> My understanding is that the traps on older Mosley beams can be
> troublesome.
Prior to the purchase, I would assemble the driven element and elevate it at
least 16' above ground. Connect suitable cabling and check VSWR on 20/15/10
meters. This will provide a clue if the traps have been burned. The
reflector and director traps will not be subject to the same extreme heating
that can occur as on the TA-33 driven element. This was a significant
problem for ops such as myself who purchased a TA-33 Jr. as a novice, then
upgraded our licenses to run the full legal limit. Mosley offered the MP-33
driven element in response to the many burned out TA-33 Jr driven-element
traps.
Finally, I would check the integrity of the four phenolic driven-element
stand-off insulators to ensure they are not cracked from UV and/or
over-stress. Mosley used to provide a liquid UV protectant that was applied
with a brush from a half-pint-sized can. It actually did a good job of
protecting the antenna and went on like a varnish.
Other items to check are corrosive and stripped hardware as well as possible
cracks on the black plastic used on the trap ends. Any hardware requiring
attention should be replaced with stainless steel at every opportunity.
Paul, W9AC
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