Navtex aerials

[All_at_Sea]

Does anyone know if l can use my Nasa aerial with the Furuno NX300 navtex unit - this will save me having to climb the mast....

 

[nigelmercier]

Why would you put a Navtex antenna up a mast?

 

[RobbieW]

No idea, obviously they are both designed for the same frequencies but physically they are quite different. I suspect that by connecting the NASA aerial to the Furuno unit, if it works, you will sacrifice much of the sensitivity that differentiates the two products. fwiw, my Furuno aerial is mounted above the push-pit, on a tee off the wind generator post

 

[Leif-J]

And my Furuno aerial is in a locker in the cockpit - no problem so far.

 

[All_at_Sea]

Because l have a ketch rigged boat and lots of running rigging and l don't like things on the rails that can get knocked off so in the re-fit 4 years ago l put it out of the way and up the mast.

Why would you put a Navtex antenna up a mast?

 

[NormanS]

Because l have a ketch rigged boat and lots of running rigging and l don't like things on the rails that can get knocked off so in the re-fit 4 years ago l put it out of the way and up the mast.

Yes, my aerial is on my mizzen spreaders, and gives excellent reception, and is out of the way.

 

[DipperToo]

If I recollect correctly, the NASA aerial needs a +5volt supply which is put on the coax by the NASA head unit.

I has thought (several years ago) about maybe using my old NASA aerial with an ICS unit, but the ICS outputs (if selected) +12v on the COAX which many 'active' aerials require.

Not sure what the Furuno supplies....

 

[All_at_Sea]

Come on there must be a techie out there with the answer

 

[smartcom]

This probably depends on the NASA unit. The Navtex engine and (from memory) the PC Navtex Pro both have radio circuitry in the antenna, so won't be compatible. I think the Furuno is an active antenna, so the coax cable will be sending 5V DC from the receiver to the antenna, in which case the NASA will also have a problem if it is a passive antenna.
Why not phone Furuno to check whether or not it is an active antenna, and then phone NASA to see what type of antenna your model has?
Tim

 

[franksingleton]

Does anyone know if l can use my Nasa aerial with the Furuno NX300 navtex unit - this will save me having to climb the mast....

NAVTEX signals from the stations that you want to receive – ie those within 200 to 300 miles are received by ground wave propagation. The sea is a good conductor of radio waves and an aerial on the pushpit or a gantry will work at least as well as on the masthead.

The only advantage of using the masthead is for reception when in port and surrounded by buildings and other masts. If you look at the specifications for NAVTEX you will see that it is intended for us when at sea. In port you have many other options.

 

[NormanS]

NAVTEX signals from the stations that you want to receive – ie those within 200 to 300 miles are received by ground wave propagation. The sea is a good conductor of radio waves and an aerial on the pushpit or a gantry will work at least as well as on the masthead.

The only advantage of using the masthead is for reception when in port and surrounded by buildings and other masts. If you look at the specifications for NAVTEX you will see that it is intended for us when at sea. In port you have many other options.

It depends of your idea of "port". Many anchorages are surrounded by hills, and have few, if any, other options. In such circumstances, there may well be advantages in having the aerial at height.

 

[franksingleton]

It depends of your idea of "port". Many anchorages are surrounded by hills, and have few, if any, other options. In such circumstances, there may well be advantages in having the aerial at height.

Agreed. But, NAVTEX was never intended for use close to land. It has always been assumed that there were then other ways of getting MSI. That is even more so now with cell phones and data networks.

 

[All_at_Sea]

Spoke to Furuno who say that it won't link - mind you they would would't they?
Might try it first to see if it works and if not rig up the Furuno one (in a locker!).

 

[NormanS]

Agreed. But, NAVTEX was never intended for use close to land. It has always been assumed that there were then other ways of getting MSI. That is even more so now with cell phones and data networks.

That assumption is wrong. I can assure you that Navtex reaches many places that cell phones, VHF, and data networks do not.

 

[franksingleton]

That assumption is wrong. I can assure you that Navtex reaches many places that cell phones, VHF, and data networks do not.

Apologies. I Misread your comment. Revised reply -

I agree your comment. However, that does not alter the fact that NAVTEX is not intended for use in port or close to land. Reception in those cases is a bonus. It is intended for use at sea, beyond the fairway buoy.