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Active VOR antenna

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berkut13(at)berkut13.com
Guest

Posted: Fri Apr 24, 2015 12:44 pm Post subject: Active VOR antenna

Bob,

  

 Have you been able to assess the active VOR antenna?   Weâ€™re  about 30 days from first flight and really need a retrofit VOR antenna solution  for this bird as we discussed.

  

 Thanks,

 James

  

  

    

  From: Robert L. Nuckolls, III (nuckolls.bob(at)aeroelectric.com) 

 Sent: Wednesday, December 03, 2014 11:14 AM

 To: aeroelectric-list(at)matronics.com (aeroelectric-list(at)matronics.com)  

 Subject: Toroid beads VOR antenna vs. Active VOR  antenna

  



 

[img]cid:22E5D2A251FF411890F9053FEEDC3653(at)DEFIANT2600[/img]



  

  I may mount one of this things on my roof  and

  see how it compares with monitor antennas I

  have for  listening to local city, police and

  fire services.



  I  have one HF active antenna up there already.

  

http://tinyurl.com/ou2ezdy



  The 'antenna' part  of this critter is only a

  few inches long. I don't have any other  HF

  optimized antennas up yet to compare it to . . .

  but this  'lump' on the end of a piece of coax

  hears 'lots of stuff'. Given that  the 'stuff'

  of which VOR is made (high power, line of sight)

   it seems that our little experiment has a high

  probability of success  for replacing the legacy

  dipoles and whiskers so favored by our  TC

  brothers.

  



 

  Bob . . .

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nuckolls.bob(at)aeroelect
Guest

Posted: Fri Apr 24, 2015 12:57 pm Post subject: Active VOR antenna

At 15:43 2015-04-24, you wrote:

 	  Quote: 	
		  Bob,



Have you been able to assess the active VOR 

antenna?   Weâ€™re about 30 days from first 

flight and really need a retrofit VOR antenna 

solution for this bird as we discussed.



Thanks,

James


	


  It's in the que. I've got some boards to order

  for another project next week, this board can

  piggyback onto the 'scrap end' . . . thanks

  for rattling my cage.  All the parts are on hand.



   Bob . . .

ronmarks(at)gmail.com
Guest

Posted: Sat Apr 25, 2015 12:07 am Post subject: Active VOR antenna

Bob,

 Hope springs eternal....Â Â A wideband RF amp such as  this on a tiny antenna, while it may be OK, even greatÂ for a rooftop monitor, is  not going to be a satisfactory substitute for a tuned VHF nav antenna in an  aircraft. Overloading, crosstalk and s/n ratio are some ofÂ its inherent  deficits. It may seem to be good enough testing in the boonies, but  ..

 Try it. Play with it. But don't proceed in a way  that you can't re-do easily.

 Ron

On Fri, Apr 24, 2015 at 1:55 PM, Robert L. Nuckolls, III <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)> wrote:

[quote]--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com (nuckolls.bob(at)aeroelectric.com)>

 

 At 15:43 2015-04-24, you wrote:

  	  Quote: 	
		   Bob,

 

 Have you been able to assess the active VOR antenna?Â  Â Weâ€™re about 30 days from first flight and really need a retrofit VOR antenna solution for this bird as we discussed.

 

 Thanks,

 James

 	
 

 Â It's in the que. I've got some boards to order

 Â for another project next week, this board can

 Â piggyback onto the 'scrap end' . . . thanks

 Â for rattling my cage.Â  All the parts are on hand.

 

 

 

 Â  Bob . . . 

 

 

 ===========

  -

 Electric-List" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List

 ===========

  FORUMS -

 _blank">http://forums.matronics.com

 ===========

 b Site -

 Â  Â  Â  Â  Â  -Matt Dralle, List Admin.

 target="_blank">http://www.matronics.com/contribution

 ===========

 

 

 

 [b]

nuckolls.bob(at)aeroelect
Guest

Posted: Sat Apr 25, 2015 4:38 am Post subject: Active VOR antenna

At 03:06 2015-04-25, you wrote:

  	  Quote: 	
		   Bob,

 Hope springs eternal....Â Â A wideband RF amp such as this on a tiny antenna, while it may be OK, even greatÂ for a rooftop monitor, is not going to be a satisfactory substitute for a tuned VHF nav antenna in an aircraft. Overloading, crosstalk and s/n ratio are some ofÂ its inherent deficits. It may seem to be good enough testing in the boonies, but ..

 Try it. Play with it. But don't proceed in a way that you can't re-do easily.

 Ron 	


    There's no 'hope' about it . . . performance of such

    devices are well known . . . as are their shortcomings.

    Nobody is talking about a free lunch here. The goal

    is to explore an option for getting a VOR antenna

    into a uniquely unfriendly space . . . into a tube

    buried in a leading edge.



