Topics

ADSB In - Classic Cozy 3 Antenna Placement Experience

Richard Sessions
 

Campers,

I know there has been a lot of discussion on the ADSB-In antenna placements a few months back, but curious to see what people are getting good results with in
a Classic Cozy 3 now that there has been a little more time and likely more experience.

I know there was the slot antenna and others, but I am thinking a 13"ish square foil for the dipole under the left thigh support.  I know it is a projection and subject to ridicule, but pretty simple and not a lot of changes / structure in the back seat area.

I am hooking up to a Dynon HDX system in a panel upgrade and it is about the last thing I have when my newly repaired ADAHRs gets back (static port failure....).

Feel free to contact me off line as I am sure most feel we have done this to death.

Thanks!
Richard
Richard Sessions, Cozy 3 N9455 (William Chorley builder if anyone has anything on it)
Houston's Ellington Field (KEFD) - Go RAFE!
rtsessions@..., 281-467-2432 (leave a message with all the spam....)

Del Schier
 

Hi Richard,  You may not be aware of the S53MV annular slot transponder antenna for composite aircraft. It is easy and cheap to make and works with no holes in the airplane; just set it on the floor.  It has the advantage that it has about 6 dB gain over a ¼ wave rod or ½ wave dipole giving approximately four times the signal strength. 

 

Note that the original designer told me his design may not work at 978 MHz for ADS-B UAT and it didn’t.  I scaled the antenna, see attached, so that it was optimized for 978.  If you are going to use it with a 1090 ES ADS-B or Mode C transponder you should use the drawings from the designer, no my attached drawing. 

 

There are at least a dozen people using these in their canards and to my knowledge they are all working well, provided they were made accurately (+- 1/16”).  One guy sent me one to test that he had almost ½” errors and that one did not work. 

 

Del Schier

Cozy IV N197DL

Cannon Creek Airpark 15FL

 

 

 

From: members@canardzone.groups.io <members@canardzone.groups.io> On Behalf Of Richard Sessions
Sent: Sunday, June 21, 2020 11:40 PM
To: members@canardzone.groups.io
Subject: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Campers,

I know there has been a lot of discussion on the ADSB-In antenna placements a few months back, but curious to see what people are getting good results with in
a Classic Cozy 3 now that there has been a little more time and likely more experience.

I know there was the slot antenna and others, but I am thinking a 13"ish square foil for the dipole under the left thigh support.  I know it is a projection and subject to ridicule, but pretty simple and not a lot of changes / structure in the back seat area.

I am hooking up to a Dynon HDX system in a panel upgrade and it is about the last thing I have when my newly repaired ADAHRs gets back (static port failure....).

Feel free to contact me off line as I am sure most feel we have done this to death.

Thanks!
Richard
Richard Sessions, Cozy 3 N9455 (William Chorley builder if anyone has anything on it)
Houston's Ellington Field (KEFD) - Go RAFE!
rtsessions@..., 281-467-2432 (leave a message with all the spam....)

berkut13
 

 

ADS-B in (receive only) antenna does not require a ground plane of any size.   A simple TED stick/ball transponder antenna on a bracket will do nicely.  Just mount it low in the fuselage with the best possible downward conical exposure (not blocked by metal objects) for the best results.

https://www.aircraftspruce.com/catalog/avpages/ted_transponder.php

 

 

For ADS-B out (transmit & receive), you will need a ground plane and the appropriate size antenna for the system (1090ES or UAT) you are using.  A UAT system would use a slightly longer antenna and larger ground plane than the traditional 1090ES transponder type due to its slightly lower 978 frequency.

https://www.aircraftspruce.com/pages/av/antenna_adsb/monopole11-13561.php

 

 

For reference:

120mm square ground plane for transponders (1090ES)

130mm square ground plane for UAT systems and appropriate antenna

Put the antenna in the center, .020 aluminum is fine for this use, radius the corners ¼” or so

 

I’ve installed several…all work very well.

 

-James

Berkut/Race13

 

 

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Richard Sessions
Sent: Sunday, June 21, 2020 10:40 PM
To: members@canardzone.groups.io
Subject: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Campers,

I know there has been a lot of discussion on the ADSB-In antenna placements a few months back, but curious to see what people are getting good results with in
a Classic Cozy 3 now that there has been a little more time and likely more experience.

I know there was the slot antenna and others, but I am thinking a 13"ish square foil for the dipole under the left thigh support.  I know it is a projection and subject to ridicule, but pretty simple and not a lot of changes / structure in the back seat area.

I am hooking up to a Dynon HDX system in a panel upgrade and it is about the last thing I have when my newly repaired ADAHRs gets back (static port failure....).

Feel free to contact me off line as I am sure most feel we have done this to death.

Thanks!
Richard
Richard Sessions, Cozy 3 N9455 (William Chorley builder if anyone has anything on it)
Houston's Ellington Field (KEFD) - Go RAFE!
rtsessions@..., 281-467-2432 (leave a message with all the spam....)

