Join Date: Oct 2006
Location: on the boat - Chesapeake
Thanked 158 Times in 141 Posts
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Re: AIS / Marine Traffic
Talked to an engineer at Si-tex. Seems like you need an SWR on your antenna that is less than 5 to 1. Interference from metal near the antenna ( like on the pushpit)is a no no also. I hooked up to the mast head antenna and all is well. With a laptop plugged into the USB on the AIS you will get a readout on the current SWR after you get the fail light or after a few minutes if all is well. Seems like your vhf radio will T and R on a pretty lousy antenna.
There is no excuse for an VSWR as high as 5:1.
I'm not sure what "interference from metal near the antenna" means. There can be shielding and directive effects, but not interference. The near-field effects of metal near the antenna at the mast head and on the pushpit is not significant, absent "junk on the back."
Just because the equipment functions doesn't mean it is performing as you expect.
sail fast and eat well, dave
beware "cut and paste" sailors.
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