"Glenn Ziolkowski" wrote in message
...
Amateur grade antennas do not have the mechanical durability to
withstand typical repeater service. Likely what you have is
wind-induced stress at some internal mechanical connections that
manifests itself as the crackling noises.

Have you ever taken apart a Station Master or Phelps Dodge commercial
antenna? Neither one of them is internally very different from my $79.95
Workman brand knock-off of a Comet or Diamond. Antennas are antennas,
whether they are being used for a police dept. repeater or seldom used
amateur packet station.

I agree on your assessment however. The culprit is either loose joints or
water. I'd dismantle the thing and braze every union in place and then
waterproof the casing joints with Seal Tight upon reassembly.