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Need your critics on antenna planing

_Alex_

Member
hi all,

now i am planning my anntenas and placement. I woulf appreciate your critics and suggestions.

I am planing to use 2 x G3X, GTN 650 Xi, G5, GMC 507, GTR 225A, GMA 245 as well as GSU 25, GMU 11, GTP 59, GEA 24, GAD 13, GAD 29, GTX 35R, PowerFLARM Fusion

Transponder RAMI AV-74, or Deltapop Ultra Low Drag Transponder Antenna bottom skin of tailcone, 3 feet from tie down
DME RAMI AV-74 ??????
ADS-B In RAMI AV-74, or Deltapop Ultra Low Drag Transponder Antenna Under right passenger sit
ADS-B OUT RAMI AV-74, or Deltapop Ultra Low Drag Transponder Antenna Under left passanger sit
PowerFLARM-A RAMI AV-75 Right wing bottom skin
PowerFLARM-B RAMI AV-75 Left wing bottom skin
VOR/LOC/GS RAMI AV-525 On top of vertical stabilizer
COM1 RAMI AV-17, or Deltapop VHF Com Antenna Under pilot sit
COM2 RAMI AV-17, or Deltapop VHF Com Antenna Under copilot sit
GPS for G5 GA 26C BNC Under windshield
GPS for PowerFLARM GA 26C BNC Under windshield
GPS for GTN 650 xi GA 35 On top of tailcone just before baggage compartement, 4 inch to the right from center line
GPS for PFD GA 35 On top of tailcone just before baggage compartement, 4 inch to the left from center line
ELT ELT, ACK 406 MHZ on top of tailcone 1,5 feet from vertical stabilizer (just above the GMU 11)
3G (Mobile data) Antena Deltapop UWB Data Antenna ??????
Marker Beakon??? RAMI AV-569 ??????

Do i really need for Transponder, ADS-b out, ADSB-In three antennas?
 
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Upgrade to the GTX 45R and then you'll get Mode S, ADSB-In & Out all in one box, total integration with G3X and only one antenna -- Use the DP Low Drag for antenna. If diversity is needed for your airspace then change to GTX 345 D model and put another DP low drag antenna on the top of the fuse.

Don't see a need for the Powerflarm system, but that's me...

No need for DME antenna -- you don't list a receiver

No need for Marker Beacon antenna -- you don't list a receiver (GMA 245 doesn't have a marker receiver)

3G antenna pairs with what modem?
 
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Critics?? OK I'll jump in..

Add about 20 HP to drag that thing through the air.:eek: Lordy, that's a lot of antennas. :p
 
Upgrade to the GTX 45R and then you'll get Mode S, ADSB-In & Out all in one box, total integration with G3X and only one antenna -- Use the DP Low Drag for antenna. If diversity is needed for your airspace then change to GTX 345 D model and put another DP low drag antenna on the top of the fuse.

Don't see a need for the Powerflarm system, but that's me...

No need for DME antenna -- you don't list a receiver

No need for Marker Beacon antenna -- you don't list a receiver (GMA 245 doesn't have a marker receiver)

3G antenna pairs with what modem?

Hi Brian, This was a really good one "Upgrade to the GTX 45R and then you'll get Mode S, ADSB-In & Out all in one box"

- I am going to implement PowerFLARM to increase traffic awareness. Most small flying devices are equipped with powerFLARM here in Europe. ADS-B is installed mostly on a bigger machines only. PowerFLARM works on a frequency 902.2 – 927.8 MHz. There is also a DIY light version of PowerFLARM solution, which i possibly will use.

- DME might be a requirement for IFR certification here in Germany. I need to investigate on that

- I would install the Marker Beacon antenna if i choose PMA8000Bti instead of GMA 245. But not decided yet.

- 3G antenna might be overkill. I think will not need this may be.
 
Critics?? OK I'll jump in..

