1 vhf antenna and 2 ais

[marcot]

any drawbacks sharing 1 ais antenna with 2 ais receivers? on board an old Ray seatalk E120 and comar ais (inside the boat), outside an AIs 700 + axiom 12. ais 700 has a built-in splitter. can i use this antenna splitter to feed the old ais comar?

 

[Alex_Blackwood]

any drawbacks sharing 1 ais antenna with 2 ais receivers? on board an old Ray seatalk E120 and comar ais (inside the boat), outside an AIs 700 + axiom 12. ais 700 has a built-in splitter. can i use this antenna splitter to feed the old ais comar?

Should be OK if Receive only. No if either transmits!

 

[marcot]

Should be OK if Receive only. No if either transmits!

Thanks. AIS 700 is a transmitter too

 

[Refueler]

I've been pondering this since you posted .. and you last has answered a query I had ... why the splitter.

RX only AIS doesn't care as long as its not paired with a TX;g unit - then a splitter that divides and separates is required.

Given that your splitter is probably designed with VHF and AIS in mind ... and is most likely ACTIVE Splitter ... this means that when one transmits - all others are diconnected. But when not TX'g - both can RX ok ...

I would think that you should be ok ... as the splitter should cut off the other AIS when the 700 transmits. But there we have a question ... the TX'g is frequent and may be such that the other AIS has trouble RX'g targets ??

I reckon go for it - but make sure Splitter is used ... to prevent TX being fed to the other RX AIS.

 

[rogerthebodger]

I am from the school of one tool for each job so I have a separate Arial fro each of ny 2 VHF radios and third for my AIS receiver

This also gives me redundancy should any Arials fail or my mast come down.

I have one on my main mast and one each side of my taga/goal posts

 

[john_morris_uk]

The question I am asking is ‘Why two active AIS units’? Other vessels AIS would find it very confusing getting packets of data with essentially identical information. What possible advantage is there in having two AIS systems?

If the one is rx only surely it will spend all its time with the alarm going saying you’re dangerously close to another vessel which is in fact you.

 

[Buck Turgidson]

The question I am asking is ‘Why two active AIS units’? Other vessels AIS would find it very confusing getting packets of data with essentially identical information. What possible advantage is there in having two AIS systems?

If the one is rx only surely it will spend all its time with the alarm going saying you’re dangerously close to another vessel which is in fact you.

Nah. You insert MMSI in both so they both know who you are. But I think he has one RX and one TX/RX with built in splitter so there is no problem with connecting the RX only to it if that is the easiest way to get AIS downstairs. If the comar is TX/RX then he should probably use network data rather than running both at the same time.
He hasn't mentioned his VHF com radio.
I have to assume it has its own antenna.
I would personally use the splitter as designed and run the VHF com through that leaving the AIS antenna for the old Comar.

But a lot of that is guesswork about the OPs setup.

 

[Alex_Blackwood]

Nah. You insert MMSI in both so they both know who you are. But I think he has one RX and one TX/RX with built in splitter so there is no problem with connecting the RX only to it if that is the easiest way to get AIS downstairs. If the comar is TX/RX then he should probably use network data rather than running both at the same time.
He hasn't mentioned his VHF com radio.
I have to assume it has its own antenna.
I would personally use the splitter as designed and run the VHF com through that leaving the AIS antenna for the old Comar.

But a lot of that is guesswork about the OPs setup.

Missing info again! I am starting to get a thing about posters asking for help with half a story.

 

[john_morris_uk]

Nah. You insert MMSI in both so they both know who you are. But I think he has one RX and one TX/RX with built in splitter so there is no problem with connecting the RX only to it if that is the easiest way to get AIS downstairs. If the comar is TX/RX then he should probably use network data rather than running both at the same time.
He hasn't mentioned his VHF com radio.
I have to assume it has its own antenna.
I would personally use the splitter as designed and run the VHF com through that leaving the AIS antenna for the old Comar.

But a lot of that is guesswork about the OPs setup.

Agreed. Use the splitter for VHF & active AIS. Use network data to share info to other locations on the boat. Simples. It’s also gusty to work and no strange spurious readings or problems.

 

[marcot]

vhf has its own aerial
so: AIS 700 +vhf to one aerial (splitter is included in ais 700)

comar ais to the 2nd aerial.
thanks.