Phil Kriley
 

I had severe interference with my comm radios after having a Garmin 375 installed.  At full throttle the transmit light would flicker brightly and there was a loud buzz in the headset.  Switching to Comm 2 was no help.  The 375 was connected to a spike antenna (for the transponder functio) that had been used for my old transponder which was removed, as the 375 has its own transponder, GPS, and ADS-B in and out.  After several weeks of troubleshooting, including replacing both PTT switches, alternator rebuild, etc. etc. it was found that using a Garmin antenna and moving it to the rear of the plane next to the scoop solved the problem.

FWIW

Phil Kriley
Flying N93CF again!  Yeah!

On Jun 22, 2020, at 1:04 PM, berkut13 <berkut13@...> wrote:

 

ADS-B in (receive only) antenna does not require a ground plane of any size.   A simple TED stick/ball transponder antenna on a bracket will do nicely.  Just mount it low in the fuselage with the best possible downward conical exposure (not blocked by metal objects) for the best results.

https://www.aircraftspruce.com/catalog/avpages/ted_transponder.php

 

 

For ADS-B out (transmit & receive), you will need a ground plane and the appropriate size antenna for the system (1090ES or UAT) you are using.  A UAT system would use a slightly longer antenna and larger ground plane than the traditional 1090ES transponder type due to its slightly lower 978 frequency.

https://www.aircraftspruce.com/pages/av/antenna_adsb/monopole11-13561.php

 

 

For reference:

120mm square ground plane for transponders (1090ES)

130mm square ground plane for UAT systems and appropriate antenna

Put the antenna in the center, .020 aluminum is fine for this use, radius the corners ¼” or so

 

I’ve installed several…all work very well.

 

-James

Berkut/Race13

 

 

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Richard Sessions
Sent: Sunday, June 21, 2020 10:40 PM
To: members@canardzone.groups.io
Subject: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Campers,

I know there has been a lot of discussion on the ADSB-In antenna placements a few months back, but curious to see what people are getting good results with in
a Classic Cozy 3 now that there has been a little more time and likely more experience.

I know there was the slot antenna and others, but I am thinking a 13"ish square foil for the dipole under the left thigh support.  I know it is a projection and subject to ridicule, but pretty simple and not a lot of changes / structure in the back seat area.

I am hooking up to a Dynon HDX system in a panel upgrade and it is about the last thing I have when my newly repaired ADAHRs gets back (static port failure....).

Feel free to contact me off line as I am sure most feel we have done this to death.

Thanks!
Richard
Richard Sessions, Cozy 3 N9455 (William Chorley builder if anyone has anything on it)
Houston's Ellington Field (KEFD) - Go RAFE!
rtsessions@..., 281-467-2432 (leave a message with all the spam....)

"michaelagarmon@gmail.com
 

James,
Do you extend the stick ball outside of the fuselage for either frequency? Is the fiberglass transparent at these frequencies? 
Thanks 
Michael Garmon
Cozy Mk IV
Houston, TX

On Jun 22, 2020, at 12:04 PM, berkut13 <berkut13@...> wrote:



 

ADS-B in (receive only) antenna does not require a ground plane of any size.   A simple TED stick/ball transponder antenna on a bracket will do nicely.  Just mount it low in the fuselage with the best possible downward conical exposure (not blocked by metal objects) for the best results.

https://www.aircraftspruce.com/catalog/avpages/ted_transponder.php

 

 

For ADS-B out (transmit & receive), you will need a ground plane and the appropriate size antenna for the system (1090ES or UAT) you are using.  A UAT system would use a slightly longer antenna and larger ground plane than the traditional 1090ES transponder type due to its slightly lower 978 frequency.

https://www.aircraftspruce.com/pages/av/antenna_adsb/monopole11-13561.php

 

 

For reference:

120mm square ground plane for transponders (1090ES)

130mm square ground plane for UAT systems and appropriate antenna

Put the antenna in the center, .020 aluminum is fine for this use, radius the corners ¼” or so

 

I’ve installed several…all work very well.

 

-James

Berkut/Race13

 

 

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Richard Sessions
Sent: Sunday, June 21, 2020 10:40 PM
To: members@canardzone.groups.io
Subject: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Campers,

I know there has been a lot of discussion on the ADSB-In antenna placements a few months back, but curious to see what people are getting good results with in
a Classic Cozy 3 now that there has been a little more time and likely more experience.

I know there was the slot antenna and others, but I am thinking a 13"ish square foil for the dipole under the left thigh support.  I know it is a projection and subject to ridicule, but pretty simple and not a lot of changes / structure in the back seat area.

I am hooking up to a Dynon HDX system in a panel upgrade and it is about the last thing I have when my newly repaired ADAHRs gets back (static port failure....).