Add about 20 HP to drag that thing through the air.:eek: Lordy, that's a lot of antennas. :p

yep Robert, fully agree. RV-10 is a powerful one, but why i should burn avgas just to drag some unnecessary antennas?

Thank you.
 
Some thoughts:
- There is no reason to put your VOR/LOC/GS antenna on top of the VS. Put it in the right wingtip. It works well beyond any practical range that you will want to use it for.
- Marker Beacon - if you really want to install the receiver the MB antenna is trivial - as in the signal points straight up and is so strong you need close to nothing for an antenna, and the best MB antenna ever made will not provide any advantage. On the last plane I put one in the antenna connected to a bulkhead BNC connector on the firewall, the antenna was made from a ~36” piece of wire I had laying around. The wire connected via a matching BNC fitting, the fitting having a couple of inches of coax in it, then the wire spliced to the coax center conductor. No connection to the coax shield on the antenna side. A few tie wraps to secure the wire to hoses and such across the bottom of engine and good to go. I can report I pick up the marker beacon when flying at altitude of the very few airports that still use these things. The current RVs do not have a marker beacon receiver.
- If anything like the US, the 3G mobile data is not going to work while flying. I’d skip this.
- DME is a waste of time and money with a GTN-650.

Carl
 
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Some thoughts:
- There is no reason to put your VOR/LOC/GS antenna on top of the VS. Put it in the right wingtip. It works well beyond any practical range that you will want to use it for.
- Marker Beacon - if you really want to install the receiver the MB antenna is trivial - as in the signal point straight up and is so strong you need close to nothing for an antenna, and the best MB antenna ever made will not provide any advantage. On the last plane I put one in the antenna connected to a bulkhead BNC connector on the firewall, the antenna was made from a ~36” piece of wire I had laying around. The wire connected via a matching BNC fitting, the fitting having a couple of inches of coax in it, then the wire spliced to the coax center conductor. No connection to the coax shield on the antenna side. A few tie wraps to secure the wire to hoses and such across the bottom of engine and good to go. I can report I pick up the marker beacon when flying at altitude of the very few airports that still use these things. The current RVs do not have a marker beacon receiver.
- If anything like the US, the 3G mobile data is not going to work while flying. I’d skip this.
- DME is a waste of time and money with a GTN-650.

Carl

Thanks Carl,

actually i am thinking what i can do with assembled tailcone as long i am waiting for my QBs, ordered 2 months ago. That`s why the idea with VOR antenna in VS. But to have it in the wing tip seems to be a better one, since it reduces also a drag. I will skip Marker Beakon, G3, and DME.. It can be installed later if really needed.

Now my list looks more reasonable:

- Transponder/ADS-B In/ADS-B OUT Deltapop Ultra Low Drag Transponder Antenna bottom skin of tailcone, 3 feet from tie down
VOR/LOC/GS Bob Archer In the Wingtip
COM1 Deltapop VHF Com Antenna Under right passenger sit
COM2 Deltapop VHF Com Antenna Under left passanger sit
GPS for G5 GA 26C BNC Under windshield
GPS for PowerFLARM GA 26C BNC Under windshield
GPS for GTN 650 xi GA 35 On top of tailcone just before baggage compartement, 4 inch to the right from center line
GPS for PFD GA 35 On top of tailcone just before baggage compartement, 4 inch to the left from center line
ELT ELT, ACK 406 MHZ on top of tailcone 1,5 feet from vertical stabilizer (just above the GMU 11)
 
A couple of different opinions to some of the above based on my research. This is what I did on my RV-10:

I installed my VOR/ILS antenna using a cat whisker antenna from RAMI at the top of my VS. I have heard too may people say that placing it in a wing tip has resulted in signal loss during approach turns due to shielding of the aircraft during the turn.

I installed one bent COM antenna from RAMI under the fuselage behind the baggage bulk head, and the other COM antenna on the top of the tail cone. The antenna below the tail cone doesn't always work well when on the ground, but can be stronger than the one on top when cruising.

