Did anyone else not know that the newer style UHF yagis are not meant to be level?

Discussion in 'Over the Air TV By RabbitEars.Info' started by miguelaqui, Mar 20, 2016.

  1. When I took a TV on the roof with me, I , just to check, tried moving the XG91 up and down to see if it made a difference. It did make a slight difference.

    I had always been taught that, if the mast was level, the the antenna would have the best reception when leveled. Not the case this time.
     
  2. I've read about some instances where tilting an antenna can aid reception, but haven't tried it myself. How much tilt and how much difference did you see?
     
  3. This is know as the knife-edge effect. When a signal hits a tall object, such as a mountain or large hill, part of that signal is diffracted downward into the shadow of the object. Tilting your antenna upwards a bit often makes it possible to receive a channel that you would not get if it were mounted level. :)
     
    Radioguy41 and Iceberg like this.
  4. And what are you aiming at? Trees or a hill between you and the transmitter. 1edge signal (TVFool)? In those cases aiming towards the offending obstacle top can improve performance.
    Having the antenna 'level' is usually the best if it's LOS.
     
  5. or for DX'ing....
     
  6. only abut 2 db
     
  7. The Stellar Labs antennas, at least the ones I have, have the mounting hardware already set up to easily tilt the antenna. Just a rough eyeball look says max about 45° (up or down depending on the orientation)
     
  8. same with e Solid Signal Xg91 clone.
     
  9. I used to live in Gardnerville, NV back in 1991 was able to get Sac, CA, by knife edges over Lake Tahoe I get KXTV ch. 10 and KCRA ch. 3 with just a rabbir ears on my 13" sony TV! :biggrin I could had put up a good outdoor antenna to play with.:hungry2
     
  10. Antennas direct 91xg 90ft hi. With a 7777,channel Master 80mis out signage of 70 % 01511 ,69.1,ct state and no Dropout's
     
  11. Mine is tilted downward. I spent a lot of time up on the roof adjusting the antenna, cell phone in hand, watching my signal quality meters using the Signal GH iphone app, and to my surprise, the highest gain for all my stations was achieved by tilting my antenna downward. It remains there today.
     
  12. My antennas Direct 91xg ,agl of 10, and your antennas front is in the grund I can see why it took so long to set up