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built my first wire dipole this weekend, few questions before i tune it

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so i finally stopped procrastinating and just built a simple half wave dipole for 40m out of some 14awg stranded wire i had lying around in the garage. cut each leg to about 33.5 feet based on the 468/f formula and hung it in an inverted V config off a 25 foot mast in the backyard. center fed it with some PL-259 coax i had, used a SO-239 chassis connector in a small electrical box as the feedpoint and just twisted the wire ends to the terminals with a bit of solder.

thing is i havent put an analyzer on it yet, the MFJ-259 is borrowed from my buddy and he's dropping it off tuesday. but i fired up the rig anyway just to listen and i was picking up stations pretty clearly on 40m last night so something is working at least.

my question is basically, what SWR should i realistically expect to see when i do check it, assuming the length is in the right ballpark? and if its off, is shortening or lengthening each leg the right approach or is there some other way people usually do it. also wondering if i should be worried about the inverted V angle, the legs drop off at probably 120 degrees which i think is pretty wide but i wasnt sure if that affects resonance much or just the pattern.

anyway first homebrew antenna so go easy on me lol

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your 120 degree included angle is actually pretty good for an inverted V, you dont want it much less than 90 degrees or the feedpoint impedance starts dropping quite a bit below 50 ohms and matching gets annoying. at 120 you're probably looking at something in the 60-70 ohm range at resonance which isnt too bad at all for direct coax feed, your SWR will likely be under 2:1 at resonance even without a tuner.

as for tuning, yeah shortening and lengthening the legs is the right move. if you're high in frequency you trim, if you're low you add. do it in small increments, like half an inch at a time near resonance because it moves faster than you think. the 468 formula gets you in the ballpark but wire type, height above ground and nearby objects all shift things around a bit. 33.5 feet is a reasonable starting point but dont be surprised if it wants to be a foot shorter or something. good first build though, inverted V on 40 is a solid workhorse antenna.

yeah i did basically the same thing last year except i used some random speaker wire i had and it worked fine honestly. one thing i wish somebody told me is to leave yourself some extra length when you first cut it, way easier to trim than to splice more on. i cut mine a little too short the first time and had to do this whole thing with a bit of extra wire and some tape and it was a mess. works fine now but still.

also dont overthink the coax connector situation too much, ive seen guys use all kinds of janky stuff at the feedpoint and it just works. waterproofing it is probably worth doing though if its gonna live outside, i used some self-amalgamating tape over the whole box and havent had any issues through two winters.

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