Navtex memory

[yacht1948]

I am training in Germany sailors in SRC courses.
And I would like to start the Navtex lesson with an example "Sailing from German Bight to Scotland"
We have in Germany only one Navtex station in Hamburg/Pinneberg.
So the risk of a memory overflow is low, even with old receivers with a storage of 200 lines.
The Navtex Pro has a memory for 800 lines.

In UK there are several stations
e.g. on 518 kHz Niton (E), Portpatrick (O), Cullercoats (G), Valentia (W), Malin Head (Q)
even some of them with different areas and outlooks.
Is there in real live a risk of a full memory when not deselecting some of these 5 stations?

I have not found a map showing the overlaping radio horionts of the stations.
Is there a high degree of overlapping, so I will get a lot of similar messages from several stations?
Thanks, Wilhelm

 

[Lucky Duck]

On the East Coast of the UK I get both Niton and Cullercoats but most use 490 kHz as this gives the inshore forecasts and local weather condition reports.

Haven't had memory issue with my Furuno unit, by the time transmissions are no available they are usually several weeks old.

 

[earlybird]

If the memory of my Furuno NX300 becomes full, the oldest messages are progressively deleted. It doesn't stop receiving new messages. I think that the NASA is similar.
Stations are situated to give best coverage of the specific Nav. Area. The 3 stations in the UK give some area overlap, but not a great deal. They might be received well outside their area coverage however.
If stations are not deselected, and reception conditions are good, then the memory can fill fairly quickly with information that is not relevant to your area..

 

[srm]

As a general rule the oldest lines are dumped so you will always have the latest information recieved. This was the case with the NASA sets, and I think is so with my Furuno, however I regularly delete the messages so as not to have too many on the display list.
Good practice is to select the type of messages you want. In my case weather buletins and warnings + GPS warnings. SAR normally can not be blocked. This will significantly reduce the number of messages received. As mentioned you can also select the stations you want, which avoids clutter from overlapping stations and those arriving by skywave at night.
In practice I am only interested in the latest weather info for my cruising area so loosing older messages is no great loss. I also 'back up' weather messages by writing them in a dedicated note book + source and date time, ie NAVTEX, Coastguard, Broadcast station etc. as this is easier to refer to when needed.