Feel free to contact me off line as I am sure most feel we have done this to death.

Thanks!
Richard
Richard Sessions, Cozy 3 N9455 (William Chorley builder if anyone has anything on it)
Houston's Ellington Field (KEFD) - Go RAFE!
rtsessions@..., 281-467-2432 (leave a message with all the spam....)

berkut13
 

Glass is radio transparent for the equipment we use in GA and I don’t extend the antenna outside the fuselage skin unless there is a physical height issue (like under the front thigh support).   When I do, it is only partly outside the skin.

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of "michaelagarmon@...
Sent: Monday, June 22, 2020 6:43 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

James,

Do you extend the stick ball outside of the fuselage for either frequency? Is the fiberglass transparent at these frequencies? 
Thanks 

Michael Garmon

Cozy Mk IV

Houston, TX



On Jun 22, 2020, at 12:04 PM, berkut13 <berkut13@...> wrote:



 

ADS-B in (receive only) antenna does not require a ground plane of any size.   A simple TED stick/ball transponder antenna on a bracket will do nicely.  Just mount it low in the fuselage with the best possible downward conical exposure (not blocked by metal objects) for the best results.

https://www.aircraftspruce.com/catalog/avpages/ted_transponder.php

 

 

For ADS-B out (transmit & receive), you will need a ground plane and the appropriate size antenna for the system (1090ES or UAT) you are using.  A UAT system would use a slightly longer antenna and larger ground plane than the traditional 1090ES transponder type due to its slightly lower 978 frequency.

https://www.aircraftspruce.com/pages/av/antenna_adsb/monopole11-13561.php

 

 

For reference:

120mm square ground plane for transponders (1090ES)

130mm square ground plane for UAT systems and appropriate antenna

Put the antenna in the center, .020 aluminum is fine for this use, radius the corners ¼” or so

 

I’ve installed several…all work very well.

 

-James

Berkut/Race13

 

 

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Richard Sessions
Sent: Sunday, June 21, 2020 10:40 PM
To: members@canardzone.groups.io
Subject: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Campers,

I know there has been a lot of discussion on the ADSB-In antenna placements a few months back, but curious to see what people are getting good results with in
a Classic Cozy 3 now that there has been a little more time and likely more experience.

I know there was the slot antenna and others, but I am thinking a 13"ish square foil for the dipole under the left thigh support.  I know it is a projection and subject to ridicule, but pretty simple and not a lot of changes / structure in the back seat area.

I am hooking up to a Dynon HDX system in a panel upgrade and it is about the last thing I have when my newly repaired ADAHRs gets back (static port failure....).

Feel free to contact me off line as I am sure most feel we have done this to death.

Thanks!
Richard
Richard Sessions, Cozy 3 N9455 (William Chorley builder if anyone has anything on it)
Houston's Ellington Field (KEFD) - Go RAFE!
rtsessions@..., 281-467-2432 (leave a message with all the spam....)

berkut13
 

… I would also point out that type of mounting would only be justified for a transmitter (ADS-B out) system and a ground plane.  Receive only (ADS-B in) can be mounted just about anywhere, facing up or down as long as it is vertically polarized and has a good “view” of the ground.

 

A couple of weeks ago, I installed this antenna in a Velocity – echoUAT system.  Plenty of space, so no external exposure needed.

Albeit, this is a temporary solution until the panel is upgraded later this year with fully integrated 1090ES triple G3X/750Xi/autopilot setup.  Wheeee!

 

-James

 

 

From: berkut13@... [mailto:berkut13@...]
Sent: Monday, June 22, 2020 10:32 PM
To: 'members@canardzone.groups.io'
Subject: RE: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Glass is radio transparent for the equipment we use in GA and I don’t extend the antenna outside the fuselage skin unless there is a physical height issue (like under the front thigh support).   When I do, it is only partly outside the skin.

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of "michaelagarmon@...
Sent: Monday, June 22, 2020 6:43 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

James,

Do you extend the stick ball outside of the fuselage for either frequency? Is the fiberglass transparent at these frequencies? 
Thanks 

Michael Garmon

Cozy Mk IV

Houston, TX

 

On Jun 22, 2020, at 12:04 PM, berkut13 <berkut13@...> wrote:



 

ADS-B in (receive only) antenna does not require a ground plane of any size.   A simple TED stick/ball transponder antenna on a bracket will do nicely.  Just mount it low in the fuselage with the best possible downward conical exposure (not blocked by metal objects) for the best results.

https://www.aircraftspruce.com/catalog/avpages/ted_transponder.php

 

 

For ADS-B out (transmit & receive), you will need a ground plane and the appropriate size antenna for the system (1090ES or UAT) you are using.  A UAT system would use a slightly longer antenna and larger ground plane than the traditional 1090ES transponder type due to its slightly lower 978 frequency.

https://www.aircraftspruce.com/pages/av/antenna_adsb/monopole11-13561.php

 

 

For reference:

120mm square ground plane for transponders (1090ES)

130mm square ground plane for UAT systems and appropriate antenna

Put the antenna in the center, .020 aluminum is fine for this use, radius the corners ¼” or so

 

I’ve installed several…all work very well.

