GPS Antenna: Internal vs. External (?)

[STeveZ]

I am considering insalling Garmin GPSMAP 172C on the flybridge of my 28' Bertram. Is there any reason not to go with the internal antenna? Does the external antenna offer any advantage? I like the idea of the internal antenna's simplicity and the elimination of clutter (antenna/cable) on the bridge. The bridge is covered only by a canvas bimini if that's a consideration. Thanks in advance for your response.

 

[Canuck 16]

Re: GPS Antenna: Internal vs. External (?)

I had the ploter your looking at and could never lock onto a WAAS satelite with it. I replaced it last year with a 182C with external antenna and have never had a problem aquiring WAAS.<br />It may just be my location, but you may want to try it out before you buy.<br /><br />Good luck... Canuck 16.

 

[Boatist]

Re: GPS Antenna: Internal vs. External (?)

I agree the only posible issue would be the WAAS birds. The external antennas are more omni directional and can be mounted where nothing will block there veiw. Do not know your location but the farther north you are the weaker the singal. Actually the farther from the equator you are the weaker the signal.<br /><br />The canvas top is not an issue but your body between the unit and the WAAS bird is. Most internal antennas I have seen are somewhat dirrectional. Since the 2 WAAS birds are 23800 miles up and over the equator they are much harder to receive. Without the WAAS birds accuracy about 10 meters or 30 feet. With the WAAS bird accuracy about 3 meters or 10 feet. Really not that big a difference. The 24 non WASS birds are in low earth orbit and very strong when over head and you will have no trouble receiving.

 

[JB]

Re: GPS Antenna: Internal vs. External (?)

Electronics topic.