Standard Horizon GX6500: a loaded VHF radio also integrated with Class B AIS

... written for Panbo by Ben Ellison and posted on Oct 11, 2016


The wait is almost over. The Standard Horizon Quantum GX6500 combines Class B AIS and VHF transceivers into one device, an important first in critical marine communications that some boaters have long hoped for. It is not yet for sale pending FCC approval, but the expected price of $800 seems quite reasonable given the install efficiency, the integrated GPS/VHF/AIS features, and a lot more that Standard has designed in. The GX6500 would be an extraordinary radio even without the AIS...

Standard_Horizon_Quantum_GX6500_VHF_radio_and_Class_B_AIS_closeup_aPanbo.jpgI briefly got my fingers on a prototype GX6500 at the NMEA Conference, and the interface to its many features seemed completely up to the task. I don't have dimensions yet, but that's a huge display, and note both the soft key row and the up/down, left/right key column for getting around the menu systems, which are often usefully graphic, plus the knobs for common adjustments.

So that interface accesses an "advanced 80 dB commercial grade" Class D VHF as well as a full Class B AIS with its own target display and CPA/TCPA alarm system. Plus, since it has its own GPS, it can also display COG/SOG and manage waypoints. But here's what else: a dual zone 25W PA / hailer with programmed fog signals and listen back, a voice recorder able to play back two minutes of receive audio, and two types of voice scrambling. And while all that is available just from the single standalone device...

Standard_Horizon_Quantum_GX6500_VHF_radio_and_Class_B_AIS_backside_cPanbo.jpg...the Quantum GX6500 also offers AIS and DSC info integration with navigation systems over both NMEA 0183 and 2000 and -- holy cow -- up to five wired and wireless full-featured remote mics. The two upper right RAM ports handle all those mics, as will be explained shortly, and the bottom ports go like this: one for the plug-and-play 66 channel WAAS GPS antenna, one as an alternate attachment point for the hand mic (with a 20-foot extension cable available), and the standard N2K port (Standard's first on a VHF, but probably just the beginning).

But, yes, the GX6500 does require two antennas, one for the VHF and one for the AIS (preferably an AIS specific model, though a regular VHF stick will work). In other words, it does not contain an internal splitter, which does make installation more difficult and expensive, but it is also arguably the high-performance pro way to go. In fact, the dual antenna requirement also applies to the AIS-receive-only GX6000 model, which will have all the other features of the 6500 and will cost $500 once it's been FCC approved.

Standard_Horizon_SCU-31_GPS_n_SCU-30_wireless_access_point_aPanbo.jpgAt left above is Standard's new SCU-31 GPS Smart Antenna, which is included with the GX6500 but will also be available as a $120 option for the GX6000, thus making it a standalone DSC VHF and AIS plotter if and when you want it to be. To the right is the SCU-30 Wireless Access Point that can connect either new VHF/AIS (via one of its RAM ports) to as many as four RAM4W wireless mics with a range of about 65 feet from the antenna. The RAM4W is shown alongside the RAM4 wired mic below and each of these three optional components will cost $150. It will add up, but a boat could have six Quantum GX stations -- one wired RAM, four wireless, and the base.

However many stations you have, all will have full control of the base, including AIS displays, intercom ability from any one to another or to all, and even an MOB function. The wireless RAM has USB charging to an 1800Ah Li-ion batter purportedly able to provide "up to 14 hours of use", and it not only floats but has the water-activated emergency strobe light seen on Standard's recent handhelds. It even has programmable hot keys for, say, quick access to that intercom function.

So did Standard Horizon leave anything out? The only missing feature I can think of is the numeric keyboard that some pros like, but with either the GX6000 or 6500 you won't have to key in an MMSI to direct call an AIS target. And the 6500 will only have to be set up once with its own MMSI to have both DSC VHF and AIS, either standalone with a single efficient power source (like perhaps when anchored) or data integrated with your underway nav electronics.

This is a first glimpse, and further detail on these new products isn't online yet, but I tentatively applaud Standard Horizon for designing a terrifically full-featured and flexible VHF/AIS combination system at fair prices. I can particularly picture the GX6500 as a valuable communications and safety tool on vessels both small and large. Now what do you all think?


