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    COAX LENGTH...Yes this topic again

    So…I have a question for the gurus here…and yes, it’s the always asked question…What length should I cut my coax? And yes again…I’ve been reading and researching. But I still have questions…remember, I’m just a tobacco spitting M.S. Degree in Biology holding redneck…so don’t criticize me for not reading for my answer somewhere else here on the forum! Lol

    I just ran 200ft of RG213 (VF = 0.66) from my radio shack in the basement out to my dipole in the oak tree. 200ft was at least 30-50ft more than what I needed. So…the extra RG213 that’s lying on the ground all laid out before heading up into the tree, I’m planning to whack it and create myself some jumpers for in the shack.

    In thinking about “tuning” the coax and cutting it to the correct lengths…I’m looking at the ½ wavelength formula 492 x (Velocity Factor) / Frequency (MHz)

    My question is what frequency (MHz) to plug into the formula?

    I operate on 26.735 AM in talking local with my dad and his ol geezer buddies…then I operate on 27.355 – 27.555 LSB. So that’s quite the spread on frequencies. Do I just go with say 27.145 MHz as the freq to use in the formula since by my math is the “halfway” point between 26.735 and 27.145?

    My Math:

    27.555 – 26.735 = .820 / 2 = .410

    26.735 + .410 = 27.145 MHz

    27.555 - .410 = 27.145 MHz

    ½ wave length = 492 x .66 / 27.145 MHz = 11.96 so Round up to 12ft to make it easier

    Then I’ll use 12ft jumpers from radio, amp and meter and the feed coax cut it to whatever interval of 12ft works out for the length that I need from shack to the antenna.

    Does this all sound okey dokey or do the gurus have suggestions / comments from the peanut gallery to share?

    Sent from my motorola one 5G UW ace using Tapatalk

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