RX and TX with a big dish (1.8m) without kill the lnb !!!

  • Good evening,

    I have a question , I want to use this setup :

    - Dual band feed DJ7GP with lnb octagon

    - PA 4W

    on a 1.8m dish. But I wonder about the insulation of the lnb when I transmit. Does the high power of 2.4 Ghz can create fatal harmonics for the 10Ghz lnb and kill it ?


    Chris, F4FLU

  • Obviously, the 2.4 GHz itself cannot enter the LNB due to waveguide cutoff. 4x2.4 GHz = 9.6 GHz, which is a theoretical possibility.

    But assuming you stick to the legal power limit on 13cm and drive the final amplifier not too recklessly, the harmonics should be far below any danger limits for the LNB. You want to use a 4 W amplifier presumably for SSB so you would need to back off a bit anyways. And then, I don't think harmonics are a problem.

    Have fun!