I used a single antenna with a GTX 45R transceiver for Xponder/ADS-B out/ADS-B in. I used a stubby rod antenna from RAMI for this and have it coming up in the center tunnel. Try to place it where it is as far as practical from all 3 landing gear legs, as they can shield the antenna, but also be aware of the Garmin coax lengths (min and max) when locating it.

I placed the 2 Garmin GPS antennas on the tail cone, offset from each other in both the longitudinal and latitudinal directions. You want to keep as much distance between them as you have space for, since one of the failure modes of these antennas (they have electronics built into the antenna) is oscillation with significant RFI with can disable the other GPS antenna if it is nearby.

I also installed the ELT antenna on the tail cone near the VS, with spacing in front of the VS per the ELT mfg. recommendations.

No antennas installed on top of the fiberglass cabin top per discussion with Van's, as they very firmly told me there should be NO additional holes drilled in the top that are not specified in the plans, since the cabin top is a key structural element to protect passengers in the event of a roll-over.

It was recommended to me by Aerotronics to try the G5 using just the internal antenna within the G5. I tried it and works beautifully for me. If it causes problems, you can always add the small puck sitting on top of the glare shield inside the cabin later.

Keep longitudinal distances between the antennas as far apart as possible while still maintaining adequate ground plane around each antenna. Garmin has a document with their view of minimum distances (written for certified aircraft).

This question comes up about every 1-2 years, and there are always of number of differing opinions in response. I'm not saying that I'm right and the others are wrong, as many builders have used different configurations successfully. Just offering how I implemented mine and some of the reasons/logic for why. I guess I need to develop a clean single page pdf showing all dimensioned locations to offer in response, but I'm away from home/hanger now and can't currently access my sketches put something like that together.

Hope this helps a little without further adding to the confusion.
 
GPS for PFD GA 35 On top of tailcone just before baggage compartement, 4 inch to the left from center line

Alex,

As explained on page 23-2 of the current Rev. AP G3X Touch installation manual, you can use a GA 26C on the glareshield or a GA 56 on the top of the aircraft for a GDU 4XX antenna.

You cannot use a GA 35 antenna on a GDU 4XX.

Steve
 
Guten Tag Alex

The GA 35 doesn't work with the G3X. I think you'll need a GA 26C, which is mounted inside the cabin, but take a look at the installation manual.

If you do fit DME, the antenna goes underneath, preferably towards the front but it has to be 6 ft (1.8m) from the ADS-B antennas, so it's getting busy down there.

In Europe, a PLB is permitted instead of an ELT and most people seem to go for the PLB.

Having the transponder antenna that far back might be a problem (I don't know) on approaches where the aircraft has a very nose down attitude. Try and find someone who has that location to check.

The last I heard, it was not permitted to fly amateur build aircraft IFR in Germany but, if that has changed, I be keen to have a link to the relevant regulation.

I'd consider swapping the GTN650/GTR225 combination for a GNC355/GNC255, as that would give you independent IFR capable nav boxes and save a bunch of cash. However, you do lose a few high end IFR features so it comes down to personal choice.
 
The GTX 45R is the way to go. I recommend the Comant CI 105 blade antenna. It’s a small blade antenna that does both transponder and ADSB so one antenna needed instead of two. I located the antenna (underneath) under the pilots seat pan and forward of the spar. If your installing the G3X touch MFD in the standard co pilot position, then you can install the transponder rack in in the sub panel directly behind the MFD. You align the rack with the MFD cut out on the panel. Makes for easy access and removal of the transponder. Also the face of the 45R is where the Blue tooth transmits from so you get excellent Blue tooth signal in the cabin.

I have the GMA 245 and it’s great, but note it does not have a maker beacon. Not sure or your Regulations, but here the GPS can be used in place of the OM and MM. If you need a marker beacon installed then you need to go to the GMA 345.

