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Lgaley1975

Joined: Tue, May 7th 2019, 17:28 Roles: N/A Moderates: N/A

Latest Topics

Topic Created Posts Views Last Activity
MFJ 1848 HEX BEAM Jul 9th 2021, 12:55 1 5,192 on 9/7/21
MFJ 1848 HEX Beam Jul 9th 2021, 11:03 1 5,001 on 9/7/21
MFJ 1848 HEX Beam Jul 9th 2021, 11:03 1 5,435 on 9/7/21

Latest Posts

Topic Author Posted On
MFJ 1848 HEX BEAM Lgaley1975 on 9/7/21
Hello
I have purchased the 8 element Hex beam antenna
I am having difficulty tuning 30m and 40m on this 8 band antenna
MFJ admitted finally, that they sent the elements out intentionally long.
My original mindset was that the wires would be right on frequency when I assembled out of the box.
That said, I found a document that told me that the 30 M element was 52 ft long (26ft x 2)
My calculations indicate that 10.100 MHZ should be 23 ft 2.75 in and the upper end of the band 10.150 mhz should be 23 ft 1.34 inches vs the 26 feet that I currently have.
My thought is to cut the wires to the longest resonant length, and go with that.
I should mention that I used a comet antenna analyzer and even though I folded 27 inches of wire back on each side, the antenna remained resonant at 9.700mhz and did not change,

Can I follow the same advise for 40 M?
that band is different, the lowest SWR is 2.0 at 7.1 MHZ. I am thinking I need to make that band longer???
This is my last ditch effort to tune this thing, I am in hopes that I can get some guidance before I decide to cut it up into tiny pieces. Thanks
Larry KC4JPD
LIGHTNING STRIKES TO HEXBEAMS K4NMG on 9/7/21
HI I have not heard much about lightning strikes on Hex beams, I just purchased a 1848 from MFJ and I am having difficulty tuning it.
info on Hex beams is scant at best. Would you be willing to talk with me about how to get mine tuned? I just did a post about my difficulties. I am near Mobile Alabama, so I may be close to you !! Direct email is Larrygaley@gmail.com if you have any ideas or have time to school me? Thanks Larry KC4JPD
MFJ 1848 HEX Beam Lgaley1975 on 9/7/21
Hello all:
I purchased a MFJ 8 band hex beam and now that I have it assembled in my tiny lot, I am having difficulty tuning it.
Most notably 30M and 40M, MFJ finally admitted to sending the elements out longer than needed. I was advised to approach the situation as if it was a dipole. The 30 m wire was sent at 52 feet long which I was instructed to cut in half . that means each half is 26 feet long plus an inch or two, way long for 30 meters. My calculations indicate that
10.100 mhz = 23 ft 2.75 inches
10.150 mhz = 23 ft 1.34 inches

What length should I cut my wires ?
I tried folding the wires back on themselves but antenna remained resonant at 9.700 mhz and would not change, this is my last ditch effort on 30 m

40M is another enigma, the best swr I get is 2.0 at 7.150 mhz.
MFJ sent me a 72 ft wire (2 x 36 ft)
My calculations say that the Lower and and upper end of the band should be
7.000mhz 33 ft 6 in 7.300 mhz = 32 ft 1.6 in.

how should I trim my wires? to the long length or the shorter length??

All help appreciated

LARRY KC4JPD
MFJ 1848 HEX Beam Lgaley1975 on 9/7/21
Hello all:
I purchased a MFJ 8 band hex beam and now that I have it assembled in my tiny lot, I am having difficulty tuning it.
Most notably 30M and 40M, MFJ finally admitted to sending the elements out longer than needed. I was advised to approach the situation as if it was a dipole. The 30 m wire was sent at 52 feet long which I was instructed to cut in half . that means each half is 26 feet long plus an inch or two, way long for 30 meters. My calculations indicate that
10.100 mhz = 23 ft 2.75 inches
10.150 mhz = 23 ft 1.34 inches

What length should I cut my wires ?
I tried folding the wires back on themselves but antenna remained resonant at 9.700 mhz and would not change, this is my last ditch effort on 30 m

40M is another enigma, the best swr I get is 2.0 at 7.150 mhz.
MFJ sent me a 72 ft wire (2 x 36 ft)
My calculations say that the Lower and and upper end of the band should be
7.000mhz 33 ft 6 in 7.300 mhz = 32 ft 1.6 in.

how should I trim my wires? to the long length or the shorter length??

All help appreciated

LARRY KC4JPD

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