PS: Here's a dimensional drawing of the new radios:



Did they leave anything out? Yes the internal antenna splitter. Would be great if there were two antenna connections with the option of using one with an internal splitter.

I hope this is the first of many, seems odd to me that all VHF-AIS combinations so far have been RX only for AIS.

Posted by: Hugh Saunders at October 11, 2016 12:08 PM | Reply

Hugh, I think it's quite hard to build a VHF / Class B AIS combo device that meets two separate and rigid specifications. It may not even be legal to build one with an antenna splitter inside. I don't believe it's possible, for instance, to receive AIS signals if you are transmitting through the same antenna at 25 Watts.

Standard Horizon was already first to combine a fixed VHF with an AIS receiver, but that's a significantly different animal because AIS receivers are not regulated. There are many such combos available now and all use a single VHF antenna, so I'd call the GX6000 the high performance version of VHF / RX only AIS designs.

Posted by: Ben in reply to Hugh Saunders at October 11, 2016 12:22 PM | Reply

I like wireless mics. I wish EVERY VHF manufacturer offered this feature.

Thus far I am only aware of the Garmin VHF 300 and now this Standard Horizon model.

Posted by: Anonymous at October 11, 2016 12:43 PM | Reply

I wish this had come out a couple of months ago as it might have saved me $600 for a Class B AIS transponder! Great that someone has finally cracked this barrier as it should significantly increase the number of AIS equipped boats through a simpler, cheaper installation.

I wonder about Ben's comment on antenna splitters. I have a Digital Yacht AIT2000 transponder and their SPL2000 splitter, which I use to share a single VHF antenna with a Standard Horizon GX5500S. I have never noticed any disruption in the AIS when transmitting on the VHF. Probably the data transmission and receiving intervals on the Class B AIS are such that they can use a relay to isolate the VHF during the typical relatively brief VHF transmissions without creating any visible impact.

Posted by: Quitsa at October 11, 2016 2:39 PM | Reply

The Simrad/B&G radios have use wireless handsets for years.

Posted by: Anonymous in reply to Anonymous at October 11, 2016 2:44 PM | Reply

Sounds pretty complete, is there a "Stealth" mode for the AIS Xmit?

For those of us who race inshore it's a nice feature to be able to selectively turn off, without having to shut off the receive. With a separate AIS Xceiver, worst case can shut it down, and use the integrated AIS receiver in a VHF.

Using an external splitter should be no issue, just need some low loss short cables to plumb it all together, and you get AM/FM for entertainment on the side.

Regarding wireless microphones, Navico has the H50 for B&G (Simrad has same with different model#)

Handy to have at the helm, or in your pocket as you attend to tasks away from the radio's installation and still retain the 25 Watts and 50' antenna.

Posted by: Sheldon Haynie at October 11, 2016 2:48 PM | Reply

Looks very slick. I wonder if they will sell headsets or even better, in-ears.

We had a Eartec Simultalks for anchor/docking duty but after about two years the audio jack on one of them broke and as the units are sealed we haven't yet found a shop willing to crack ours open and fix it. I am certainly not buying another pricy unit!

So, we end up using our two B&G H50 wireless handsets on intercom mode. The downside is that the headset jack is so absolutely non-standard, the Navico 1-800 guys did not even know it was there, and it took another thread on this website for a reader to post the mic wiring schema. In any event, it seems one would only get Rx, not Tx, so, custom work for scanty return. I just know one of these days I'm going to drop an H50 in the water as I am doing anchor work.

Prospective GX6500 wireless mic buyers should inquire about potential software upgrades. Our B&G wireless mics cannot be updated by the user and must instead be sent to Navico or a specialised dealer —and you can't update the base radio unless you update the mics. We did this already once this year and a couple of months later B&G put out another update that requires again sending the mics to Navico.... hopefully Standard Horizon has a better strategy!

Posted by: Xavier Itzmann at October 11, 2016 3:36 PM | Reply

I have been using a Simrad VHF for 2 years with NMEA2000 and AIS Receive. It also has wireless mike. Another option very affordable.

Posted by: John Miller, Dulcinea at October 12, 2016 9:52 AM | Reply

I dont agree that the trend for combining different functions into one is the right solution. Let us not forget that a failure on a combined VHF and AIS will render both useless.Also the price estimated is not that economic if we look at seperate units. You can purchase a good quality fixed VHF for around the 250 USD and Class B AIS for 500-600. Installation time will be reduced with a combined set. We must consider vessel specifics i.e. I do see a combined unit favored on a Super Yacht Tender, or as a backup second or third station.