My comm one and two are mounted below the rear seat pans, as outboard on each side as possible. Made an access panel on the left and right seat pan panels for access to the antennas. Your aft of the landing gear no no chance of any interference.
 
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I also went with Comant, but instead of getting the certified antenna, use the E Series. I assume it's the exact same antenna, but since it's not certified, it's cheaper.

Aircraft Spruce carries them.


Depending on your choice of overhead console, you may be able to squeeze a GPS antenna or two inside the overhead.
 
hi all,


PowerFLARM-A RAMI AV-75 Right wing bottom skin
PowerFLARM-B RAMI AV-75 Left wing bottom skin

Can you explain why you want the FLARM A and B Antenna both below the aircraft?

Normally for the Flarm you have 3 (or 4) antennas, 1x FLARM (A), 1x ADSB, 1x GPS. But for metallic aircraft they recommend a second FLARM (B) antenna to be installed below the aircraft.

I did exactly this and have now the FLARM A, ADSB and GPS Antenna in the cockpit and the FLARM B below the fuselage.

You can see both the FLARM A and ADSB Antenna next to the rollbar in this picture:
https://vansairforce.net/community/attachment.php?attachmentid=2252&d=1599724653

The FLARM GPS antenna sits in the middle of the glareshield and left and right of it are the two GA-26 antennas for the G3X and G5

Cheers Yves
 
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EASA has NO requirement for IFR certification. NCO.

In Europe (EASA-countries) there is NO requirement for IFR-certification.
It is entirely up to the pilot to decide what equipment that is required for the route to be flown.
The regulation NCO.IDE.A.190 deals with COM equipment.
Certain airspace may require two COM-radios. Ref AIP.
The regulation NCO.IDE.A.195 deals with NAV equipment.
COM and NAV requirement depends on the airspace to be used. Ref AIP.
NAV equipment should ensure that , in the event of the failure of one item
of equipment at any stage of the flight, the remaining equipment shall allow safe navigation.

Good Luck
 
Antenna Placement...

Not sure, but I think you can add a few more antennas...
 

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FWIW, I put my VOR/LOC/GS vee dipole inside the cabin top, also my com 2 quarter wave monopole. All made of copper foil tape (and coaxial cable balun for the VOR) and impossible to spot without a strong light shining through the composite. Zero drag. Minimal weight, almost zero cost.

Full disclosure: the nav antenna set up has not been tested in flight; GPS is too easy and fun to go messing with VORs, until IFR training starts someday.
 
Thanks all for providing your feedback, which helps also to other inexperienced builders like me. Actually i did not decided finally on the avionics yet, but it is important to know there is a solutions for such things like one antenna for Transponder/ADS-B IN/ADS-B OUT.
@Gustav, "In Europe (EASA-countries) there is NO requirement for IFR-certification". This point is very interesting. Is it related also to the experimentals? Would be great. So i will not need a DME equipment and marker beacon.
@Yves. The FLARM equipment make a flying Christmas tree from the plane. Your solution seems to be reasonable. I know there is no regulatory requirement for that, but i will install it anyway to be more secure in European airspace. Dont know yet which solution.
 
but it is important to know there is a solutions for such things like one antenna for Transponder/ADS-B IN/ADS-B OUT.
.

I’m not sure about European rules, but:
1. You don’t need a separate antenna for ADSB-out because the signal is coming directly from your transponder. A mode S-ES transponder is both a transponder and an adsb-out device. (In the US there is the UAT option, but not in Europe.)
2. In the US ADSB-in is optional. While you can get a transponder with built in ADSB-in, it is relatively expensive, as the receiver electronics must be protected from the high power transponder transmissions. Much less expensive to buy a stand-alone, uncertified (if allowed in Europe) adsb-in box. A small antenna glued to the fiberglass door post in the -10 works well. Choose a receiver that is compatible with whatever you are going to use to display the data. Of course if the display is Garmin, you will be forced to buy a Garmin adsb-in box, which is more expensive than others. If you want/get a wifi connection to an iPad, again consider what software is needed to show traffic there. Think in terms of the entire system.
 