 

-James

Berkut/Race13

 

 

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Richard Sessions
Sent: Sunday, June 21, 2020 10:40 PM
To: members@canardzone.groups.io
Subject: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Campers,

I know there has been a lot of discussion on the ADSB-In antenna placements a few months back, but curious to see what people are getting good results with in
a Classic Cozy 3 now that there has been a little more time and likely more experience.

I know there was the slot antenna and others, but I am thinking a 13"ish square foil for the dipole under the left thigh support.  I know it is a projection and subject to ridicule, but pretty simple and not a lot of changes / structure in the back seat area.

I am hooking up to a Dynon HDX system in a panel upgrade and it is about the last thing I have when my newly repaired ADAHRs gets back (static port failure....).

Feel free to contact me off line as I am sure most feel we have done this to death.

Thanks!
Richard
Richard Sessions, Cozy 3 N9455 (William Chorley builder if anyone has anything on it)
Houston's Ellington Field (KEFD) - Go RAFE!
rtsessions@..., 281-467-2432 (leave a message with all the spam....)

Steve Stearns
 

I made a wideband dipole out of brass tubing and mounted it on the back of the headrest (Longeze).  I use it for both bands and it works fine.  Sorry I don't have a better picture.

Steve Stearns
O235 Longeze 
Boulder / Longmont CO

On Mon, Jun 22, 2020 at 10:39 AM Richard Sessions <rtsessions@...> wrote:
Campers,

I know there has been a lot of discussion on the ADSB-In antenna placements a few months back, but curious to see what people are getting good results with in
a Classic Cozy 3 now that there has been a little more time and likely more experience.

I know there was the slot antenna and others, but I am thinking a 13"ish square foil for the dipole under the left thigh support.  I know it is a projection and subject to ridicule, but pretty simple and not a lot of changes / structure in the back seat area.

I am hooking up to a Dynon HDX system in a panel upgrade and it is about the last thing I have when my newly repaired ADAHRs gets back (static port failure....).

Feel free to contact me off line as I am sure most feel we have done this to death.

Thanks!
Richard
Richard Sessions, Cozy 3 N9455 (William Chorley builder if anyone has anything on it)
Houston's Ellington Field (KEFD) - Go RAFE!
rtsessions@..., 281-467-2432 (leave a message with all the spam....)

Phillip Johnson
 

Hi Steve 

Aren’t you concerned about transmitting high power so close to your head?

Phillip Johnson 


On Jun 23, 2020, at 8:18 AM, Steve Stearns <steve@...> wrote:


I made a wideband dipole out of brass tubing and mounted it on the back of the headrest (Longeze).  I use it for both bands and it works fine.  Sorry I don't have a better picture.

Steve Stearns
O235 Longeze 
Boulder / Longmont CO

On Mon, Jun 22, 2020 at 10:39 AM Richard Sessions <rtsessions@...> wrote:
Campers,

I know there has been a lot of discussion on the ADSB-In antenna placements a few months back, but curious to see what people are getting good results with in
a Classic Cozy 3 now that there has been a little more time and likely more experience.

I know there was the slot antenna and others, but I am thinking a 13"ish square foil for the dipole under the left thigh support.  I know it is a projection and subject to ridicule, but pretty simple and not a lot of changes / structure in the back seat area.

I am hooking up to a Dynon HDX system in a panel upgrade and it is about the last thing I have when my newly repaired ADAHRs gets back (static port failure....).

Feel free to contact me off line as I am sure most feel we have done this to death.

Thanks!
Richard
Richard Sessions, Cozy 3 N9455 (William Chorley builder if anyone has anything on it)
Houston's Ellington Field (KEFD) - Go RAFE!
rtsessions@..., 281-467-2432 (leave a message with all the spam....)

Attachments:

Phillip Johnson
 

Delete my last message, you are only talking about ADSB IN not OUT.

Phillip Johnson 


On Jun 23, 2020, at 8:35 AM, Phillip Johnson via groups.io <Cozy.cgple@...> wrote:

Hi Steve 

Aren’t you concerned about transmitting high power so close to your head?

Phillip Johnson 


On Jun 23, 2020, at 8:18 AM, Steve Stearns <steve@...> wrote:


I made a wideband dipole out of brass tubing and mounted it on the back of the headrest (Longeze).  I use it for both bands and it works fine.  Sorry I don't have a better picture.

Steve Stearns
O235 Longeze 
Boulder / Longmont CO

On Mon, Jun 22, 2020 at 10:39 AM Richard Sessions <rtsessions@...> wrote:
Campers,

I know there has been a lot of discussion on the ADSB-In antenna placements a few months back, but curious to see what people are getting good results with in
a Classic Cozy 3 now that there has been a little more time and likely more experience.