    There are no promises or expectations for equivalency

    -OR- resistance to the effects of inter modulation

    distortion. The expectation is that it will offer

    serviceable VOR performance under SOME conditions

    with reservations.



    It's a certainty that shortcomings will have to

    be evaluated by the user. I've not fired up a

    VOR receiver in the last 200-300 hours in the

    log. The active antenna is a minimum effort,

    low cost way to squeeze a bit more utility out

    of a dying technology for this user in one airplane.



    No warranty implied - it's a "caveat emptor" of the

    first order.   

    



 

 

   Bob . . .    [quote][b]

berkut13(at)berkut13.com
Guest

Posted: Sat Apr 25, 2015 9:57 am Post subject: Active VOR antenna

Kewl beans, Bob!  Thanks again for the help.

-James



--

nuckolls.bob(at)aeroelect
Guest

Posted: Thu May 07, 2015 3:38 pm Post subject: Active VOR antenna

At 15:43 2015-04-24, you wrote:

 	  Quote: 	
		  Bob,



Have you been able to assess the active VOR 

antenna?   Weâ€™re about 30 days from first 

flight and really need a retrofit VOR antenna 

solution for this bird as we discussed.


	


   What is the length of cable from the

   end of the antenna to your receiver?



   Bob . . .

berkut13(at)berkut13.com
Guest

Posted: Fri May 08, 2015 10:05 am Post subject: Active VOR antenna

About a 24-30" run between antenna location and Garmin GTN-650 radio.



I would plan a short pigtail ~4" off the end of the antenna with a female 

BNC connector.  Similar with the power wire.  To allow the canard to be 

removed for maintenance and inspection, connectors local to the antenna 

installation area are required.



Thanks,

-James





--

nuckolls.bob(at)aeroelect
Guest

Posted: Fri May 08, 2015 1:08 pm Post subject: Active VOR antenna

At 15:43 2015-04-24, you wrote:

 	  Quote: 	
		  Bob,



Have you been able to assess the active VOR 

antenna?   Weâ€™re about 30 days from first 

flight and really need a retrofit VOR antenna 

solution for this bird as we discussed.



Thanks,

James


	




  What is the coax cable length from cable end of antenna

  to your receiver. Is the receiver connector BNC?



   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Fri May 08, 2015 1:10 pm Post subject: Active VOR antenna

At 13:03 2015-05-08, you wrote:

 	  Quote: 	
		  



About a 24-30" run between antenna location and Garmin GTN-650 radio.



I would plan a short pigtail ~4" off the end of the antenna with a 

female BNC connector.  Similar with the power wire.  To allow the 

canard to be removed for maintenance and inspection, connectors 

local to the antenna installation area are required.



Thanks,

-James


	


   Oops . . . missed this. Will do.



   Bob . . .

highwire

Joined: 29 Apr 2015
Posts: 2

Posted: Sat May 09, 2015 10:36 am Post subject: Re: Active VOR antenna

 	  berkut13(at)berkut13.com wrote: 	
		  About a 24-30" run between antenna location and Garmin GTN-650 radio.



I would plan a short pigtail ~4" off the end of the antenna with a female 

BNC connector.  Similar with the power wire.  To allow the canard to be 

removed for maintenance and inspection, connectors local to the antenna 

installation area are required.



Thanks,

-James



Hi James,



What are the physical sizes of the area that you have to install an antenna?  I am guessing from what has been posted, that it is a tubular space in each canard accessible from the root. Is the canard glass and the nose of carbon? What is the spread between the canard roots?

 I started simulating, modelling and lab testing antennas a few years age for my own plane and my own entertainment.  Your application looks like it may be a challenge for a conventional solution, but who knows.   

Ron

--

berkut13(at)berkut13.com
Guest

Posted: Sat May 09, 2015 11:12 am Post subject: Active VOR antenna

A challenge, for sure.



The concept here is to retrofit an active (amplified), end fed, single 

element antenna into the LE D-section of an existing canard on one side. 

The canard is glass skinned and will be invisible to the antenna. However, 

the center spar caps are carbon and the typical retrofit of adding a foil 

"V" style antenna to the exterior of the bottom skin is not ideal.   A 

"dipole on a stick" was the original idea, but there is no space to get the 

coax away from the elements.



The canard is solid foam core, in which a conduit was drilled out in the LE 

running from the center to one tip.  This will be where the antenna will be 

inserted.  There is a small "access box" (if you can call it that) cut in 

the foam at the center of the canard where the antenna can be accessed, 

however once installed and the skin in patched, it will require cutting the 

fiberglass repair patch off each time.  Sounds worse than it really is and 

is actually less work than installing the external foil elements and trying 

to re-contour the already critical profile of a small airfoil.



Fingers crossed this works!



-James



--

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