The situation in Europe is more complex than that. EASA doesn't regulate amateur built aircraft but instead, they are regulated by each individual country. Each country can set it's own rules. The reference that I have for Germany comes from the FAQ page of the OUV (approximately the EAA in Germany). This is what it says:

Was sind die Beschränkungen für Selbstbauflugzeuge in der “Beschränkte Sonderklasse”?
[...] Es darf nur am Tag geflogen werden, nicht bei Nacht und nicht IFR.


My translation of that is:
What are the limitations of self-built aircraft in the "restricted special class"? [...] It may only be flown in the day, not at night and not IFR.

Of course, I would love it to be different but, if that's the way it is, it might influence your avionics plans.
 
In Europe (EASA-countries) there is NO requirement for IFR-certification.
It is entirely up to the pilot to decide what equipment that is required for the route to be flown.
The regulation NCO.IDE.A.190 deals with COM equipment.
Certain airspace may require two COM-radios. Ref AIP.
The regulation NCO.IDE.A.195 deals with NAV equipment.
COM and NAV requirement depends on the airspace to be used. Ref AIP.
NAV equipment should ensure that , in the event of the failure of one item
of equipment at any stage of the flight, the remaining equipment shall allow safe navigation.

Good Luck

Yes and no... unfortunately experimentals / homebuilts do not necessarily follow the EASA rules and the rules are made by each country individually...

I also thought PART NCO is applicable and installed a Garmin GNC-255 (as well as the required lights) in my RV-8 to be able to fly at least at night..

But no, the swiss authorities (and yes we are within EASA but not EU) do not allow me to fly at night...
 
@Yves. The FLARM equipment make a flying Christmas tree from the plane. Your solution seems to be reasonable. I know there is no regulatory requirement for that, but i will install it anyway to be more secure in European airspace. Dont know yet which solution.

Yes it makes a lot of sense to install FLARM in a european aircraft. I did not have it in my old (certified) plane and now in the RV-8 I get notifications of other planes nearly every flight and sometimes I only see them after some time... Without it I would not be aware of them... Thus a huge safety aspect..
 
I am using the GMA345 instead of GMA245 to get a MB receiver. It is not well integrated with the G3X but I don't care, the physical buttons on the unit work for me. It is fully featured with ATC replay, Bluetooth music etc.
I use the GNX375 to cover (secondary) GPS, transponder and ADSB in and out.
Concerning GPS antennas I noticed that the certified 650 and 375 are not very sensitive, you should stick to the instructions and mount the antennas where they should go. The G5 and GDU460 have very sensitive GPS receivers and they can stay inside. The G5's internal GPS antenna might also already be good enough, try that out first.
 
The situation in Europe is more complex than that. EASA doesn't regulate amateur built aircraft but instead, they are regulated by each individual country. Each country can set it's own rules. The reference that I have for Germany comes from the FAQ page of the OUV (approximately the EAA in Germany). This is what it says:

Was sind die Beschränkungen für Selbstbauflugzeuge in der “Beschränkte Sonderklasse”?
[...] Es darf nur am Tag geflogen werden, nicht bei Nacht und nicht IFR.


My translation of that is:
What are the limitations of self-built aircraft in the "restricted special class"? [...] It may only be flown in the day, not at night and not IFR.

Of course, I would love it to be different but, if that's the way it is, it might influence your avionics plans.

Thanks Raiz.. Important point.. I know the people from OUV.. They are very supportive, and do they right job at the best. But anyway, i did not clearly understood yet the authority of OUV as a group. Does it have the authority to setup the rules about IFR regulations for experimental planes in Germany?
 
Alex, as I understand it, the LBA retains the rule making responsibility but they delegate the implementation to the OUV. The OUV will be happy to tell you how it works.
 
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