I bought the bottom of the range NASA navtex receiver. I was reading with interest the article in PBO this month about navtex. According to the piece it is possible to receive inshore forecasts on dual band models only ... or have I read it wrong? I am assuming that the navtex I have doesn't have both bands. The destructions that came with it are far from comprehensive. I am most interested in inshore forecasts at present. Can any one shed more light on this?
NAVTEX
- Thread starter Ralph
- Start date
You are right - Navtex is transmitted on two different frequencies. 518 kHz is the 'International' frequency - broadcast in English and 490 kHz is the 'Local' information, broadcast in Local Language (English).
518 contains Shipping forecast type weather (twice a day) plus all the (useless) navigation warnings. In the UK 490 is used for inshore forecasts.
The earliest/cheapest receivers only receive one frequency (518); in most cases it is possible to add a second antenna to these to pick up the second frequency. The next level up can receive two frequencies, but only one at a time with manual switching between them. The best receivers will receive two frequencies at once.
The problem with manual switching is that you have to keep switching it between broadcasts. So if you want both the Shipping forecast and the inshore forecast to plan you day's sailing you have to get up sometime arround 0600 to switch from 518 to 490.
From what you say you have a receiver that will only receive 518 kHz - I believe you can buy a second antenna (or a dual frequency antenna) to allow you to switch manually between the two - I suggest you go back to the dealer and ask their advice.
518 contains Shipping forecast type weather (twice a day) plus all the (useless) navigation warnings. In the UK 490 is used for inshore forecasts.
The earliest/cheapest receivers only receive one frequency (518); in most cases it is possible to add a second antenna to these to pick up the second frequency. The next level up can receive two frequencies, but only one at a time with manual switching between them. The best receivers will receive two frequencies at once.
The problem with manual switching is that you have to keep switching it between broadcasts. So if you want both the Shipping forecast and the inshore forecast to plan you day's sailing you have to get up sometime arround 0600 to switch from 518 to 490.
From what you say you have a receiver that will only receive 518 kHz - I believe you can buy a second antenna (or a dual frequency antenna) to allow you to switch manually between the two - I suggest you go back to the dealer and ask their advice.
