Aerials

[Cspirit]

On my new boat I have a very substantial (2 metre high) mast attached to the stern rail which the previous owner used for a wind vane that has now been moved to the mast head. I'm thinking of altering it to take some of the boat's aerials - GPS, Navtex, spare VHF/AIS and, umm, television. Will I have any problem simply spacing these out along a half metre bar at the top of this mast, or will any one of these aerials adversely affect any other?

 

[Alex_Blackwood]

The only problem with that arrangement would be if you transmitted on the VHF. As all the others are receiving aerials there will be no problem. GPS "Active" aerials are prone to damage from nearby transmissions.

 

[steve_cronin]

Doubt it very much....

...as I have the same set-up. However, if you're going for a Glomex saucer type TV aerial, I would consider mounting it at the masthead otherwise it will only work without receiving shadows when well away from other yachts' rigging such as in a marina or berthed alongside. This will also allow you to set the spare VHf at the opposite end from the GPS as some sets are claimed to be sensitive to strong High frequency signals. The usual guide distance is 2ft of which your 500mmis a little shy.

Some will claim that the GPS ought to be a close to the boat's centre of rolling so as not to introduce errors. Well that would be true if you were signed up to the surveyors' enhanced system but it isn't going to make as much as a single British Standard Gnatscock's worth of difference. Also, although it IS possible to receive Navtex as claimed by the makers "...with the antenna in a saloon locker" I would (and did) get that well up and out into clean air too if you want to avoid missing significant letters or even a whole broadcast because the tide has your aerial down behind the harbour wall - it is not a strong signal and is easily corrupted.

Steve cronin