HELP.. 80 meter antenna

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by AC1DV, Nov 27, 2019.

ad: L-HROutlet
ad: l-rl
ad: Subscribe
ad: Left-3
ad: abrind-2
ad: L-MFJ
ad: Left-2
  1. AC1DV

    AC1DV Ham Member QRZ Page

    OK.. forget my last post.. I'm looking for suggestions for an 80 meter antenna. I need it predominantly to speak north to New Hampshire. I'm in RI. I have a vertical for 80 now and it doesn't make the trip easily. I have about 110 Feet of space to run a croocked dipole.. However the killer is it's only 15 feet off the ground. I may be able to buy another 10 feet for the center if I get creative. I'm open to suggestions..
     
  2. KK5JY

    KK5JY Ham Member QRZ Page

    NH to RI on 80m is definitely an NVIS path. I have used both low dipoles and STLs for this purpose, and both work very well at less than 100W.

    The low dipole I used was loaded at 80m, and it still had good signal levels at that range: http://www.kk5jy.net/dx-dd-clone/ That can be helpful if you have limited space. Only 15ft off the ground should not be a problem, as long as both stations are using low dipoles.
     
    KU3X likes this.
  3. KM4DYX

    KM4DYX Ham Member QRZ Page

    Horizontal loop at 15 feet on 80 will get you into NH all day long.
     
    N5PNZ and KK4NSF like this.
  4. KM4DYX

    KM4DYX Ham Member QRZ Page

  5. KH6AQ

    KH6AQ Ham Member QRZ Page

    If you'd like a shorter dipole that will fit into the space a shortened dipole such as the MFJ-17758 or Diamond W735 40/80 meter dipole will fit. Total length is 85 ft.
     
    Last edited: Nov 27, 2019
  6. W1VT

    W1VT Ham Member QRZ Page

    A simple Inverted-L should work when you have short skip propagation. But, you are far enough North that the band won't be open in the evenings. Maybe in a few years when the solar flux is higher, but not now.
     
  7. KU3X

    KU3X Ham Member QRZ Page

    Could not agree with the above statement more.
    You need a shortened dipole. Hy Power Antenna Company makes an LD8073 which is an 73 foot long resonant dipole for 80 meters. Once cut for SSB, I think the length becomes only 68 feet long. A few years ago QST did a product review on this antenna.

    Good luck,
    Barry, KU3X
     

    Attached Files:

  8. AC1DV

    AC1DV Ham Member QRZ Page

    Thanks much for the response. This is good info. I have room for about 110 feet of length..(with a big bend in it) I'm not very talented with coils. Past attempts haven't ended well.. If I just ran a dipole at my max length do you think it would tune with a tuner?
     
  9. KK5JY

    KK5JY Ham Member QRZ Page

    Probably... we would need a few more details to know for sure. I'm not a big fan of running high SWR on a coaxial cable -- I prefer resonant antennas or remote matching. The antenna I linked above is less than 90' long, so a loaded resonant antenna will definitely fit in the space you have.

    It could be that part of the struggle you are having is line loss from using a desktop tuner on a nonresonant antenna? On 80m, losses don't add up nearly as fast as they do on 20m or higher, but they do add up. If you can get the antenna resonant, it will take one variable out of the equation -- namely the extra loss from all the reflections.

    If you don't want to wind your own inductors, you can get ready-built inductors and whole antennas. The DX-DD I linked to above is certainly an affordable antenna if you don't want to wind your own. There are plenty of other ready-made loaded antennas for 80m out there.
     
  10. WB8NQW

    WB8NQW Ham Member QRZ Page

    Google AS-2259 GR. This is a 80/40 NVIS military antenna. There is a modified version with coils near the feed point that puts the resonant frequency in the ham bands. Our club built one for a special event and it worked well.
     

Share This Page

ad: ProAudio-1