ARRL

Secure Site Login

Forum Home - Rules - Help - Login - Forgot Password
Members can access, post and reply to the forums below. Before you do, please first read the RULES.

MFJ 1848 HEX Beam

Jul 9th, 11:03

Lgaley1975

Joined: May 7th 2019, 17:28
Total Topics: 0
Total Posts: 0
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

Back to Top