I have just experienced a similar problem with my 4L M^2 antenna
(intermittent SWR variations and non-beam performance) and I
will be taking it down tomorrow to repair/modify it. I have been in
contact with Mike, K6MYC, about the issues and options for mods
(a couple of weeks ago) and have forwarded along copies of the relevant
messages.
For the short term, I will either 1) make new shorting bars today that are
split and cross bolted to make a clamp contact with a large surface
area or 2) make some aluminum rod hairpins to replace the shorting bar
(or in addition to) and attach with split bolts. I have seen aluminum split
bolts but I may not be able to find enough of the right size on a Saturday
to do the job. If I use copper ones I will wrap the linear loading rod and
hairpin with some aluminim foil before applying the split bolts--making the
aluminum foil the sacrificial part of the joint (plus use one of the OX-Gard
type products). May consider doing the job with some small stainless steel
hose clamps if they will go down that small in size.
Any TIG weldingor anything else on the linear loading (and top guy) is sure
to make them more prone to breakage.
73 John
John Brosnahan W0UN
24115 County Road 40
La Salle, CO 80645
Log Padding is a NON-CONTACT sport! (W0UA)
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