GPS NMEA 0183 Output to more than one Device

pjf

Member
Joined
24 Oct 2005
Messages
43
Visit site
Hi,

Quick question; is it possible to supply GPS data from a single GPS receiver to 2 or more different instruments. i.e and AIS display and VHF radio?

If so, how best to do it practically?

Thanks
 

David2452

Active member
Joined
6 Jun 2001
Messages
3,955
Location
London & Fambridge
Visit site
0183 is single talker multiple listener so yes it is normal within limitations, just use a junction box or even "Y" the leads. Don't try putting two inputs though unless the reciever is multi chanel 0183.
 

Danbury

New member
Joined
17 May 2013
Messages
599
Location
Southsea
Visit site
Interesting thread... I tried adding a 3rd a few months ago, but it didn't work. I assumed it was because I had too many (it worked fine with any two). Is there no 'REN' type loading count like you get with telephone lines ?
 

andyp

Member
Joined
22 Oct 2009
Messages
88
Location
Gosport
Visit site
Most reckon that one NMEA 'talker' can feed no more than four 'listener' devices.

Your difficulty adding a third device may relate to differing earth/return arrangements. Some are +ve and-ve while others work on signal and ground connections.

If you need to supply more devices then a multiplexer (costly) or one of Angus' YAPPs will be needed.
 

David2452

Active member
Joined
6 Jun 2001
Messages
3,955
Location
London & Fambridge
Visit site
Just checked my NMEA 0400 standards manual and it states a maximum of three before a signal expander device is required, I had it in my head that it was more, I so rarely use 0183 nowadays that I had forgotten.
 

ditchcrawler

Well-known member
Joined
7 Oct 2001
Messages
1,717
Location
River Orwell,East Coast
Visit site
I feed four devices(Yeoman,VesperAIS,GPS repeater and Standard Horizon 2100 radio from my Garmin 128.Garmin said four should be OK especially as the feed to a repeater is very low.I also have a feed to my radar but that is not on very often but when it is on they all seem to work.
 

bedouin

Well-known member
Joined
16 May 2001
Messages
32,592
Visit site
Yes - many people connect multiple listeners to one talker with no issues but it is not guaranteed to work. You are in effect connecting the input circuits of all listeners in parallel and it is possible that that will cause interference between them.

Also it may make a difference (either way) if the devices are switched on or not
 

David2452

Active member
Joined
6 Jun 2001
Messages
3,955
Location
London & Fambridge
Visit site
I feed four devices(Yeoman,VesperAIS,GPS repeater and Standard Horizon 2100 radio from my Garmin 128.Garmin said four should be OK especially as the feed to a repeater is very low.I also have a feed to my radar but that is not on very often but when it is on they all seem to work.

That is not unusual, the standards are what will work constantly and accurately, outside that may work but may not work all of the time and will also depend more on the quality of the install and shielding etc.
 
Top