I know there was the slot antenna and others, but I am thinking a 13"ish square foil for the dipole under the left thigh support.  I know it is a projection and subject to ridicule, but pretty simple and not a lot of changes / structure in the back seat area.

I am hooking up to a Dynon HDX system in a panel upgrade and it is about the last thing I have when my newly repaired ADAHRs gets back (static port failure....).

Feel free to contact me off line as I am sure most feel we have done this to death.

Thanks!
Richard
Richard Sessions, Cozy 3 N9455 (William Chorley builder if anyone has anything on it)
Houston's Ellington Field (KEFD) - Go RAFE!
rtsessions@..., 281-467-2432 (leave a message with all the spam....)

Attachments:

Wm Kezele
 

I placed my dipole in the backseat leg area, and used a Nickel based paint to create my ground plane. I don’t have the name of the paint handy but I can get pictures and send more data if you have interest it worked perfect.


On Jun 23, 2020, at 6:36 AM, Phillip Johnson <Cozy.cgple@...> wrote:

Delete my last message, you are only talking about ADSB IN not OUT.

Phillip Johnson 


On Jun 23, 2020, at 8:35 AM, Phillip Johnson via groups.io <Cozy.cgple@...> wrote:

Hi Steve 

Aren’t you concerned about transmitting high power so close to your head?

Phillip Johnson 


On Jun 23, 2020, at 8:18 AM, Steve Stearns <steve@...> wrote:


I made a wideband dipole out of brass tubing and mounted it on the back of the headrest (Longeze).  I use it for both bands and it works fine.  Sorry I don't have a better picture.

Steve Stearns
O235 Longeze 
Boulder / Longmont CO

On Mon, Jun 22, 2020 at 10:39 AM Richard Sessions <rtsessions@...> wrote:
Campers,

I know there has been a lot of discussion on the ADSB-In antenna placements a few months back, but curious to see what people are getting good results with in
a Classic Cozy 3 now that there has been a little more time and likely more experience.

I know there was the slot antenna and others, but I am thinking a 13"ish square foil for the dipole under the left thigh support.  I know it is a projection and subject to ridicule, but pretty simple and not a lot of changes / structure in the back seat area.

I am hooking up to a Dynon HDX system in a panel upgrade and it is about the last thing I have when my newly repaired ADAHRs gets back (static port failure....).

Feel free to contact me off line as I am sure most feel we have done this to death.

Thanks!
Richard
Richard Sessions, Cozy 3 N9455 (William Chorley builder if anyone has anything on it)
Houston's Ellington Field (KEFD) - Go RAFE!
rtsessions@..., 281-467-2432 (leave a message with all the spam....)

Attachments:

Marlon Gunderson
 

Virtual ground plane in the strake cavity has worked well for me for an Echo UAT. Good separation from the Mode C antenna under the front seat.
-Marlon  Cozy3  N129GR

berkut13
 

It may indeed “work”, but the radiation pattern is going to be significantly affected by the asymmetrical ground plane radials.  Could cause some reception issues by ground stations in certain directions. No way to really know without extensive testing.

 

-James

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Marlon Gunderson
Sent: Tuesday, June 23, 2020 3:26 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Virtual ground plane in the strake cavity has worked well for me for an Echo UAT. Good separation from the Mode C antenna under the front seat.

-Marlon  Cozy3  N129GR

Attachments:

Marlon Gunderson
 

Thanks James, you're right, this is totally experimental and may not work reliably for someone else. I have not done any kind of formal testing, just flown with it for 3 years and checked the FAA ADSB performance test a couple of times a year.  It hasn't shown anything other than 0% failures (of about 10K pings/hr) when I've checked but there's nothing to say I won't see some failures in the future. You're less likely to go wrong sticking with a more conventional solution.
-Marlon


On Tue, Jun 23, 2020 at 6:36 PM berkut13 <berkut13@...> wrote:

It may indeed “work”, but the radiation pattern is going to be significantly affected by the asymmetrical ground plane radials.  Could cause some reception issues by ground stations in certain directions. No way to really know without extensive testing.

 

-James

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Marlon Gunderson
Sent: Tuesday, June 23, 2020 3:26 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Virtual ground plane in the strake cavity has worked well for me for an Echo UAT. Good separation from the Mode C antenna under the front seat.

-Marlon  Cozy3  N129GR

Attachments:

Steve Stearns
 

"You're less likely to go wrong sticking with a more conventional solution"

It looks like you have enough room for a dipole antenna (see my previous picture) if you ever decide to upgrade.  It will at least give you better coverage for the volume on the other side of the virtual ground plane and should be more cylindrically symmetric.