Posted by: mvmsystem at October 12, 2016 2:32 PM | Reply

Sheldon, the GX6500 does have Silent Mode, which is the term for turning off TX while retaining RX and may be part of the Class B spec.

I'm still long testing the RS35 VHF & HS35 wireless handset on Gizmo -- used them today -- and while some users had issues with the radio, I think they were eventually fixed with updates and I remain a fan of the handset particularly:

But I think this new SH Quantum is at a different level. MVMsytem, I won't argue about the possible value of independent devices, but I challenge you to show us a VHF of this quality and feature set for $250.

Posted by: Ben at October 12, 2016 8:45 PM | Reply

I am optimistic the combined unit is going to offer a far more reliable red rescue 21 emergrncy button function during the life of a boat than the individual parts integrated together.

To know that if you fall in the water or are very sick your crew can push the button to xmit location to summon help, is a valuable 1st line safety opportunity to get local help heading your way.

Posted by: Dan Corcoran (b393capt) at October 12, 2016 9:04 PM | Reply

Here are the dimensions of the GX6500 and 6000 base units:

OVERALL: 6.9” wide x 4.3” high x 7.6” deep (overall depth includes the front knobs)

CUT OUT: 6.1” wide x 3.6” high x 5.8” deep

I also just posted a dimensional drawing at the end of the entry, and according to a dealer/poster at The Hull Truth, this all means that the radios have "the exact same footprint of the ICOM 504 / 506":

Speaking of ICOM, most of their DSC radios are shipping again in the USA, after being fixed to correct some fairly minor software issues as demanded by the FCC. However, the 604 VHF and the 802 SSB can not fixed and will not be offered again in the US, replacements coming. More detail in the comments here:

Posted by: Ben at October 13, 2016 9:37 AM | Reply

FWIW this setup is 100% legal in Europe / Germany: Icom 506 via active splitter built into a Class B transponder to share one antenna. All modes possible TX off etc.

Posted by: jan at October 13, 2016 2:06 PM | Reply

Thanks, Jan. The Garmin AIS 600 Class B AIS also has a built-in "active" antenna splitter and is FCC approved, but I'm thinking that the FCC might not like to see that inside a VHF.

But regardless of the regulations, don't you think that having a dedicated antenna for each task is ideal when possible? Am I not correct that a single VHF antenna can not receive anything when it's being used to transmit VHF (though most of us don't actually key the transmit button very much)?

Posted by: Ben in reply to jan at October 13, 2016 7:32 PM | Reply

Thanks and agreed, Ben.
The setup I mentioned is installed on a 30ft classic sailing boat...if space and "visual tech-clutter " is no issue I'd also vote for 100% redundant setups, three antennas in best case, two mounted VHF's and one AIS ore two internal AIS transponders, external GPS... etc...and Class A AIS in best case... BTW really liked the discussions on here about A vs B.
Class B protocol means for AIS TX to wait anyway until there's no Class A traffic on the channel...and there are also delays with AIS RX when VHF is in TX, absolutely.

School of thought with the unit in discussion is to put several eggs into one basket, so I'd also want internal splitter when going down that route.
Two VHF's come in handy anyway, so how about two of those combo's with splitter...and two antennas instead of four :-)

If FCC begs to differ between splitter in AIS B transponders vs splitter in VHF AIS combos, would be nice to hear why, me a s dummy enduser can't see much difference.

As a sidenote,
we also opted to add independant IOCM 91 to the setup on said classic boat, RX /TX is much better than expected from a handheld,
we also have an adapter to use better external mobile antennas on the 91.

Good to have those AIS / VHF tranceivers popping up, I'm looking forward for more choices.


Posted by: Jan at October 14, 2016 4:00 AM | Reply

Thanks for another great article Ben,
This gives me a chance to ask why Furuno VHF radios receive so little attention. Seems like their FM-4721 model builds on Furuno's reputation of solid long term investments, yet you can't find any reviews and hardly more than a brochure describing features. For those of us who don't need/want a VHF with AIS, and given that iCom's top end M604A is dead, the FM-4721 seems to bring a feature rich radio. Good alternative?

