Ask Sail: AIS Antenna
David Stiller of Miami, Florida asks:
I’m ready to install AIS on my boat. I also need a new VHF radio with digital selective calling (DSC), so I’ve ordered the new Standard Horizon GX-2100 VHF set with an internal AIS receiver. Will this equipment work with my current Shakespeare masthead VHF antenna?
Gordon West replies:
AIS radio signals are carried on frequencies 4.6 MHz higher than normal VHF ship-to-ship channels, but I’ve found a regular marine VHF antenna works just fine. Shakespeare’s antennas feature a half-wave matching network within the base, which furthers broadband reception on the higher AIS frequencies. You can double-check your masthead VHF/AIS reception by tuning in multiple weather band signals. Make sure you hear twice as many signals from your masthead antenna as you hear with a handheld VHF radio down at deck level. Weather band reception occurs on frequencies relatively close to the AIS 162 MHz channels.