I have a M2 4030M4L. The loading wires for the elements came to an aluminum
bar. They used Phillystran from the bar to an aluminum riser above the boom.
Initially the Phillystran was just clamped in the bar as a "U" but that
would "eat up" the Phillystran. Later they had some small round probably
Lexan pieces that you put on the outside of the aluminum bar to wrap the
Phillystran "U" around so the edges of the aluminum bar did not cut into the
Phillystran. Not sure if that applies to 40M3L and if that is what you fixed
Ed. I found it on my antenna before it was even off the ground fortunately.
73 Larry W6NWS
-----Original Message-----
From: Edward Sawyer
Sent: Monday, October 14, 2013 6:31 AM
To: towertalk@contesting.com ; ky5rtim@gmail.com
Subject: Re: [TowerTalk] M2 40M3L Tuning
I have a 40M3L vintage 2005. It is at 80 ft with a 10M 6 el underneath by
10 ft. The nearest tower is 140 ft away.
I found the measurements to be "in the ball park" but not exact. However I
got reasonable resonance points by raising it up 35 ft to the first guy
point of the tower - just don't worry about the SWR, look for the resonance
X=0 line. It went uo in frequency by about 20khz at 80 ft. Mine is tuned
to 7080 and I have 1.6 SWR at 7.000 and 2.0 SWR at 7.210. Like most 40 M
shortened beams, it climbs pretty quickly after that and is about 3.1 at the
top of the band. Plus the gain is dropping off. But for contesting and
DXing CW + SSB, this is a good spot for tuning.
It is a very potent antenna on the bands and a very solidly built antenna
with one exception (if they haven't fixed it). The connection of the cross
bar of the tuning wire to the post on the boom. The method breaks after a
few years. I redesigned mine to eliminate the pinch point that eventually
snapped. Not a fun repair in the air.
73
Ed N1UR
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