Whats up with this?

Discussion in 'Ham Radio Discussions' started by KB0MMB, Apr 24, 2012.

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  1. KB0MMB

    KB0MMB Ham Member QRZ Page

    I was listening to 6 meters this morning 50.125 and heard Gene in there K7GZB from Tucson,I was on my 10 meter di-pole in the attic..signal was about about an S3,I made a call to him and he heard me but about the same on his end S3...I switched over to my 5BTV which is not even rated for 6 meters and he heard me better and I heard him better..about s5-7 this time. Did I waste my money putting up the di-pole in the attic?
    My tuner tuned the BTV up just fine 1.5-2 on the SWR.
    The QSO lasted about 2 minutes then POOF..he was gone.
    6 meter.jpg
  2. WA6MHZ

    WA6MHZ Subscriber QRZ Page

    That's the way 6 meters is. DX comes in for a few moments and POOF, they are gone. No time to waste on 6! U need to work the stations as SOON as you hear them. They may only be there for SECONDS! Or it might be a strange day, and the band will be open for hours! That is why it is the MAGIC BAND! U can't predict ANYTHING!!!
  3. WA8LGM

    WA8LGM Ham Member QRZ Page

    Hey! Welcome to "The Magic Band" Six is just that wqy. Sometimes its open and all you need is a verticle in the attic and sometimes even the biggest stack of beams will only get you down to your neighbors's house.
    Anyhoo, have fun on six! Its great.
  4. K9ZMD

    K9ZMD Subscriber QRZ Page

    Since neither of your antennas was designed for 6 meters, your experience shows that any antenna is better than no antenna at all, and that any antenna outdoors performs better than an antenna in the attic.

    On edit: Since your photo doesn't show a 5BTV in the attic, I just presumed it is outdoors. If it is also in the attic, send photo and installation details. Inquiring minds want to know.

    You realize, of course, that your tuner did not actually tune "the BTV up to 1.5-2 on the SWR"? It just tuned the antenna system to present your transmitter with a usable impedance. The SWR out there on your coax was still very high, which means a significant amount of power was lost to just heating the coax.

    If you'd like a better - but low cost - antenna for snagging those 6 meter openings, you can improve the 5BTV performance on 6 by connecting a 1/4 wave wire element for 6 meters to the vertical's feed point. Run it parallel to, but spaced at least 6 inches from, the aluminum tubing. PVC will work as a spacer. With a resonant 6 meter element in place, your tuner won't be needed at all for low SWR, and your coax won't be absorbing so much of your power.

    It would take a little more work & more wire to add 6 meters to your 10 meter attic dipole, but it's do-able. Just connect 6 meter dipole elements to the feed point of your 10 meter antenna and suspend them about 6 inches below the 10 meter elements (making your antenna into a 6-10 meter fan dipole).

    If you did both modifications, you would be able to make meaningful on the air A-B comparisons between two resonant 6 meter antennas. Then the performance difference between the indoor antenna and the outdoor antenna would be easy to determine. You might also discover that there's an occasional exception to the norm, when the indoor antenna outperforms the outdoor antenna. (That's just part of the magic.)
    Last edited: Apr 24, 2012
  5. KB0MMB

    KB0MMB Ham Member QRZ Page

    My bad....thats a 6 meter antenna in my attic not a 10 meter!
  6. KB0MMB

    KB0MMB Ham Member QRZ Page

    By the way..how do I edit my posts on here?:confused:
  7. N2ADV

    N2ADV Premium Subscriber QRZ Page

    There's an edit button for a little while after you post. After that, it may as well be written in permanent marker.
  8. G0GQK

    G0GQK Ham Member QRZ Page

    As a 6 metre antenna is reasonably small, you would be much better having it outside giving it some fresh air, even a V dipole made of wire attached to a couple of garden plant sticks tied to broom handle will bring in some stations. I don't think he has his 5BTV in the roof space unless its poking through the roof tiles !
  9. KC2SIZ

    KC2SIZ Ham Member QRZ Page

    A lot depends on where you live. I once lived in an apartment building and having an indoor antenna was a complete and utter waste of time. Now I live in a woodframe house and can detect no significant loss vs the antenna I have behind the house.
  10. KB0MMB

    KB0MMB Ham Member QRZ Page

    Is your antenna in the attic also?
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