Posted by: Bo Collier at October 15, 2016 9:24 AM | Reply

Bo, I don't believe the Furuno 4721 is available in the USA. Furuno only sells an IMO compliant VHF radio in the United States which has an MSRP of $2500. The Furuno FM8900S is the only VHF radio shown on the US website

Posted by: Howard in reply to Bo Collier at October 15, 2016 11:29 AM | Reply

Thanks Howard, I guess that explains why you can't find any resellers. But the 4721 is in their 2016 catalog without any mention of not available in the US. I appreciate the info.

Posted by: Bo Collier at October 15, 2016 1:10 PM | Reply

"I don't believe it's possible, for instance, to receive AIS signals if you are transmitting through the same antenna at 25 Watts."

Pretty sure it's possible, seeing as my Standard Horizon GX2200 does it.

Posted by: Robert Carpenter Shook in reply to Ben at October 17, 2016 4:52 PM | Reply

It's likely your setup alternates use of a common antenna, it's less likely that you are concurrently transmitting at 25 watts and sending/receiving AIS.

Posted by: Sheldon Haynie at October 17, 2016 5:03 PM | Reply

Robert, the only way you could tell for sure is to hold down the transmit button on the GX2200 -- or any other VHF sharing an antenna with AIS RX -- for quite a long time. AIS target displays are quite generous about data reception largely because Class B only transmits every 30 seconds at best. It seems to vary from display to display but I think that AIS targets often linger for several minutes after last data reception before the display marks them as invalid or just erases them.

At any rate, I just don't think that a coax cable and VHF antenna can receive anything while 25 Watts of transmission are going the other way.

Posted by: Ben at October 17, 2016 5:55 PM | Reply

Antennas can be used to simultaneously transmit and receive however a complicated and expensive filter called a duplexer must be used. There may also be a digital way of time sharing the transmit and receive information but I believe both of these technologies are beyond the expense of a recreational marine radio. So part of the information will be sometimes missed unless a two antenna system is used. I haven't read through the entire thread but I don't believe that a shared antenna would be preferred in a high density (lots of transmissions) area.

Posted by: Florida Marine Surveyor - Latitude Marine Inc. at October 17, 2016 6:19 PM | Reply

The manual for my Digital Yacht splitter specifically notes "It is not possible for both connected devices to transmit simultaneously using a single VHF antenna. Whilst you are talking on your VHF Radiotelephone no AIS position reports will be transmitted." The manual also makes clear that the antenna is shared unless the VHF or AIS is transmitting, in which case it is switched exclusively to that unit. So both can receive simultaneously but if one transmits, the other is temporarily disconnected from the antenna and can neither receive nor transmit.

Posted by: Quitsa at October 18, 2016 1:34 PM | Reply

Thanks, Quitsa. I haven't noticed it myself, but some boaters using antenna splitters say they can hear a little click when they're listening to something on VHF and the AIS cuts in for a few nano seconds to make a transmission.

So while using a single antenna for VHF and AIS is a bit of a compromise, I don't see any technical compromise to combining AIS and VHF transceivers like the GX6500 does.

Posted by: Ben at October 18, 2016 5:56 PM | Reply

My concern, albeit mild one is when using one of those transmit antenna combiners is that the radios are not coordinated. Both theoretically can transmit at one time, but one is not connected to the antenna.

The radio that is temporarily not connected to the antenna is transmitting into? Is it a 50ohm load that dissipates the RF energy? Or is just an electrical short/open?

Anybody open one up?

Posted by: Howard in reply to Ben at October 18, 2016 6:07 PM | Reply

Howard, I've been long testing a Vesper Marine VHF/AIS/FM splitter for years and have yet to see any problems. In fact, I A/B tested it and could not see any difference in the number or range of targets received (another worry being signal loss):

I believe that the main job of such "active" splitters is to protect each transceiver from RF damage.

Posted by: Ben in reply to Howard at October 18, 2016 7:33 PM | Reply

My experience with the Digital Yacht SPL-2000 is the same. One reason I am not especially concerned with the small interruptions is that I have two VHFs and two antennas. The AIS shares an antenna with my backup VHF. Thus normally I am transmitting on VHF from the radio that has a dedicated antenna and the AIS transponder is not affected whether receiving or transmitting. I have done an "A/B" test with my two VHF radios using a shore "test" station and the one with the splitter seems to have just as much range as the one with its own antenna. I think this is a good setup for people who are not going for the Gizmo antenna forest look and have two VHFs on board.

