Will,
I remeasured the XM240 at the shack end of the 70 Ohm hardline using
my MFJ259B. The 2:1 VSWR points are at 6.94 and 7.17 MHz for a 230 KHz
bandwidth. Minimum VSWR was 1.2 at 7.060 MHz. (Again this is using
CC's CW - 7.025 MHz dimensions) This is close to the 260 Khz you have
experienced on the 402CD.
Chad and I measured his XM240 with it pointed straight up and
approximately 12' off the ground tuned with the K7LXC dimensions ( A=
251", B= 260.5") with a MFJ259B. The approx. 2:1 points were 7.007 and
7.248 Mhz for 241 KHz bandwidth. Minimum VSWR was 1.1 at 7.105 MHz.
I climbed the tower last night and successfully managed to moderate
the differences in horizontal alignment by redrilling the boom pinning
bolt holes. From the ground it is hard to tell that the elements are
out of alignment. Certainly the RF can't tell the difference. The band
was again noisey last night making weak signal RX poor. Got through to
a RY3 in Moscow on the first call in a small pile up with only 100 W and
599 reports both ways.
73, Fred KG9X
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