Navtex 490Khz

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I've been on the boat for a few days and notice that my Navtex receiver is no longer picking up the inshore waters forecast from Niton I on 490Khz.
I have not made any changes and it is still set to pick up Niton I. Just wondered if anyone else is having problems?
I am in the Falmouth area.
Good Navtex link here btw.
I appreciate that I can get the info on the web.
 
Thats an oddity because if the set is working on one frequency there is no reason why it shouldnt work on the other. And because the frequencies are so close together it cannot be an issue of propagation.

Suggest you wait a day or two and see if you can get other 490 stations. If you can the prob is with Niton. If you cant, then likely it is the set.

Which when you think about it is a statement of the bl***ing obvious, but I'm trying to help! /forums/images/graemlins/grin.gif
 
Thanks for your reply.I am hoping it is not the set, ICS Nav6. Not many people around so can't as yet see if it's a local problem.
 
Have received inshore forecasts on 490kHz from both Niton and Portpatrick this evening form my location ashore in East Dorset on a a non-dedicated comms receiver and a bit of wire outside for an antenna. Your problem is most likely some local interference, which could be generated onboard by other equipment or other neighbouring sources.
 
Thanks, at least I know now the forecasts are being transmitted. Will ask around locally to see if it's just my problem. Thanks again.
 
Yes I have a fridge, but it doesn't pickup Niton either!
Are you suggesting that it may be interfering with the 490kHz signal?? Will switch it off. Perhaps it does pick up Niton!
 
Niton did change its designated letter - as it conflicted with another station near enough to cause trouble.

Are you sure you are set to correct Niton letter now ? As I think the original letter was given to the other frequency.

Can't remember new letter - but that was my problem ... I had no data coming in either - till another told me !!
 
Re: Navtex 490kHz

Thanks Nigel, am aware of the change. It's not the fridge or other instruments. I have rebooted it, so I'll wait and see.
 
Re: Navtex 490kHz

My Nav 6 misses forecasts on 518 and 490 from time to time, gave up trying to guess why a long time ago, assumed it was poor aerial or location or... /forums/images/graemlins/mad.gif
 
I have an ICS Nav6 and very recently I have had nothing from Niton on 490 or 518 for odd days. I have mine set to show only 1 days worth of info from Niton only and on a recent visit to the boat the display was blank. Changed to show 2 days and the previous days messages were there.

Next day, got a couple of messages but not the usual number. I wondered if Niton were having transmitter trouble as when I re-selected other stations on the Nav6, there were messages from them for the days when Niton had nothing.

Cheers,

Jerry
 
Re: Navtex 490kHz

Raymarine's RN300 GPS and Raychart 320 plotter can both produce severe EMI when a Seatalk connection is made, which wipes out 490kH Navtex reception. The frequency of the EMI drifts with temperature so the interference can be seasonal. I don't know of other possible problem sources but the Nav6 display itself interferes with both GPS and marine VHF reception if the antenna is too close. ICS decided not to do anything about it. I also get 490Khz reception problems when our usual marina neighbour has all his electrics/electronics switched on, not suprisingly he complains about his own reception too!
 
Re: Navtex 490kHz

Thanks for that. Hopefully it is due to interference, though I tried switching off all my stuff to no avail. Perhaps it will be ok when I move out of the marina to the summer mooring.
I am very close to the marina WiFi transmitter, could it be that?
 
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