Steve Stearns
O235 Longeze
Boulder / Longmont CO

On Tue, Jun 23, 2020 at 9:04 PM Marlon Gunderson <sondergun@...> wrote:
Thanks James, you're right, this is totally experimental and may not work reliably for someone else. I have not done any kind of formal testing, just flown with it for 3 years and checked the FAA ADSB performance test a couple of times a year.  It hasn't shown anything other than 0% failures (of about 10K pings/hr) when I've checked but there's nothing to say I won't see some failures in the future. You're less likely to go wrong sticking with a more conventional solution.
-Marlon

On Tue, Jun 23, 2020 at 6:36 PM berkut13 <berkut13@...> wrote:

It may indeed “work”, but the radiation pattern is going to be significantly affected by the asymmetrical ground plane radials.  Could cause some reception issues by ground stations in certain directions. No way to really know without extensive testing.

 

-James

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Marlon Gunderson
Sent: Tuesday, June 23, 2020 3:26 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Virtual ground plane in the strake cavity has worked well for me for an Echo UAT. Good separation from the Mode C antenna under the front seat.

-Marlon  Cozy3  N129GR

Attachments:

Steve Stearns
 

P.S. Note that the measurements shown in my picture are for a wide-band (to cover both bands) receive only antenna whereas an antenna for transmit/receive on the 900 MHz band should be a little shorter.  (i.e. twice the length of your monopole antenna)

Steve Stearns
O235 Longeze
Boulder / Longmont CO


On Wed, Jun 24, 2020 at 7:52 AM Steve Stearns <steve@...> wrote:
"You're less likely to go wrong sticking with a more conventional solution"

It looks like you have enough room for a dipole antenna (see my previous picture) if you ever decide to upgrade.  It will at least give you better coverage for the volume on the other side of the virtual ground plane and should be more cylindrically symmetric.

Steve Stearns
O235 Longeze
Boulder / Longmont CO

On Tue, Jun 23, 2020 at 9:04 PM Marlon Gunderson <sondergun@...> wrote:
Thanks James, you're right, this is totally experimental and may not work reliably for someone else. I have not done any kind of formal testing, just flown with it for 3 years and checked the FAA ADSB performance test a couple of times a year.  It hasn't shown anything other than 0% failures (of about 10K pings/hr) when I've checked but there's nothing to say I won't see some failures in the future. You're less likely to go wrong sticking with a more conventional solution.
-Marlon

On Tue, Jun 23, 2020 at 6:36 PM berkut13 <berkut13@...> wrote:

It may indeed “work”, but the radiation pattern is going to be significantly affected by the asymmetrical ground plane radials.  Could cause some reception issues by ground stations in certain directions. No way to really know without extensive testing.

 

-James

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Marlon Gunderson
Sent: Tuesday, June 23, 2020 3:26 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Virtual ground plane in the strake cavity has worked well for me for an Echo UAT. Good separation from the Mode C antenna under the front seat.

-Marlon  Cozy3  N129GR

Attachments:

Del Schier
 

I agree those ground plane wires may not work well.  Any piece of wire will “work”, so would a wet noodle LOL.  A half wave antenna is easier to make and would work predictably if you can find a nice place to put it.

 

I have two ADS-B receivers in my Cozy, one inside my ADS-B transponder and the other a dual band homemade Stratux.  I have a printed circuit board J pole antenna made by the transponder mfg in the back upper side of the Cozy for that receiver.  The Stratux has two home made J pole antennas in the nose, one for each band.  See attached.

 

The J pole (see Wikipedia): is very easy and cheap to make and has a good omnidirectional pattern with about 2 dB gain over a dipole or ¼ wave with ground plane. Here is a page to calculate the dimensions: J Pole Calculator

 

With my antenna setup the factory made setup does not work as well as the Stratux with the home made antennas but both work most everywhere I fly.

 

From: members@canardzone.groups.io <members@canardzone.groups.io> On Behalf Of berkut13
Sent: Tuesday, June 23, 2020 7:36 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

It may indeed “work”, but the radiation pattern is going to be significantly affected by the asymmetrical ground plane radials.  Could cause some reception issues by ground stations in certain directions. No way to really know without extensive testing.

 

-James

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Marlon Gunderson
Sent: Tuesday, June 23, 2020 3:26 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Virtual ground plane in the strake cavity has worked well for me for an Echo UAT. Good separation from the Mode C antenna under the front seat.

-Marlon  Cozy3  N129GR

Attachments:

Phillip Johnson
 

Steve,

 

With your dipole arrangement, what did you use to decouple the feedline? Did you use ferrites etc.?

