• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

puting up antenna

joespunn23

Member
Jul 27, 2010
30
0
16
central new jersey
morning everyone i have a couple questions maybe i can get advice on i have an old aluminum ground plane that i recently just saved from the junk pile . now that it is all cleaned up and ready to use i have some questions on it performace. well ideally it would be great to mount this antenna on the roof which would have put it at a little over 1 wave lenght above ground(27 mhz) . but this is not an option due to renting . but i was told that i could mount it next to the gerage . the antenna will mounted on a 1 1/4 tv mast i have the base about 16 feet above ground which i beleive would put it a little under 1/2 a wavelenght. my 1st question is there is 16 feet of antenna mast which is on the ground do i need instulated this tv mact from the the ground . 2nd ? is how much differance will the angle of radtion be at 1/2 a wave lenght abovr ground compared to to 1 full wavelenght? also will the toa be differant or the same next ? is i have read a couple pages talking about use elevated ground radials compared to useing ground radial on the ground since the base of the antenna is 16 feet above ground but the mast the antenna is mounted to is sitting on the ground im not sure what type of set up to use or could i use both elevated ground radials (4 of them) and about 20 16 foot radials on the ground well thanks everyone and 73s
 

That 1/2 wave above ground versus the full wave above ground will probably make little difference in that AOR or TOA (whatever you want to call it). At least nothing significant much. I wouldn't worry about that TOA, it's usefulness will vary according to propagation anyway.
A groundplane antenna doesn't depend on the mast it's mounted on being grounded or not. That mast grounding is for safety, not RF. By definition, those radials should be located at the bottom of the vertical at the feed point. Otherwise, it really isn't a groundplane antenna, right? Radials at the base of the support mast DO make for a very nice safety ground though! Much better than a simple ground rod. So if possible, put them in both places! Then you have a properly constructed antenna, and a good safety ground. If you can only do one or the other, put'em at the antenna's feed point.
- 'Doc
 
morning everyone i have a couple questions maybe i can get advice on i have an old aluminum ground plane that i recently just saved from the junk pile . now that it is all cleaned up and ready to use i have some questions on it performace. well ideally it would be great to mount this antenna on the roof which would have put it at a little over 1 wave lenght above ground(27 mhz) . but this is not an option due to renting . but i was told that i could mount it next to the gerage . the antenna will mounted on a 1 1/4 tv mast i have the base about 16 feet above ground which i beleive would put it a little under 1/2 a wavelenght. my 1st question is there is 16 feet of antenna mast which is on the ground do i need instulated this tv mact from the the ground . 2nd ? is how much differance will the angle of radtion be at 1/2 a wave lenght abovr ground compared to to 1 full wavelenght? also will the toa be differant or the same next ? is i have read a couple pages talking about use elevated ground radials compared to useing ground radial on the ground since the base of the antenna is 16 feet above ground but the mast the antenna is mounted to is sitting on the ground im not sure what type of set up to use or could i use both elevated ground radials (4 of them) and about 20 16 foot radials on the ground well thanks everyone and 73s

I pretty much agree with 'Doc. According to some of my Eznec5 models the TOA will lower maybe 3-5 degrees on raising up to a wavelength, but that depends on the antenna design, the installation, and the surroundings as well. Even so, it will not be like switching a light off/on.

I find in my real antenna experience, that you don't want your antenna any closer to anything conductive than absolutely necessary. I also find that when I mount my antennas close to and with any part of the antenna at or below the roof peak of my home, which is basically non-conductive wood, the antenna also seems to respond with local signals poorly, and you may even see some matching affects. How high is the garage?
 
Is that going to be the absolute most bestest place to mount an antenna? Probably not, but it should work anyway. At the very least, it'll give you something to compare other antennas and mounting locations to and enjoy while you are looking for that 'perfect' place. You do what you can with what you have available. That's what we all do.
- 'Doc
 

dxChat
Help Users
  • No one is chatting at the moment.
  • dxBot:
    Tucker442 has left the room.
  • @ BJ radionut:
    LIVE 10:00 AM EST :cool:
  • @ Charles Edwards:
    I'm looking for factory settings 1 through 59 for a AT 5555 n2 or AT500 M2 I only wrote down half the values feel like a idiot I need help will be appreciated