Bruce,
This may have nothing to do with your problem, but I am curious if the
loading coils you received from MFJ/Cushcraft with your XM240 are
covered in black shrink wrap or a dark gray epoxy? In July I ordered a
replacement loading coil for an XM240 that was damaged in service. It
finally showed up a few weeks ago. Instead of the shrink wrap like the
old design (pre-MFJ), it is covered in this dark gray epoxy. The epoxy
looks almost like JB-Weld. I haven't had time to test it yet, but
hopefully the epoxy has electrical characteristics that are close enough
to the shrink wrap, that the new scheme still works electrically.
I happen to have a couple of loading coils in my possession from the
predecessor of the XM240, the 402CD, to compare against the new coil.
The diameter, number of turns, and overall length look about the same,
but the points where the aluminum tubing pieces end along the length of
the fiberglass coil form are a little closer together. I need to go
fetch one of the good coils from the XM240 to see how it compares to the
new one as well as the ones from the 402CD. I do know the epoxy coating
is definitely new compared to the black shrink wrap used on both the
pre-MFJ XM240 and the 402CD.
The last time I called MFJ/Cushcraft to check on the order status for
the replacement coil in mid-October, I spoke with Tom who indicated that
the long lead time of the coil was due to staffing problems. He said
that MFJ lost of lot of people during the COVID pandemic and they had
been struggling to replace them. Tom assured me that they had just
trained up some new hires and that I could expect my order to be filled
very soon (which it was).
Good luck with your new antenna.
73, Mike W4EF............
On 11/27/2022 6:59 AM, BRUCE FORD via TowerTalk wrote:
I put a new xm240 together (after a number of parts issues) and when testing it
with a mfj 259 it is resident at 2:7 to 1 at 5926.0 shows 10:1 anywhere else
tried 2 baluns and feed lines. Could this be a 259 issue although it is a newer
one (to replace my very old one) .Has anyone had trouble with the traps/loading
coils they use? First new antenna I have built in 40+ years and it does not
work, very frustrating as this is all just slide together and measure. Any
thoughts would be helpful
Thanks
Bruce K9RO
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