 

Regards,

 

Phillip Johnson
Cozy MKIV RG Powered by Subaru IO-200 (SN 0030)

http://www.canardaviation.com/PhillipJohnson

 

 

 

From: members@canardzone.groups.io <members@canardzone.groups.io> On Behalf Of Steve Stearns
Sent: 24 June 2020 10:18
To: members@canardzone.groups.io; sondergun@...
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

P.S. Note that the measurements shown in my picture are for a wide-band (to cover both bands) receive only antenna whereas an antenna for transmit/receive on the 900 MHz band should be a little shorter.  (i.e. twice the length of your monopole antenna)

 

Steve Stearns

O235 Longeze

Boulder / Longmont CO

 

On Wed, Jun 24, 2020 at 7:52 AM Steve Stearns <steve@...> wrote:

"You're less likely to go wrong sticking with a more conventional solution"

 

It looks like you have enough room for a dipole antenna (see my previous picture) if you ever decide to upgrade.  It will at least give you better coverage for the volume on the other side of the virtual ground plane and should be more cylindrically symmetric.

 

Steve Stearns

O235 Longeze

Boulder / Longmont CO

 

On Tue, Jun 23, 2020 at 9:04 PM Marlon Gunderson <sondergun@...> wrote:

Thanks James, you're right, this is totally experimental and may not work reliably for someone else. I have not done any kind of formal testing, just flown with it for 3 years and checked the FAA ADSB performance test a couple of times a year.  It hasn't shown anything other than 0% failures (of about 10K pings/hr) when I've checked but there's nothing to say I won't see some failures in the future. You're less likely to go wrong sticking with a more conventional solution.

-Marlon

 

On Tue, Jun 23, 2020 at 6:36 PM berkut13 <berkut13@...> wrote:

It may indeed “work”, but the radiation pattern is going to be significantly affected by the asymmetrical ground plane radials.  Could cause some reception issues by ground stations in certain directions. No way to really know without extensive testing.

 

-James

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Marlon Gunderson
Sent: Tuesday, June 23, 2020 3:26 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Virtual ground plane in the strake cavity has worked well for me for an Echo UAT. Good separation from the Mode C antenna under the front seat.

-Marlon  Cozy3  N129GR

Attachments:

Steve Stearns
 

"With your dipole arrangement, what did you use to decouple the feedline? Did you use ferrites etc.? "

I didn't use anything.  But then my dipole is receive-only and the feed line is very short and it's going into two paralleled high impedance inputs (two SDR receivers).  I've found that, generally, dipoles, though not 50 ohms at resonance, still provide low enough SWR to not be a problem for transmitters when on 50 unbalanced feedline.   I expect our aircraft environment is also acceptably tolerant of some shield current but I haven't explicitly tested this configuration.  Jim Weir seemed to like-feed through (aka "current") baluns in his stuff, Bob Nuckolls seems to think they usually don't provide much benefit except for lab measurements and, on other projects where I've wanted them, I've designed full up matching baluns rather than used so called "current baluns".

In short, your mileage may vary.  :-)  If I went this route for transmit on 900 MHz, I'd check the SWR.  I've got parallel dipoles (again, no balun) fed with 50 ohm coax for my ELT antenna (406MHz and 121.5MHz) and its SWR is lower  on both frequencies than the supplied antennas (both the monopole and the "rubber ducky" portable).

Steve Stearns
O235 Longeze
Boulder / Longmont CO

On Wed, Jun 24, 2020 at 12:57 PM Phillip Johnson <phillip.johnson@...> wrote:

Steve,

 

With your dipole arrangement, what did you use to decouple the feedline? Did you use ferrites etc.?

 

Regards,

 

Phillip Johnson
Cozy MKIV RG Powered by Subaru IO-200 (SN 0030)

http://www.canardaviation.com/PhillipJohnson

 

 

 

From: members@canardzone.groups.io <members@canardzone.groups.io> On Behalf Of Steve Stearns
Sent: 24 June 2020 10:18
To: members@canardzone.groups.io; sondergun@...
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

P.S. Note that the measurements shown in my picture are for a wide-band (to cover both bands) receive only antenna whereas an antenna for transmit/receive on the 900 MHz band should be a little shorter.  (i.e. twice the length of your monopole antenna)

 

Steve Stearns

O235 Longeze

Boulder / Longmont CO

 

On Wed, Jun 24, 2020 at 7:52 AM Steve Stearns <steve@...> wrote:

"You're less likely to go wrong sticking with a more conventional solution"

 

It looks like you have enough room for a dipole antenna (see my previous picture) if you ever decide to upgrade.  It will at least give you better coverage for the volume on the other side of the virtual ground plane and should be more cylindrically symmetric.

 

Steve Stearns

O235 Longeze

Boulder / Longmont CO

 

On Tue, Jun 23, 2020 at 9:04 PM Marlon Gunderson <sondergun@...> wrote:

Thanks James, you're right, this is totally experimental and may not work reliably for someone else. I have not done any kind of formal testing, just flown with it for 3 years and checked the FAA ADSB performance test a couple of times a year.  It hasn't shown anything other than 0% failures (of about 10K pings/hr) when I've checked but there's nothing to say I won't see some failures in the future. You're less likely to go wrong sticking with a more conventional solution.

