Aerials

[ghostlymoron]

Which antennas, GPS mushrooms, NASA SSB and NAVTEX cannot be positioned close to each other and what are the best positions. I have AIS, VHF and AM/FM sorted.
The Vesper Marine splitter is awesome.

 

[William_H]

There should not be any problem with Navtex being anywhere. Do I take it NASA SSB is receive only in which also no problem. If it is SSB trnasmitting then best keep it well clear of other antenae. I would never have advocated a splitter for VHF and AIS as it is far better to fit an emergency VHF antenna on stern rail and use that for AIS. good luck olewill

 

[ghostlymoron]

Thanks olewill, I asked this question on behalf of a friend, Cobblers just has a handheld vhf. He's not going to be pleased with your comment on the splitter - it cost him £200!

 

[Billjratt]

If the splitter works it's OK but you have multiple eggs in basket syndrome, one seagull clouts one aerial = nothing works.
As our antipodean cousin says, keep the receiving aerials away from anything that transmits (or other noisy radiation - LEDs, flourescents, motors etc.) The SSB would be on the backstay I guess - even if it's only a receiver, they like a nice long wire. Emergency VHF aerial is great for AIS, and should be mandatory IMHO.

 

[ip485]

I doubt the SSB will cause any issues fitted with a good tuner - its at a totally diffferent end of the spectrum. I did wonder whether despite this is could be an issue but my AIS, TracVision and SatCom are all just in front of the backstay and there is no interference at all when transmitting on full power - 150w.

 

[rob2]

Any and every manufacturer will advocate mounting at the masthead for maximum range, even on receive only, but there is never enough space is there? Chosing which get the priority position will depend on your sailing area as to which is more important to you. All you can do with a selection mounted on the rail is to do your best to maximise separation (both horizontal and vertical) and check for any strange behaviour. You shouldn't get any direftional properties, as the individual aerials are not directly interconnected so shouldn't act as reflectors unless you're very unlucky with the separation happening to be tuned to the frequency in use, but you might conceivably find that one will shadow another. Having said that, I sailed on a boat with a stub aerial at the masthead mounted upside down so it was alongside the mast! Performance was excellent and we never knowingly missed any calls or failed to make ourselves heard.

So many boats are seen with the rail or arch bristling with antennas and we don't have many threads trying to sort out why they're not working.

Rob.