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What coax should I use for my VHF and up station

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by KD7VEA, Jan 21, 2021.

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  1. KD7VEA

    KD7VEA Ham Member QRZ Page

    I am getting my gear back on the air after a few years of not having the time for radio. all new radios, and mostly new antennas, so I figured It was time for new coax. I have a 75 foot Beldon 9913 cable that I bought a few years ago for my 1.2ghz radio, so that will be reused, but I need coax for my 6m/2m/1.25cm/70cm antennas. I have figured I need 75 feet to give some room for the rotator and a little slack on the other end, and would like to keep it under $100 per cable (less would be better) what are my options for semi-affordable, low loss flex coax?
     
  2. KU3X

    KU3X Ham Member QRZ Page

    How much loss is acceptable to you?
    First choice would be hard line.
    If you are just trying to work a local repeater, probably 9913 is acceptable.
    I have used RG 8X on a 2 meter vertical for many years on a 2 meter vertical and was able to use all of the local repeaters. That was good enough for me. I was a happy camper.

    Barry
     
  3. KD7VEA

    KD7VEA Ham Member QRZ Page

    I would like to keep the loss minimal, but hard line is going to be out of the price range pretty quick. The 9913 works good enough for 1.2ghz, and I’m only working terrestrial stations with this setup, no EME or anything where I need to squeeze every last fraction of a DB out of it. I would like to get into EME at some point, but I’ll tackle that project when the time comes. I am seeing cables that Ive not seen before, like Wilson-400, I guess it’s basically LMR-400, but not seeing a flex version. If my desk was on the other side of the room, I could do 50 foot runs and simplify everything, but I’m. It sure I want to tackle that project either.
     
    KU3X likes this.
  4. KD8DEY

    KD8DEY Ham Member QRZ Page

    a few feet of lmr-240uf to handle rotor movement, then attached to something else for the main run, Or just a full length of the LMR-240uf...(should be fine)
    whatever you feel comfortable with....
    I'm using an LMR-240 copy on my Arrow J-Pole. (Its a pre made 50 foot length that I need to get around chopping off about 15 feet)
    and RG-8x on my Dipole (Weight Consideration) It's also a bit more flexible than the LMR-240...
    a few feet of RG-8x instead of LMR-240 for the rotor might actually be a better choice because of the flexibility, and the loss would be insignificant with such a short piece..

    of course you have power handling to take into consider if you plan on using an amp......
     
  5. KF5LJW

    KF5LJW Ham Member QRZ Page

    Not to worry, let your wallet decide. If the wallet does not object and allows you to have something to say; you would determine how much loss you can tolerate at the highest operating frequencies. Ideally something like 2 dB or less.

    Look at a coax loss chart and find the loss at 100-ft loss @ 450 Mhz. Just be prepared for your wallet to veto your decision and goes with another coax like the one you already have. :D
     
    Last edited: Jan 22, 2021
    AK5B and WD4ELG like this.
  6. N7WR

    N7WR Premium Subscriber QRZ Page

    Are you using multiple radios simultaneously? If not buy one run of the very best coax you can and use a remote switch to switch between antennas. Even with the cost of the remote switch, cable for it, and jumpers to the various antennas you would probably save money. LMR 400 coax would be my choice
     
  7. KD7VEA

    KD7VEA Ham Member QRZ Page

    Thanks kf5ljw for the chart link, I was having a hard time finding a good chart. It looks like 9913 and LMR400 have very similar specs on loss. At 2.7db loss at 450mhz, it looks like those are my choices. And the price is right there at the top end of my budget between $80-$100 for 75 feet.
    N7wr, this set up will be used for contesting, so I will be running at least 6/2/432 simultaneously, so the remote switch doesn’t work for this set up.
     
  8. KD8DEY

    KD8DEY Ham Member QRZ Page

    you still might want to consider something a little more flexible near the rotor...A few feet of "ultra Flex" attached with a barrel connector...
     
    WD4ELG likes this.
  9. KD7VEA

    KD7VEA Ham Member QRZ Page

    That’s the plan, I can get 9913 ultra flex for $100 for a 75 foot run.
     
  10. KD8DEY

    KD8DEY Ham Member QRZ Page

    Never heard of 9913 ultra flex. must be a newer development (I'm getting behind the times)....
    been a while since i looked at coax..
    having crappy eyesight, I have come to admire the newer developments in Coax connectors though.
    Newer clamp on vs crimp on or solder on & adaptors...

    I would love to see somebody come out with a clamp on with a crimp on center pin vs a straight crimp on, where i would worry about a good shield connection
     

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