In my case the splitter allows me to have two antennas instead of three and the AIS benefits from being connected to a 17' antenna mounted on the hardtop, which gives it pretty incredible range for Class A transponders on large ships. I regularly see AIS targets on my plotter that are 35-40+ miles away (not that it matters much to have that range). Other people with similar antenna height have reported that they picked up my AIS over 12 miles away, which has to be about as good as Class B can achieve.

Posted by: Quitsa at October 19, 2016 2:12 AM | Reply

The ORC class rules specify, and I quote:

3.29.13 an AIS Transponder which either:
a) shares the masthead VHF antenna via a low loss AIS antenna splitter; or
b) has a dedicated AIS antenna not less than 38 cm (15”) in length mounted with
its base not less than 3 m (10’) above the Waterline and co-axial feeder cable
with not more than 40% power loss (Loss Estimator)

My AIS range went up considerably when I moved from the dedicated AIS antenna (at about 4 m above sea level) to a shared masthead antenna (at 29 m), both in how far away I am seen and how far I can see myself.

Posted by: Kees at October 19, 2016 8:42 AM | Reply

Ben, I agree - it is not possible for the AIS receiver to hear anything while the 25w VHF transmitter is on when using the same antenna - without large & complex duplexing filters, anyway. But it is also true that unless your VHF and AIS antennas are separated by a large distance (more distance than is available on most cruising boats IMHO), the AIS receive performance will be degraded when you are transmitting on the main VHF anyway.
I'd be quite surprised if the various "splitters" didn't terminate the AIS into a dummy load when the main VHF is transmitting - it would be easy to do, and the amount of power being dissipated is trivial. The 30 millisecond dropout experienced by the main VHF receiver when the AIS transmits would be barely audible. I've occasionally heard a "pop" while receiving (I use a separate AIS antenna) that I attribute to the AIS transmitting and desensing the receiver - but it is very subtle.

The dimensions given for the GX6000/6500 are quite close to the IC-506 - EXCEPT the depth, which is 4.09 inches for the Icom. As you know, I have my helm VHF in a console box, so depth is a big concern for me. I have been unhappy with the receiver performance of the GX1600 I have, and I've been looking at alternates.

Posted by: Hartley in reply to Ben at October 22, 2016 10:26 AM | Reply

Yo, Bo! I understand that the Furuno FM-4721 is built by Standard Horizon and quite a bit like the GX5500:

Posted by: Ben in reply to Bo Collier at October 26, 2016 4:51 PM | Reply

Thanks Ben,
Wow, the SH GX5500 is the Furuno FM-4712 with the keypad and display flipped. I guess when you look at who makes Standard Horizon it makes sense. Maybe I'm old fashioned but I prefer a VHF with a keypad and about the only thing other than the channel number I want cluttering my display is GPS position. Looks like the GX5500 has been around since about 2009 but I'm going to pull the trigger and buy two for our newly redesigned helm and try and sell the one iCom 604A (still in the box) since a second matching one is no longer available. ICom may have really shot themselves in the foot by not being able to resolve their M604A FCC issue.
Once again, thanks for sharing your vast knowledge.

Posted by: Anonymous in reply to Ben at October 28, 2016 9:05 AM | Reply

I would not hesitate to get a GX5500 having used one for five years. It has excellent performance and if you don't need new the features in the GX6500, should work just fine. I put one in my new boat a couple of months ago in fact.

I would bet the basic VHF circuits are not really much changed -- specifications are identical.

Posted by: Quitsa in reply to Anonymous at October 29, 2016 4:18 AM | Reply

GX6500 looks very interesting. I have to replace a AIS transceiver and VHF after a lightning strike. Any ideas how long the FCC approval might take?

Posted by: Cmonster at October 31, 2016 6:10 PM | Reply

The filtering required to have one port / one antenna would be large, and potentially need periodic adjustments to keep it in tune. I'd fear a good knock from a storm could get the filter out of tune.

