ad: ProAudio-1

Hustler 4-BTV close to building

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by SP6MI, Mar 28, 2021.

ad: L-HROutlet
ad: l-rl
ad: abrind-2
ad: Left-3
ad: MessiPaoloni-1
ad: HRDLLC-2
ad: L-Geochron
ad: Left-2
ad: L-MFJ
  1. SP6MI

    SP6MI XML Subscriber QRZ Page

    I going to buy Hustler 4-BTV antenna and only place (close to shack) is very close to building - something about 1-1.5m from wall. Building is something about 8m height. Other option require more than 50 meters of coaxial, and working only with 100W I'm afraid that such ammount of coax will suppresses power delivered to anntena.
    Does anyone of you has tested such installation with this antenna? Will it work efficiency, or it's better to install it in second place with >50m of cax.

    Marcin SP6MI
  2. NN4RH

    NN4RH Premium Subscriber QRZ Page

    The trade-off is cable loss versus signal loss and pattern distortion being close to the building.

    50 meters of RG-8X cable has a loss of 1.93 dB on 14 MHz with an SWR of 2:1

    Adding another 10 meters of cable, to get the antenna 10 meters away from the house (farther is better), increases the loss to 2.29 dB, an increase of 0.40 dB. You'll never notice that.

    That extra 10 meters is going to remove you from RF noise from all the electronic gizmos in the building, reduce the likelihood that your transmissions will interfere with stuff in the building, and will allow you to put down a full 360 degrees of radials that will improve efficiency and lower ground losses, lower the take-off angle, and make the pattern more uniform.

    Are all those benefit worth an extra 0.4 dB of loss?

    (For context, an "S unit" of signal strength is typically considered to be about 4 to 6 dB).
    KI5WW and AK5B like this.
  3. SP6MI

    SP6MI XML Subscriber QRZ Page

    Thanks for quick reply.
    I was going to skip radial, since ground has very good conductive (shallow groundwater). I though about RG-58 or RG213 (58 in close building placement, 213 with second option. And sorry I forgot to add in my first post does mesh fence closer than 1m from antenna will be problematic.
  4. WA0CBW

    WA0CBW Ham Member QRZ Page

    Yes. That close it most likely will. Minimum would be a clear area with a radius the same as the height of the antenna. Same for the radials.
  5. K8JD

    K8JD Ham Member QRZ Page

    Skipping radials will cause the antenna tuning to be off and increase SWR and increase losses.
    A step backward.
    I would add radials, as many as practical, and carefully adjust the antenna per the manual to get lowest SWR.
  6. N1IPU

    N1IPU Ham Member QRZ Page

    Word to the wise. Whatever your install you will need to install a common mode choke at the antenna and possibly at shack entrance or you will have issues more often than not. I would mount it as far away from structures as I could and if ground mounted at least put down wire fencing around it if not radials. You will be disappointed if not. I'm a big fan of the BTV series and run a BTV as primary after a severe windstorm wiped everything else out. Mine is roof mounted of to one side. Using metal roof as reflector and I work all over the world with it.
    Only issue I had with this one was a security cam would blank out on 40m. A snap on torrid solved that. I use a balun designs common mode at the antenna and a wrap at the shack entrance and it works very well. Take the time to do it right and you will be pleased.
  7. SP6MI

    SP6MI XML Subscriber QRZ Page

    Thanks for a pice of a advice, I thought it will be much easier to install this antenna. But still I want it, and I have to install something instead of delta loop, which must be removable each time when we have strong wind (above 40km/h)
  8. WB5YUZ

    WB5YUZ Ham Member QRZ Page

    Lots of people try this, but almost everyone eventually puts in the radials. Even with very good ground conductivity, radials usually work better.

    You will do yourself a favor if you try it both ways before making a final decision. You can lay 15 radials out temporarily on the ground, or use two or three elevated ones, and switch back and forth between the radials and the ground rod or whatever. What you hear when you switch will tell you what to do. And remember, if background noise goes up but signal levels go up the same amount, that means the strength of your transmitted signal will probably be increasing the same amount.

    Good luck an hope to hear you on the air with it!
    AK5B likes this.
  9. WS9K

    WS9K Ham Member QRZ Page

  10. SP6MI

    SP6MI XML Subscriber QRZ Page

    Maybe I'll convince wife and she agree to mount it in the middle of garden... more space even for some radials. Thanks for link, I'll read it carefuly
    WB5YUZ likes this.

Share This Page