Date   

Re: iPad WiFi only or cellular

aviationeyes
 

I've recently been using my old original iPad-mini in my long-ez. It is a wifi only version running iFly-GPS. It readily picks up the GPS signal from my uavionics based ADSB in/out system. I get maps, position, traffic, weather, although there have been rare instances of the iPad or iFly not acquiring the GPS. (It's a bug I have to figure out)   Overall it has been very satisfactory, although I find even the mini iPad kinda big in the Long-EZ cockpit (it is ram mounted to the longeron). Btw, I recently compared it to he latest mini and I wasn't impressed by how much better (brightness and contrast) the newer screen display was. 
--Jose


On Sat, Jul 18, 2020, at 3:40 AM, JOHN STEICHEN wrote:
Absolutely Neil. I had forgotten the gps aspect. Very important distinction John s

On Fri, Jul 17, 2020 at 10:12 AM Neil K <neil.kruiswyk@...> wrote:
If you have an alternate gps source like Stratus or Stratux then wifi only works fine (although the cell model has gps which makes a good backup)

Neil K.


On Jul 17, 2020, at 10:36 AM, JOHN STEICHEN <nn27gz@...> wrote:

I have, in the past always purchased iPads with cellular. I continue to do so with my traveling ( ergo aviation ) iPad same with my wife’s mini iPad. We only do mini iPads. We have no professional use for the iPads. 
I just replaced my wife’s mini iPad for what looked like a hardware failure of the wifi component. since we dont travel as much and wifi is more available, I opted not to add the cellular component to her new mini ipad. 
for me,  the full size ipad is too large for my aviation uses.   In my cockpit I have 2 ipads.  One is nothing but a approach plate backup as I carry no paper plates or maps anymore. It is cheaper to buy a bottom of the line ipad for your backup than to maintain ANY current paper products. No that my 
Dynon has the seattle avionics maping and plates, the extra belt and suspenders extra ipad probablly over kill.  BTW  the extra backup ipad has always been wifi. 
although my phone has foreflight on it, i dont tend to use it for aviation very much, but probably could substitute for the cellular connection that you need for filing flight plans away from home.  Also  the asdb weather might substitute for a cellular connection  for pre takeoff weather from my ipad.  Do I have you confused?  LOL

On Fri, Jul 17, 2020 at 8:21 AM Spencer Boesch via groups.io <spencersouthbend=yahoo.com@groups.io> wrote:
Good morning all,
Looking at upgrading and just asking for current thoughts or experiences.
Thanks in advance!






-- 
  



Re: iPad WiFi only or cellular

JOHN STEICHEN
 

Absolutely Neil. I had forgotten the gps aspect. Very important distinction John s

On Fri, Jul 17, 2020 at 10:12 AM Neil K <neil.kruiswyk@...> wrote:
If you have an alternate gps source like Stratus or Stratux then wifi only works fine (although the cell model has gps which makes a good backup)

Neil K.

On Jul 17, 2020, at 10:36 AM, JOHN STEICHEN <nn27gz@...> wrote:


I have, in the past always purchased iPads with cellular. I continue to do so with my traveling ( ergo aviation ) iPad same with my wife’s mini iPad. We only do mini iPads. We have no professional use for the iPads. 
I just replaced my wife’s mini iPad for what looked like a hardware failure of the wifi component. since we dont travel as much and wifi is more available, I opted not to add the cellular component to her new mini ipad. 
for me,  the full size ipad is too large for my aviation uses.   In my cockpit I have 2 ipads.  One is nothing but a approach plate backup as I carry no paper plates or maps anymore. It is cheaper to buy a bottom of the line ipad for your backup than to maintain ANY current paper products. No that my 
Dynon has the seattle avionics maping and plates, the extra belt and suspenders extra ipad probablly over kill.  BTW  the extra backup ipad has always been wifi. 
although my phone has foreflight on it, i dont tend to use it for aviation very much, but probably could substitute for the cellular connection that you need for filing flight plans away from home.  Also  the asdb weather might substitute for a cellular connection  for pre takeoff weather from my ipad.  Do I have you confused?  LOL

On Fri, Jul 17, 2020 at 8:21 AM Spencer Boesch via groups.io <spencersouthbend=yahoo.com@groups.io> wrote:
Good morning all,
Looking at upgrading and just asking for current thoughts or experiences.
Thanks in advance!


