Quick Login

Author Topic: Help Discerning Which Antenna(s) To Install  (Read 705 times)

Offline VA4SR

  • Petty Officer
  • *
  • Posts: 10
  • Country: ca
Help Discerning Which Antenna(s) To Install
« on: February 21, 2018, 09:59:19 UTC »
Some experiences have lasting impact.

When I was new to ham radio I listened to an operator out of Panama who was operating QRP (in milliwatts) using an eleven element 20 metre beam.  His signal strength registered 20+ dBs!  That was a great lesson for me; the antenna was more important than the power.

Thirty-one years later I now live on a farm and have collected enough towers and treated poles to install some fine wire antennas.

I hope to get a rhombic up and pointed 30 degrees east of north so that I can work Europe QRP regularly.

I have scrounged an 88' free standing commercial tower, several 30' tv towers, four 40' pressure treated posts, and several 30' older telephone poles.

My question for you is: As QRP ops what wire antennas would you install?  I'd really like to hear what you have to say...

73

Craig
VA4SR

Offline GM0LVI

  • Admiral
  • *
  • Posts: 393
  • Country: scotland
Re: Help Discerning Which Antenna(s) To Install
« Reply #1 on: February 21, 2018, 18:17:07 UTC »
I envy you the space you have! I'm limited in space and would never be permitted a taller mast than the 30' one I have installed.
As far as antennas go, I think a quad is just about perfect for QRP as it is much quieter than a yagi and thus better for detecting weak signals. For the lower bands a steerable Vee beam works pretty well, I used one on an IOTA contest expedition. At home I've used a pair of 1/4 wave verticals with phase shift to give directional gain on 80m - worked pretty well though being verticals it was a noisy antenna.
With the number of tall poles/towers you have you could think about delta loops, either single or multi element, with the loops suspended from a catenary running between your poles.
Dave

Offline VA4SR

  • Petty Officer
  • *
  • Posts: 10
  • Country: ca
Re: Help Discerning Which Antenna(s) To Install
« Reply #2 on: February 22, 2018, 13:27:42 UTC »
GM Dave!

Thank you for your recommendations.  I am just now starting to work through the possibilities and will look up each of your suggestions.

I was hoping to get away from any rotational antennas.  I'd sooner put up several sloping V's from the 88' tower with a way to switch between them physically at the tower base, but I will nevertheless keep a quad in mind.  It is an exceptionally windy location at which we live.

If you have any future thoughts be sure to register those as well!


Offline GM0LVI

  • Admiral
  • *
  • Posts: 393
  • Country: scotland
Re: Help Discerning Which Antenna(s) To Install
« Reply #3 on: February 22, 2018, 20:46:03 UTC »
You might want to consider remote switching rather than having to go outside to change bands/direction.
I use a Top Ten Devices relay box out in the garden and can switch between up to six antennas that feed into the shack via a single hardline feeder. The Top Ten relay box wasn't cheap but you could easily make your own from co-ax relays. I use some Cat5 cable, doubled up to run between the switch box in the shack out to the relay box in the garden.
One advantage of my system is that any antennas that are not in use are earthed and when there is no power at all to the box all antennas are earthed and my radios are completely and safely  isolated from any antenna.
Dave

Offline VA4SR

  • Petty Officer
  • *
  • Posts: 10
  • Country: ca
Re: Help Discerning Which Antenna(s) To Install
« Reply #4 on: February 24, 2018, 03:30:57 UTC »
Thanks Dave...

...I'd rather not add remote switching...I am an outdoor person so don't mind doing the legwork, even at -30 ;)

...and there's just something about keeping my setup as simple as possible that I find as attractive as low power transmission itself...I've been a ham 30 years and I'll go to my grave still fascinated that I can talk to the world on the same power as a low wattage lightbulb!  More gadgets, more electronics, and more power only have gotten me into more trouble! ;)

I will have to ask at some point about simple antennas as I access remote backcountry here, usually marshy or rocky and in some places with no trees...but that's for another thread

73

Craig
VA4SR

Offline VE2TH

  • Rear Admiral
  • *
  • Posts: 202
  • Country: ca
Re: Help Discerning Which Antenna(s) To Install
« Reply #5 on: March 01, 2018, 19:55:47 UTC »
Hello again Craig,

Well if I had a farm like this, it is sure I would like to install some fixed Wire Beam or fixed wire delta loops in Quad configuration. (TRIANGLE). with the wood poles you have it would be a lot of fun!!!

Two books came to my mind:

From ED M. NOLL, W3FQJ who is now Silent Key.

Book 1: 73 DIPOLE AND LONG WIRE ANTENNAS, 150 PAGES.

Book 2: 73 VERTICAL AND BEAM ANTENNAS, 161 PAGES

In those books only one thing is missing, is How to match these antennas?

Sure it is with some baluns, or antenna tuner, manual or automatic, or antomatic remote, etc..

As you may know, in those books you will find some wire antennas with great gain, but also with some high impedance.

Another set of real good books, well explained, are those from R.L. CEBIK W4RNL, but there are hard to find.

If it can help you those bookd are highly recommended.

See you,

72/73, Michel VE2TH

I love QRP/QRPp & CW

Offline VE2TH

  • Rear Admiral
  • *
  • Posts: 202
  • Country: ca
Re: Help Discerning Which Antenna(s) To Install
« Reply #6 on: March 02, 2018, 00:37:03 UTC »
Good evening Craig,

Concerning the QUAD ANTENNA, I forgot to tell you of 2 "very good & instructive books" plus another Document from TEN-TEN Club.

1- QUAD ANTENNA VOL: 1 CUBICVAL QUAD NOTES, 188 PAGES
A REVIEW OF EXISTING DESIGNS
BY: L,B, CEBIK W4-RNL (SK)
--------------------------------------------------------------------------------
2- CUBICAL QUAD NOTES VOL: 2, 231 PAGES

 RETHINKING THE QUAD BEAM
BY: L.B CEBIK, W4RNL (SK)
------------------------------------------------------------------------------

3- This one come from TEN-TEN CLUB of California,

    Title: AN-TEN-TEN-NAS BY: L.B. CEBIK, W4RNL (SK)Ten-Ten no: 41159,


This 216 pages document contains 58 different articles concerning antennas and related subject
 
about ten meter antennas, very interesting.-


May be I have it here in my .PDF Antennas Document.

72/73 to all,

Michel VE2TH  The QRP'er,   didit...
I love QRP/QRPp & CW

Offline VA4SR

  • Petty Officer
  • *
  • Posts: 10
  • Country: ca
Re: Help Discerning Which Antenna(s) To Install
« Reply #7 on: March 03, 2018, 17:39:49 UTC »
Michel,

I will look all of those up.  And thank you for your time in responding.  As spring approaches I am able to get outside and take some reading on antenna lengths, tower height, obstructions, etc..  There's a lot to work through which for me starts with visualizing.  Thanks also for emailing me the PDF's of the books that you have...

Later!

73

Craig
VA4SR