YAGI ANTENNAS ON THE TOWER

Well we did not expect the TET Emtron 6 el dual drive, short boom, liteweight, wide band beam to win this battle but it has been interesting and more testing is in order. The jury is still out!

6 el TET emtron at 38m and 5 el LFA at 32.5m on tower

TET has dual driven elements on a 6 meter boom. LFA is longer with 5 elements loop driven on 8m boom. Results so far show the LFA to have about 2 S points over the TET…BUT…the LFA has a very sharp bandwidth…about a mhz max..move out of that and things go downhill quickly. TET Emtron holds the bandwidth over 4mhz under 2:1. Both antennas are experiencing interaction and the swr on the tet has increased markedly since the lfa went up under it. We will need to remove the tet and see how the lfa does on its own swr wise. (we know how the tet was doing on its own) We may see an increase in bandwidth. Both antenna are fed with the same type of balun and I think we may need to change the balun on the lfa to a coaxial cable air wound type or a 1:1 current type which we have on hand. Every test so far has had the lfa ahead by at least a couple of S points. I can’t say it is any quieter that the TET at this stage because I am not really noticing much difference noise wise. Program for the next few days is to check the antennas together, change the balun of the lfa and remove the tet so the lfa is on its own.

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3 Responses to YAGI ANTENNAS ON THE TOWER

  1. Daryl 2ZX001 says:

    Hey Dave!

    Bet the TET will come out on top, despite the 2 S-Units the LFA has over it. Bandwidth is no contest, and maybe the gain of the TET would improve with some different element spacing. Just sayin’!

    73,

    Daryl 2ZX001

    • dd182003 says:

      I was thinking that way at first too. So the fact is that although the LFA is stronger on TX and a little bit stronger on RX; I have never not heard anything on the TET that I heard on the LFA. Seems the differences are less on RX than they are on TX. If I was only going to have one antenna up there it would have to be the TET because of the bandwidth. But I have a Stepir coming for the other bands and that will take care of the bandwidth and the interaction as it can be closed up. Soooo the LFA will remain..I think!
      In the next few days we will either turn the TET sideways or remove it down the tower and check the bandwidth of the LFA on its own.

    • dd182003 says:

      You are right! at the end of the day bandwidth will win…when there is nothing on 27mhz we can pop down to 12m or up to 10m.
      The LFA is a narrow band point and shoot device but it does get out well!

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