Re: iPad WiFi only or cellular

Jim Evans
 

I don't think I would tell anyone that you were flying with a Maxipad!!


On Fri, Jul 17, 2020, 20:13 Vernon Asper <vernon.asper@...> wrote:
FWIW, I haven’t extra large version that I call the Maxi Pad.  I like the larger size and haven’t had any problems with it getting in the way.  No cell connection; just WiFi to me ADSB.

Vernon

On Jul 17, 2020, at 10:36 AM, JOHN STEICHEN <nn27gz@...> wrote:


I have, in the past always purchased iPads with cellular. I continue to do so with my traveling ( ergo aviation ) iPad same with my wife’s mini iPad. We only do mini iPads. We have no professional use for the iPads. 
I just replaced my wife’s mini iPad for what looked like a hardware failure of the wifi component. since we dont travel as much and wifi is more available, I opted not to add the cellular component to her new mini ipad. 
for me,  the full size ipad is too large for my aviation uses.   In my cockpit I have 2 ipads.  One is nothing but a approach plate backup as I carry no paper plates or maps anymore. It is cheaper to buy a bottom of the line ipad for your backup than to maintain ANY current paper products. No that my 
Dynon has the seattle avionics maping and plates, the extra belt and suspenders extra ipad probablly over kill.  BTW  the extra backup ipad has always been wifi. 
although my phone has foreflight on it, i dont tend to use it for aviation very much, but probably could substitute for the cellular connection that you need for filing flight plans away from home.  Also  the asdb weather might substitute for a cellular connection  for pre takeoff weather from my ipad.  Do I have you confused?  LOL

On Fri, Jul 17, 2020 at 8:21 AM Spencer Boesch via groups.io <spencersouthbend=yahoo.com@groups.io> wrote:
Good morning all,
Looking at upgrading and just asking for current thoughts or experiences.
Thanks in advance!


Re: iPad WiFi only or cellular

Vernon Asper
 

FWIW, I haven’t extra large version that I call the Maxi Pad.  I like the larger size and haven’t had any problems with it getting in the way.  No cell connection; just WiFi to me ADSB.

Vernon

On Jul 17, 2020, at 10:36 AM, JOHN STEICHEN <nn27gz@...> wrote:


I have, in the past always purchased iPads with cellular. I continue to do so with my traveling ( ergo aviation ) iPad same with my wife’s mini iPad. We only do mini iPads. We have no professional use for the iPads. 
I just replaced my wife’s mini iPad for what looked like a hardware failure of the wifi component. since we dont travel as much and wifi is more available, I opted not to add the cellular component to her new mini ipad. 
for me,  the full size ipad is too large for my aviation uses.   In my cockpit I have 2 ipads.  One is nothing but a approach plate backup as I carry no paper plates or maps anymore. It is cheaper to buy a bottom of the line ipad for your backup than to maintain ANY current paper products. No that my 
Dynon has the seattle avionics maping and plates, the extra belt and suspenders extra ipad probablly over kill.  BTW  the extra backup ipad has always been wifi. 
although my phone has foreflight on it, i dont tend to use it for aviation very much, but probably could substitute for the cellular connection that you need for filing flight plans away from home.  Also  the asdb weather might substitute for a cellular connection  for pre takeoff weather from my ipad.  Do I have you confused?  LOL

On Fri, Jul 17, 2020 at 8:21 AM Spencer Boesch via groups.io <spencersouthbend=yahoo.com@groups.io> wrote:
Good morning all,
Looking at upgrading and just asking for current thoughts or experiences.
Thanks in advance!


