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signal loss using RG8x with couplers?

Discussion in 'Amateur Radio Antennas' started by xtranaut, Dec 29, 2011.

  1. xtranaut

    xtranaut Member

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    Setting up a 10m dipole w/balun in attic and am going to feed RG8x across 30 feet and down into the wall of my den. I already have 50 ft of coax but will need another 50 and am wondering if using a PL259 female to female coupler will give me any significant signal loss?


     

  2. Beetle

    Beetle Sr. Member

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    Run the coax as near to 90 degrees from the wires for as far as possible.

    Every bit of coax adds to the transmission line loss, and every adapter does, too. Is it "significant"? That's your call. Are you sure you're going to need 100 feet of coax? If you run the cable to where you want it and you still have 30 feet left over, cut it to length and install your own connector.
     
  3. RatsoW8

    RatsoW8 Supporting Member, W9WDX ARC Member - WD8T

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    When I was young and broke I would piece together several lengths of coax with couplers. The loss is negligible at hf frequencies so don't sweat it.
     
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  4. Marconi

    Marconi Usually if I can hear em' I can talk to em'.

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    Both Ratso and Bettle are right IMO, but Ratso makes a good point. I don't think you'll be able to tell unless your antenna system is very reactive.

    I can't say there will be a big difference in performance, but the better match you are able to get with your dipole the less likely you are concerning the common mode currents. The less CMC, the less likely you will need a balun, but installing one on a dipole should not make a noticeable difference either.

    Height probably makes the biggest difference using a dipole, and to a point higher and in the clear is better. So, being in the attic might cause some issues. It's trial and error time.
     
  5. Happy_Hamer

    Happy_Hamer Administrator
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    Do you have antenna restrictions near you in Texas?

    Are you installing in the attic so you can hide the antenna?

    What radio?

    Why only 10 meter, do you have room for a larger antenna?

    Do you plan on running an amp?

    Are you using an antenna tuner?

    Have you considered twin lead instead of coax?

    I know someone in Texas that is selling an Astron 70 amp power supply if you are still looking for a power supply, he is on this forum.
     
  6. hookedon6

    hookedon6 W9WDX Amateur Radio Club Member

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    BINGO!,.....
    and don't listen to some of people that tell you to adjust your coax length for the "best" vswr.
     
  7. Captain Kilowatt

    Captain Kilowatt Professional Amateur
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    The extra 50 feet of cable you install will have more loss itself than any connector you use to couple the pieces together.On VHF/UHF this is a different thing but for CB go ahead and install a dozen connectors and you will not see any difference in signal.
     
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  8. GnG8d

    GnG8d Well-Known Member

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    I think I read somewhere once that a 239 connector @28mHz is less than .01dB loss.
     
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  9. xtranaut

    xtranaut Member

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    I sincerely thank you all for helping out. Sometimes you can over think something or get sloppy and regret it too. Unless I move my dipole closer to the wall that I'd have to drop the feed line through, I will be dealing with 100 ft to get there and to the tuner and that could be minus 10 or 15 feet when it's done. I just didnt want to use a PL coupler if, thru experience, it is shown to have significant signal loss. I got a good picture I think

    That is a brute. which? the RS or VS? Meters? I am only doing 25 watts on the HTX... 130 on SSB on the GTL but if I ever get it all set up (find the room) the 830 might could use that ASTRON in long-winded jawjack mode. Kind of budgeting on PS too and thinking about the Alinco switcher. Despite all the NOs on switchers for HF, I have read very good reports on this supply and it is only 130 bucks on sale right now. How much does he want for the Astron?
     
  10. RustDemon

    RustDemon Active Member

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    hionestly I went from 30 feet of coax to 130feet with 2 barrel connecters in the mix to put the pieces all together an did not notice any signifighant difference in my set up when I switched from out in my garage to in my office with all the extra coax and connecters. obviously there was an increase in feedline loss due to the added lentgh but it isn't noticeable to me.
     
  11. Prime Number

    Prime Number Rye drinkin' CB Fiend

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  12. Captain Kilowatt

    Captain Kilowatt Professional Amateur
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    I use PL-259 connectors all the way up to 2m without an issue. I am sure I could gain an extra dB if I used type N connectors but what will an additional one dB do for me into the repeater? Nothing is what it will get me. However if I was more into 2m SSB weak signal work that extra one dB may be the difference between a new grid square or not.When the new antenna system goes up in the spring I will use PL-259's on HF and likely 6m as well but I will likely use type N connectors on 2m at least for connections outside the shack as I have a lot more type N connectors for the LDF4-50 heliax cable I will be using than I do PL-259's. It makes sense to use them where it will make the most difference.
     
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