount them in different planes there will always be one in one plane and one in another. I answered a question that YOU asked. If you do not like the answer then just ignore it. It is up to you what you do with the information you are given on this site.

The logical reason that you are looking for is what I have already said. Spektrum themselves advise having the satellite and main receiver antennae in different planes.

There will always be times whem both the main and satellite rx's are shadowed by the exhaust ie a climbing right turn from right to left. this doesnt mean that we dont fly climbing right turns though.

[TheBum]

That's just it. My antennas are not both in the same orientation: one is pointing side-to-side and the other is pointing forward and backward. I don't know, maybe the photo is at a weird angle or something and people are seeing both antennas pointing forward and backward, but your comment about seeing them in the horizontal plane makes that seem unlikely.

Let's consider this strictly from a geometry standpoint and think of the antennas as two lines and eliminate the displacement aspect, i.e. they intersect. 3-dimensional geometry dictates that *any* two non-parallel intersecting lines form a plane, regardless of the direction they point in 3-dimensional space. Draw a '+' on a sheet of paper and lay it on a table: that's my antenna geometry. Now, take that same piece of paper and hold it vertically, with the sides of the paper representing the front/back of the heli: that's the geometry you're using. Nothing I'm saying contradicts Spektrum's recommendations.