Re: iPad WiFi only or cellular

Neil K
 

If you have an alternate gps source like Stratus or Stratux then wifi only works fine (although the cell model has gps which makes a good backup)

Neil K.

On Jul 17, 2020, at 10:36 AM, JOHN STEICHEN <nn27gz@...> wrote:


I have, in the past always purchased iPads with cellular. I continue to do so with my traveling ( ergo aviation ) iPad same with my wife’s mini iPad. We only do mini iPads. We have no professional use for the iPads. 
I just replaced my wife’s mini iPad for what looked like a hardware failure of the wifi component. since we dont travel as much and wifi is more available, I opted not to add the cellular component to her new mini ipad. 
for me,  the full size ipad is too large for my aviation uses.   In my cockpit I have 2 ipads.  One is nothing but a approach plate backup as I carry no paper plates or maps anymore. It is cheaper to buy a bottom of the line ipad for your backup than to maintain ANY current paper products. No that my 
Dynon has the seattle avionics maping and plates, the extra belt and suspenders extra ipad probablly over kill.  BTW  the extra backup ipad has always been wifi. 
although my phone has foreflight on it, i dont tend to use it for aviation very much, but probably could substitute for the cellular connection that you need for filing flight plans away from home.  Also  the asdb weather might substitute for a cellular connection  for pre takeoff weather from my ipad.  Do I have you confused?  LOL

On Fri, Jul 17, 2020 at 8:21 AM Spencer Boesch via groups.io <spencersouthbend=yahoo.com@groups.io> wrote:
Good morning all,
Looking at upgrading and just asking for current thoughts or experiences.
Thanks in advance!


Re: iPad WiFi only or cellular

JOHN STEICHEN
 

I have, in the past always purchased iPads with cellular. I continue to do so with my traveling ( ergo aviation ) iPad same with my wife’s mini iPad. We only do mini iPads. We have no professional use for the iPads. 
I just replaced my wife’s mini iPad for what looked like a hardware failure of the wifi component. since we dont travel as much and wifi is more available, I opted not to add the cellular component to her new mini ipad. 
for me,  the full size ipad is too large for my aviation uses.   In my cockpit I have 2 ipads.  One is nothing but a approach plate backup as I carry no paper plates or maps anymore. It is cheaper to buy a bottom of the line ipad for your backup than to maintain ANY current paper products. No that my 
Dynon has the seattle avionics maping and plates, the extra belt and suspenders extra ipad probablly over kill.  BTW  the extra backup ipad has always been wifi. 
although my phone has foreflight on it, i dont tend to use it for aviation very much, but probably could substitute for the cellular connection that you need for filing flight plans away from home.  Also  the asdb weather might substitute for a cellular connection  for pre takeoff weather from my ipad.  Do I have you confused?  LOL

On Fri, Jul 17, 2020 at 8:21 AM Spencer Boesch via groups.io <spencersouthbend=yahoo.com@groups.io> wrote:
Good morning all,
Looking at upgrading and just asking for current thoughts or experiences.
Thanks in advance!


iPad WiFi only or cellular

Spencer Boesch
 

Good morning all,
Looking at upgrading and just asking for current thoughts or experiences.
Thanks in advance!


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

Jim Weir
 

I don’t use them for baluns. (BALanced to Unbalanced)     The ONLY reason I use them is to strip the always-present RF being reflected down the outside of the shield from getting into the rest of the electronics by radiation.  There is nothing inherently wrong with a dipole connected one ear to center conductor and one ear to the shield with (as I said above) RF being reflected down the outside of the shield.

 

Jim

 

From: members@canardzone.groups.io [mailto:members@canardzone.groups.io] On Behalf Of Steve Stearns
Sent: Wednesday, June 24, 2020 12:36 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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

Phillip Johnson
 

I was more concerned about the feedline impacting the beampattern rather than the impedance.

 

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 15:36
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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

Steve Stearns
 

Del, 

Did you it's two j-poles or use one for both SDRs?

Steve.