-Marlon

 

On Tue, Jun 23, 2020 at 6:36 PM berkut13 <berkut13@...> wrote:

It may indeed “work”, but the radiation pattern is going to be significantly affected by the asymmetrical ground plane radials.  Could cause some reception issues by ground stations in certain directions. No way to really know without extensive testing.

 

-James

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Marlon Gunderson
Sent: Tuesday, June 23, 2020 3:26 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Virtual ground plane in the strake cavity has worked well for me for an Echo UAT. Good separation from the Mode C antenna under the front seat.

-Marlon  Cozy3  N129GR

Attachments:

Del Schier
 

Steve I would not know how to use ferrite at those frequencies.  A coax balun is easy to make especially if you use 1/8” UT141 semi-rigid coax which solders nicely. See attached.

 

You can make a folded dipole with a 4:1 balun or a simple dipole with a 1:1 balun.  Either way it would work well.  Either way you are making a 75 ohm antenna which would have a slight mismatch with our 50 ohm systems.

 

Del Schier

Cozy IV N197DL

Cannon Creek Airpark 15FL

 

 

From: members@canardzone.groups.io <members@canardzone.groups.io> On Behalf Of Steve Stearns
Sent: Wednesday, June 24, 2020 3:36 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

"With your dipole arrangement, what did you use to decouple the feedline? Did you use ferrites etc.? "

 

I didn't use anything.  But then my dipole is receive-only and the feed line is very short and it's going into two paralleled high impedance inputs (two SDR receivers).  I've found that, generally, dipoles, though not 50 ohms at resonance, still provide low enough SWR to not be a problem for transmitters when on 50 unbalanced feedline.   I expect our aircraft environment is also acceptably tolerant of some shield current but I haven't explicitly tested this configuration.  Jim Weir seemed to like-feed through (aka "current") baluns in his stuff, Bob Nuckolls seems to think they usually don't provide much benefit except for lab measurements and, on other projects where I've wanted them, I've designed full up matching baluns rather than used so called "current baluns".

In short, your mileage may vary.  :-)  If I went this route for transmit on 900 MHz, I'd check the SWR.  I've got parallel dipoles (again, no balun) fed with 50 ohm coax for my ELT antenna (406MHz and 121.5MHz) and its SWR is lower  on both frequencies than the supplied antennas (both the monopole and the "rubber ducky" portable).

 

Steve Stearns

O235 Longeze

Boulder / Longmont CO

 

On Wed, Jun 24, 2020 at 12:57 PM Phillip Johnson <phillip.johnson@...> wrote:

Steve,

 

With your dipole arrangement, what did you use to decouple the feedline? Did you use ferrites etc.?

 

Regards,

 

Phillip Johnson
Cozy MKIV RG Powered by Subaru IO-200 (SN 0030)

http://www.canardaviation.com/PhillipJohnson

 

 

 

From: members@canardzone.groups.io <members@canardzone.groups.io> On Behalf Of Steve Stearns
Sent: 24 June 2020 10:18
To: members@canardzone.groups.io; sondergun@...
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

P.S. Note that the measurements shown in my picture are for a wide-band (to cover both bands) receive only antenna whereas an antenna for transmit/receive on the 900 MHz band should be a little shorter.  (i.e. twice the length of your monopole antenna)

 

Steve Stearns

O235 Longeze

Boulder / Longmont CO

 

On Wed, Jun 24, 2020 at 7:52 AM Steve Stearns <steve@...> wrote:

"You're less likely to go wrong sticking with a more conventional solution"

 

It looks like you have enough room for a dipole antenna (see my previous picture) if you ever decide to upgrade.  It will at least give you better coverage for the volume on the other side of the virtual ground plane and should be more cylindrically symmetric.

 

Steve Stearns

O235 Longeze

Boulder / Longmont CO

 

On Tue, Jun 23, 2020 at 9:04 PM Marlon Gunderson <sondergun@...> wrote:

Thanks James, you're right, this is totally experimental and may not work reliably for someone else. I have not done any kind of formal testing, just flown with it for 3 years and checked the FAA ADSB performance test a couple of times a year.  It hasn't shown anything other than 0% failures (of about 10K pings/hr) when I've checked but there's nothing to say I won't see some failures in the future. You're less likely to go wrong sticking with a more conventional solution.

-Marlon

 

On Tue, Jun 23, 2020 at 6:36 PM berkut13 <berkut13@...> wrote:

It may indeed “work”, but the radiation pattern is going to be significantly affected by the asymmetrical ground plane radials.  Could cause some reception issues by ground stations in certain directions. No way to really know without extensive testing.

 

-James

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Marlon Gunderson
Sent: Tuesday, June 23, 2020 3:26 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Virtual ground plane in the strake cavity has worked well for me for an Echo UAT. Good separation from the Mode C antenna under the front seat.

-Marlon  Cozy3  N129GR

Attachments: