AIS range issue solved

Blue Note
Marco M.
Mon 24 Jun 2013 22:15
Today at Lagos Marina, I tried to address the issue to the AIS range fluctuating between
~15-20 miles to ~100 miles.

First I tried to look at the PL239 connector between the AIS box and the LMR400 cable.
It looked fine and in excellent conditions.
Tried to disconnect and re-connected it. I had already done this back in late April when the problem first appeared and just like back then: no change.
Then I went aloft with a new VHF antenna: a Metz Manta-6, 34 inches VHF antenna.
As I was disconnecting the VHF cable from the old antenna (a Shakespeare) I suspected that the problem perhaps was with a poor ground connection between the cable and the antenna since there was some "green" oxidation. I replaced the antenna wit the new one.
Add silicon dielectric at the cable-antenna connections and sealed all with Self Amalgamating Tape

Went down and the AIS was now showing (boat at a marina in Lagos) 60+ boats, with boats as far as Gibraltar.

We will see if the good AIS range will stay.
I will keep the old antenna (that I think is still ok) as spare.