NMEA, transducer frequency etc

[roblpm]

Hi

I have a Stowe Dataline system and have added their nmea box which outputs nmea0183.

As the displays are knackered and I don't want to spend any more money on this system that cant be transferred to a subsequent boat I was planning to set up a basic nmea 2000 network so I can buy some raymarine i70 s

So the plan would be to buy an actisense ngw-1 and possibly an ngw1 ais for my sh radio.

Then from reading around it seems that all i need are the cables, t pieces and terminators to build an nmea2000 network. This could all be reused on another boat later.

However someone told me yesterday that the transducer frequency of my depth sounder could cause a problem?

Is this right? Surely the dataline system takes care of this? Does the nmea output have anything to do with the transducer frequency??

I know the nmea is at a particular baud rate, what determines how often the nmea sentences get sent onto the wire?

Cheers

Rob

 

[lpdsn]

Hi

I have a Stowe Dataline system and have added their nmea box which outputs nmea0183.

As the displays are knackered and I don't want to spend any more money on this system that cant be transferred to a subsequent boat I was planning to set up a basic nmea 2000 network so I can buy some raymarine i70 s

So the plan would be to buy an actisense ngw-1 and possibly an ngw1 ais for my sh radio.

Then from reading around it seems that all i need are the cables, t pieces and terminators to build an nmea2000 network. This could all be reused on another boat later.

However someone told me yesterday that the transducer frequency of my depth sounder could cause a problem?

Is this right? Surely the dataline system takes care of this? Does the nmea output have anything to do with the transducer frequency??

I know the nmea is at a particular baud rate, what determines how often the nmea sentences get sent onto the wire?

Cheers

Rob

The transducer frequency should have nothing at all to do with it. That's the frequency of the ultrasound your transducer emits to bounce off the sea bed. The NMEA0183 messages contain the measured depth, almost certainly at the usual 4,800baud.

The transducer frequency would only be an issue if you were going to have two depth sounders running in parallel.

 

[bedouin]

Agree with the previous poster - the frequency of the transducer only matters to the depth instrument itself - not to anything else. So if you are not changing the instrument but just displaying the data it has output by NMEA then it is not an issue

It could be an issue if you were wanting to replace the depth instrument itself and keep the transducer - but it does not sound as if that is what you are talking about

BTW those i70s really look pretty - I am tempted ....

 

[rob2]

The only situation I can think of that makes the transducer frequency an issue is if you have one embedded in the forefoot of the boat and would like to continue using it. It used to be quite common to glass one in to avoid disturbance from the keel and the floors were impossible to fit to in the preferred location. If your fitting all the new kit as supplied, then no problem.

Rob.