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Doublet input needed please

Singularity35

DU7DVE
Jan 16, 2014
425
90
138
Small City, Philippines
Hey antenna gurus, I'm asking for your help again.

I'm planning to throw up a doublet cut at around 130 feet total length and fed with 300 ohm twin lead(tv antenna wire) directly into an mfj949e.

I have two questions. First, would it be better if I use a 4:1 balun on the feedline and not use the internal balun on the tuner? Second, will the flat wire be ok for up to 100 watts?

Thanks in advance for any feedback. Additionally, any thoughts or input outside my question(which I most likely haven't thought of) will be very much welcome.
 

wavrider

W9WDX Amateur Radio Club Member
Jun 2, 2009
3,414
1,293
173
What type of antenna coupler (tuner) do you have?

If the balun is a current balun should work fine
300 ohm twin lead will be fine for 100 watts.
 

BJ radionut

Supporting Member and 6m addict
May 9, 2008
4,217
4,817
373
35 miles East of Indianapolis
S35: The internal Balun in your tuner will be fine and the Doublet cut between 62-65 ft each side will work fine...
Couple things...1: make sure you have your tuner well grounded...
2: when loading the antenna use lower power 15-20 watts till you find the sweet spot on the tuning,,,and once you get it loaded then go full power and "Tweek" it quickly...if needed
Then you should be good to go...
Start you a chart for each band to remember the settings for each place you operate...This will speed tuning up later and save wear and tear on rig and tuner...
Have fun good luck
All ther Best
Gary
 

Road Squawker

Sr. Member
Jan 19, 2011
1,954
1,510
173
...I'm planning to throw up .... Additionally, any thoughts or input outside my question...will be very much welcome.

puking.gif

OK, I just couldn't resist
hide.gif
 
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Singularity35

DU7DVE
Jan 16, 2014
425
90
138
Small City, Philippines
Thank you very much for the quick replies.

How far from metal does my twin lead have to be? My roof and gutters are tin and additionally my window sill is aluminum and the windows have iron grills on them.

Will all that metal be an issue if my twin lead goes directly through my tuner inside the room?
 

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