A two way radio shop could add the filters necessary to accomplish this. Size would depend which VHF channels you want to keep. Channel 16 is > 5 MHz separation from AIS frequencies. An $80 duplexer from China via ebay will give you that separation. They're about the same size as the radio itself, maybe a bit smaller. Channel 88 is only 4.5 MHz which becomes more difficult. 84, 85, and 86 are duplex, and will be very difficult. Now we're talking about a diplexor that is not practical. Probably the size of 6 medium size fenders for a 30' boat.

Posted by: k8md at November 5, 2016 9:02 AM | Reply

Love it! Finally everything I want in one package.

Posted by: Singularity at November 5, 2016 5:13 PM | Reply

Besides the missing internal antenna splitter, I am disappointed to see they opted for a smart GPS antenna instead of a coax fed antenna, like nearly everyone else. The advantage of a coax fed antenna is we have a variety of antennas to choose from to suit the vessel, we can easily cut the cable to length and in the case where we have multiple coax fed GPS devices, we can share the antenna signal and reduce our antenna count.

I look forward to a less feature rich version (e.g. no hailer) and a smaller and lighter package, just 'cuz it will fit our clients better.

Any idea of standby current consumption?

Posted by: emsusa at November 7, 2016 11:32 AM | Reply

How soon? I do not see any FCC application pending for this radio.

Posted by: Waterman at November 12, 2016 4:58 PM | Reply

From a reliable source on Nov 6th:

"Thank you for contacting Standard Horizon, the GX6500/6000 is still pending FCC approval. We hope to begin shipping in late December."

Posted by: Singularity at November 16, 2016 10:32 PM | Reply

Very interesting, indeed. I'm the happy owner of not only a SH GX2200 (receive-only AIS), but I even bought the loudhailer and the remote mic (it's in a pilothouse with an outside helm). I'm not sure if I would go for this right away, but I'm hoping it will lower the price of Vesper and Digital Yacht's similar transceivers, because it certainly hits a sweet spot for those wanting both to be see and be seen via both radar and AIS.

Posted by: Marc Dacey at November 20, 2016 11:26 PM | Reply

Remember, Furuno's small boat VHFs are typically manufactured by a subcontractor. The 3724 is actually a Vertex/Standard radio.

Posted by: Anonymous in reply to Bo Collier at December 14, 2016 9:16 AM | Reply

Icom UK has announced a new M605EURO model that has many of the high end features SH designed into the (AIS rx only) GX6000, plus a beautiful color screen:

Posted by: Ben at December 22, 2016 10:29 AM | Reply

Did they leave anything out? Unless I missed it - WIFI to connect AIS to Tablet Plotter Apps

Posted by: Monty at January 7, 2017 6:44 AM | Reply

Now showing in their 2017 catalog. Interesting that they label it commercial

Posted by: Howard at January 16, 2017 11:30 PM | Reply

I really wish it operated with one antenna as well.

We have the matrix now with ais receive only, with the antenna on the masthead with low loss cable up the mast. Receives big ships out to 70 miles. How are the antenna ports set up? Is one port vhf tx and receive? And the other port is ais rx and tx?

In my situation, it would be ideal to use it like the matrix, using the masthead antenna for vhf/ais receive. And the second port for ais tx on a deck mounted antenna.

But would bet the radio is set up as 1 port vhf other port ais.

Posted by: Louie at February 2, 2017 10:02 AM | Reply

Putting an AIS on the stern rail is a good option. You can use an antenna better tuned to AIS, the install is usually a DIY cable run (use a deck gland), and although you lose range vs masthead the range is still good with the taller commerical vessels.

Posted by: Dan Corcoran (b393capt) at February 3, 2017 1:36 PM | Reply

Reading this and not finding any more specific info else ware on the Internet i wonder about why it is called "commercial grade" and class D. I would think a commercial grade would be an class A gmdss vhf. Then it would also dictate 2 antennas anyway as a "class A" vhf uses the one for listening on DSC channel 70. Modern receivers can easily listen on several freq simultaneously, and similar can signal be modulated on several freq before it is amplified so maybe the one receives and the other transmits for both functions (AIS and VHF). Placing 2 antennas inline vertically also give less interference. Anyone have a pointer to a manual or more specific data ?

Posted by: Johan at February 24, 2017 8:20 PM | Reply

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