On Wed, Jun 24, 2020, 6:09 PM Del Schier <cozypilot@...> wrote:

Your right Steve, I was not commenting on what you posted but to whomever asked: "With your dipole arrangement, what did you use to decouple the feedline? Did you use ferrites etc.? "

For ADS-B in (receive) I don’t think it matters much what you use for antennas as long as they are made out of metal and not mounted with metal nearby, or blocking the signal.

 

When I first put in the Stratux I was using the magnetic mount telescoping whips that came with the USB sticks.  I had them set to ~ ¼ wave long and set on top of my COM radio tray near the top of the panel.  I had to use double sided tape as magnets don’t stick to aluminum.

 

I didn’t get ADS-B “Towers” everywhere so I mad the J poles for up in the nose.  On a flight in an area where I got no signal the J pole antennas got 6 Towers at the same altitude so I stuck with that.  The J poles are easy, cheap, light, have gain, 50 ohm and don’t need baluns, not that you need baluns.  What I didn’t do is tune them for 978 and 1090 as I couldn’t figure out which USB rcvr was on which band with the Stratux.  I just cut them for about ½ way in between.

 

With my ADS-B transponder I did make the annular slot antenna tuned and tested for SWR at 978. That was a huge project compared to the receiver setup.

 

Del Schier,

Ham Radio: K1UHF

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 5:20 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Hi Del,

 

I think you meant to address that to Phillip.  I believe you and I are are on the same page with the possible exception that I am lazier than you and wouldn't bother with any balun unless I believed I would notice the difference.

 

Steve Stearns AB0KB

O235 Longeze

Boulder / Longmont CO

 

On Wed, Jun 24, 2020, 3:06 PM Del Schier <cozypilot@...> wrote:

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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

Del Schier
 

Your right Steve, I was not commenting on what you posted but to whomever asked: "With your dipole arrangement, what did you use to decouple the feedline? Did you use ferrites etc.? "

For ADS-B in (receive) I don’t think it matters much what you use for antennas as long as they are made out of metal and not mounted with metal nearby, or blocking the signal.

 

When I first put in the Stratux I was using the magnetic mount telescoping whips that came with the USB sticks.  I had them set to ~ ¼ wave long and set on top of my COM radio tray near the top of the panel.  I had to use double sided tape as magnets don’t stick to aluminum.

 

I didn’t get ADS-B “Towers” everywhere so I mad the J poles for up in the nose.  On a flight in an area where I got no signal the J pole antennas got 6 Towers at the same altitude so I stuck with that.  The J poles are easy, cheap, light, have gain, 50 ohm and don’t need baluns, not that you need baluns.  What I didn’t do is tune them for 978 and 1090 as I couldn’t figure out which USB rcvr was on which band with the Stratux.  I just cut them for about ½ way in between.

 

With my ADS-B transponder I did make the annular slot antenna tuned and tested for SWR at 978. That was a huge project compared to the receiver setup.

 

Del Schier,

Ham Radio: K1UHF

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 5:20 PM
To: members@canardzone.groups.io
Subject: Re: [Canard Zone] ADSB In - Classic Cozy 3 Antenna Placement Experience

 

Hi Del,

 

I think you meant to address that to Phillip.  I believe you and I are are on the same page with the possible exception that I am lazier than you and wouldn't bother with any balun unless I believed I would notice the difference.

 

Steve Stearns AB0KB

O235 Longeze

Boulder / Longmont CO

 

On Wed, Jun 24, 2020, 3:06 PM Del Schier <cozypilot@...> wrote:

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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

Steve Stearns
 

Hi Del,

I think you meant to address that to Phillip.  I believe you and I are are on the same page with the possible exception that I am lazier than you and wouldn't bother with any balun unless I believed I would notice the difference.

Steve Stearns AB0KB
O235 Longeze
Boulder / Longmont CO


On Wed, Jun 24, 2020, 3:06 PM Del Schier <cozypilot@...> wrote:

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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

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:


Re: ADSB In - Classic Cozy 3 Antenna Placement Experience

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: