Icom iM604A User manual

Practical Sailor Review
“Feature Loaded High-end VHFs”
by Frank Lanier
iM604A
HF Marine Transceiver
©2012 Icom America Inc. The Icom logo is a registered trademark of Icom Inc. 41303
Testers put seven top-of-the-line VHFs through bench test-
ing to determine which ones offer the most value for sailors.
Icom’s M604A’s many features are reviewed and analyzed.
www.practical-sailor.com

july 2012 7practical sailor
The high-end,xed-mount marine
VHF radios that Practical Sailor
recently tested go way beyond the
basic capabilities oered by many of
the moderately priced VHF units in
our June 2012 review. Standard fea-
tures for this group include integral
high-wattage hailers, multiple remote
microphone connections, and the ca-
pability to store more Maritime Mo-
bile Service Identity (MMSI) numbers
and inbound Digital Selective Calling
(DSC) data. Bonus capabilities in these
top-of-the-line radios include the abil-
ity to act as part of an intercom system,
to display vast amounts of navigation
data, and to produce automated fog
signals at the touch of a button. (See
"Features 411" for a glossary of features
and functions.)
Taking advantage of all the features
found in these top-of-the-line units
often requires purchasing additional
equipment—navigation data must be
supplied by a compatible, onboard
GPS/chartplotter; external horns must
be installed to use hailer and foghorn
options; and so on. e radio itself ends
up being the base for building a com-
munications system, and buyers could
spend hundreds more to fully capitalize
on the capabilities of one of these multi-
function marine VHF radios.
Sailors who rarely use the bells-and-
whistles may be better served with one
of the mid-priced radios we reviewed
in the June article, and bluewater cruis-
ers might want to consider buying two
budget-friendly VHFs (one to wire to
a mast-top antenna and the other to
a stern-rail antenna) to add redun-
dancy and a layer of security for about
the same price as one of the high-end
VHFs. However, if you’re in the market
for a primary VHF and have the budget
for the added features, you will be well
served with one of the seven following
high-end radios.
What We tested
During our last look at high-end VHFs
(PS, October 2009), the Standard Hori-
zon GX5500S took Best Choice honors
andthe company’s GX5000S was named
Budget Buy. For our 2012 evaluation, we
tested seven xed marine VHFs priced
above $300. Testers evaluated one radio
from industry leader Standard Horizon,
theMatrixAIS+GX2150, and two(VHF
200 and VHF 300) from Garmin, a
worldwide provider of navigation, com-
munication, and information devices.
Icom, a global manufacturer of marine
and avionics communications products,
provided three units for our test: the IC-
M424, IC-M504A, and IC-M604A. We
also tested the Ray 218 from Raymarine,
a world leader in marine electronics for
recreational boating.
All of the units in our test group are
NMEA 0183 network compatible, and
the two Garmin radios are also NMEA
2000 compatible. Each of the test prod-
ucts also featured microphones with
various control options (from channel
changing to channel scanning); some
featured removable primary mics,
which can be handy when troubleshoot-
Testers put seven top-of-the-line VHFs through bench testing to determine which ones oer the most value for sailors.
Feature Loaded High-end VHFs
Fixed marine radios priced at $300-plus oer plenty of extras.
Photos by Frank Lanier

8july 2012 www.practical-sailor.com
VALUE gUidE high-End fixEd Vhf rAdios
MAKER garmin icom raymarine standard horizon
MODEL VHF 200 VHF 300 w/GHS
remote handset IC-M424 IC-M504A IC-M604A Ray 218 Matrix AIS +
GX2150 $
PRICE $310 $546 $330 $331 $512 $456 $340
WARRANTY
2 years limited
(Americas,
Caribbean)
2 years limited
(Americas,
Caribbean)
3 years 3 years 3 years 3 years limited 3 years
NMEA COMPATIBILITY NMEA 0183 & 2000 NMEA 0183 & 2000 NMEA 0183 NMEA 0183 NMEA 0183 NMEA 0183 NMEA 0183
MIC CONTROLS* 1,2,3 1,2,3,4,5,6,7 1,2,6 1,2,6 1,2,6 1,2,3,6,7 1,2,3
REMOTE MIC CAPABLE Yes (3 total) Yes Yes Yes Yes (2 total) Yes Yes
FOOTPRINT H x W x D 4.65 x 7.56
x 6.42 inches
7.09 x 9.75
x 2.5 inches
3.23 x 6.46
x 4.72 inches
4.33 x 6.5
x 4.27 inches
4.34 x 8.65
x 4.31 inches
3.84 x 7.79
x 7.06 inches
3.1 x 7.1
x 4.8 inches
DISPLAY SIZE H X W 2.75 x 1.6 inch 1.63 x 1
inch (mic) 2.75 x 1.38 inch 2.75 x 1.38 inch 2.75 x 1.38 inch 2 5/8 x 1 3/8 inch 2 7/8 x 1 3/8 inch
SCRAMBLER No No No Yes Yes No Yes
HAILER 25 watts 30 watts 10 watts 25 watts 30 watts 30 watts 30 watts
AUTO FOG Yes Yes No Yes Yes Yes Yes
WATERPROOF IPX7 IPX7 IPX7 IPX8 IPX7 IPX7 IPX7
TEsT rEsULTs TEsT rEsULTs
AUDIO OUTPUT  3 feet97 decibels 83 decibels 88 decibels 84 decibels 97 decibels 89 decibels 88 decibels
TRANSMIT POWER
high/low at 13.8 volts24.8 / 1.0 watts 21.8 / .85 watts 22.2 / .81 watts 22 / .80 watts 22.5 / .81
watts 22.8 / .90 watts 23.5 / .81 watts
TRANSMIT POWER
high/low at 11.8 volts24.2 / 1.0 watts 21.7 / .85 watts 21.5 / .76 watts 21.7 / .80 watts 21 / .80 watts 22.8 / .90 watts 23.2 / .80 watts
POWER DRAW
high/low transmit at 13.8 volts4.5 / 1.2 amps 4.3 / 1.1 amps 3.0 / .4 amps 3.7 / 1.1 amps 3.9 / 1.4
amps 3.4 / .6 amps 3.8 / 1.2 amps
POWER DRAW
high/low transmit at 11.8 volts4.7 / .5 amps 4.6 / .5 amps 3.0 / .3 amps 3.7 / .5 amps 3.5 / .7 amps 3.4 / .6 amps 3.6 / .6 amps
TRANSMITTER FREQUENCY
STABILITY Very good Very good Good Very good Excellent Excellent Excellent
RECEIVE SENSITIVITY Very good Excellent Very good Very good Very good Good Very good
DISPLAY RATING Good Good Good Good Good Good Good
AUDIO QUALITY Very good Good Good Good Excellent Excellent Good
TRANSMIT POWER STABILITY Very good Excellent Excellent Excellent Good Very good Very good
COMMENTS
Position tracking;
detachable mic;
intercom (when
coupled with
GHS 10 mic);
highest power
output and highest
amp draw.
Uses Garmin
GHS handset
for display and
control; lowest
power output
and lowest
audio output;
best receiver
sensitivity.
Lowest power
draw, but worst
frequency error
of group (still
within specs).
AquaQuake
speaker draining
feature, intercom
(when coupled
with optional
Command Mic); rear
mic connection;
front panel mic
not detachable.
AquaQuake;
intercom
(when coupled
with Command
Mic); mic
detachable;
only one with
keypad.
Receiver
sensitivity was
lowest of group
but was good and
within specs.
Only unit with
built-in AIS; least
frequency error.
Best Choice $Budget Buy Recommended
* Mic controls: 1= Push to talk, 2= Channel change, 3= Quick 16/9, 4= Distress key, 5= Volume adjust, 6+ High/Low power, 7=Other
electronics

july 2012 9practical sailor
ing; and all were capable of supporting
remote “smart” mics. A few even sup-
ported multiple remote mics.
All of the radios had channel scan-
ning features, ranging from standard
and custom memory scanning to dual
watch, which monitors channel 16 every
couple of seconds, and tri-watch, which
monitors both 16 and 9. Each radio is
also waterproof to IPX7 (can handle im-
mersion in 3 feet of water for up to 30
minutes) or IPX8 standards (rated for
continuous underwater use), and all can
be interfaced with a GPS.
One test unit, Standard Horizon’s
Matrix GX2150, featured a built-in Au-
tomatic Identication System (AIS) re-
ceiver that displays other boats’ AIS data
(including vessel name, speed, course,
etc.) on a radar-like screen.
Only one test radio, the IC-M604A,
featured an alphanumeric keypad,
which can make entering MMSI con-
tact numbers and DSC call data faster.
According to Icom Sales Manager David
McLain, fewer than 5 percent of recre-
ational boaters use DSC functions, so an
alphanumeric keypad is not always con-
sidered a must-have feature. VHFs with-
out keypads are also typically cheaper
and require less mounting space; how-
ever, access to a keypad is still a valuable
benet, in our opinion.
All of the test radios feature automat-
ic fog signals via a hailer, and all have
Class D DSC capabilities and operation,
which means they have one receiver that
monitors voice channels and another
that continuously monitors channel 70
for digital DSC calls. Also, all DSC Class
D radios will make distress, individual,
all ships, and group calls.
As noted in our June mid-priced
VHF test, GPS compatibility and DSC
capability are imperative for a VHF to
serve its intended function: distress no-
tication. Providing the unit with GPS
data and a properly programmed Mar-
itime Mobile Service Identity number
(MMSI) for DSC operation means the
boat can be more easily identied and
located in an emergency.
To make a distress call with a DSC-
equipped VHF, users simply press the
well-marked, red distress button for ve
seconds. Once the DSC call is acknowl-
edged, users would then issue a voice
Mayday on VHF channel 16.
Future articles will take a look at
other marine communication products
and accessories, including remote VHF
microphones, handheld VHFs, portable
sat phones, and AIS standalone units.
hoW We tested
Practical Sailor testers ran all the radios
through a series of bench tests—includ-
ing transmitter power output, frequency
accuracy and stability, and receiver sen-
sitivity—using our Ramsey COM3010
service monitor. All radios in our test
group met industry standards with re-
gards to the above tests, but some did it
better than others.
Regulations set by the U.S. Federal
Communications Commission (FCC)
restrict the maximum power output of a
marine VHF transmitter to 25 watts and
specify the need for a low-power setting,
typically 1 watt, for harbor use. Testers
took transmitter power measurements
directly off the VHFs’ radio antenna
ports, because in any real-world sce-
nario, factors such as antenna size and
design, connecting cable length and
type, or faulty connections or corrosion
could limit the actual radio frequency
(RF) power emitted from the antenna.
Transmitter power stability was rated
over a range of tests that included vary-
ing the input voltage and radio tempera-
ture. e less variation in power output,
the higher the radio was rated.
Frequency accuracy is the ability of
the transmitter to send out signals on
a selected frequency. Frequency stabil-
ity measures the transmitters’ ability to
maintain frequency accuracy. e FCC
mandates an accuracy of 10 parts per
million (about 1550 Hz o frequency).
Industry groups typically call for half
that error.
Each unit was connected to a regulat-
ed power supply using the factory leads
and appropriate crimp-on terminals.
All manufacturer-supplied power leads
contained a fuse holder and fuse. Power
draw was recorded while transmitting at
13.8 and 11.8 volts DC, in both high and
low power modes.
Receiver sensitivity, the ability of the
radio to hear a weak signal, is normally
electronics
VALUE gUidE high-End fixEd Vhf rAdios
MAKER garmin icom raymarine standard horizon
MODEL VHF 200 VHF 300 w/GHS
remote handset IC-M424 IC-M504A IC-M604A Ray 218 Matrix AIS +
GX2150 $
PRICE $310 $546 $330 $331 $512 $456 $340
WARRANTY
2 years limited
(Americas,
Caribbean)
2 years limited
(Americas,
Caribbean)
3 years 3 years 3 years 3 years limited 3 years
NMEA COMPATIBILITY NMEA 0183 & 2000 NMEA 0183 & 2000 NMEA 0183 NMEA 0183 NMEA 0183 NMEA 0183 NMEA 0183
MIC CONTROLS* 1,2,3 1,2,3,4,5,6,7 1,2,6 1,2,6 1,2,6 1,2,3,6,7 1,2,3
REMOTE MIC CAPABLE Yes (3 total) Yes Yes Yes Yes (2 total) Yes Yes
FOOTPRINT H x W x D 4.65 x 7.56
x 6.42 inches
7.09 x 9.75
x 2.5 inches
3.23 x 6.46
x 4.72 inches
4.33 x 6.5
x 4.27 inches
4.34 x 8.65
x 4.31 inches
3.84 x 7.79
x 7.06 inches
3.1 x 7.1
x 4.8 inches
DISPLAY SIZE H X W 2.75 x 1.6 inch 1.63 x 1
inch (mic) 2.75 x 1.38 inch 2.75 x 1.38 inch 2.75 x 1.38 inch 2 5/8 x 1 3/8 inch 2 7/8 x 1 3/8 inch
SCRAMBLER No No No Yes Yes No Yes
HAILER 25 watts 30 watts 10 watts 25 watts 30 watts 30 watts 30 watts
AUTO FOG Yes Yes No Yes Yes Yes Yes
WATERPROOF IPX7 IPX7 IPX7 IPX8 IPX7 IPX7 IPX7
TEsT rEsULTs TEsT rEsULTs
AUDIO OUTPUT  3 feet97 decibels 83 decibels 88 decibels 84 decibels 97 decibels 89 decibels 88 decibels
TRANSMIT POWER
high/low at 13.8 volts24.8 / 1.0 watts 21.8 / .85 watts 22.2 / .81 watts 22 / .80 watts 22.5 / .81
watts 22.8 / .90 watts 23.5 / .81 watts
TRANSMIT POWER
high/low at 11.8 volts24.2 / 1.0 watts 21.7 / .85 watts 21.5 / .76 watts 21.7 / .80 watts 21 / .80 watts 22.8 / .90 watts 23.2 / .80 watts
POWER DRAW
high/low transmit at 13.8 volts4.5 / 1.2 amps 4.3 / 1.1 amps 3.0 / .4 amps 3.7 / 1.1 amps 3.9 / 1.4
amps 3.4 / .6 amps 3.8 / 1.2 amps
POWER DRAW
high/low transmit at 11.8 volts4.7 / .5 amps 4.6 / .5 amps 3.0 / .3 amps 3.7 / .5 amps 3.5 / .7 amps 3.4 / .6 amps 3.6 / .6 amps
TRANSMITTER FREQUENCY
STABILITY Very good Very good Good Very good Excellent Excellent Excellent
RECEIVE SENSITIVITY Very good Excellent Very good Very good Very good Good Very good
DISPLAY RATING Good Good Good Good Good Good Good
AUDIO QUALITY Very good Good Good Good Excellent Excellent Good
TRANSMIT POWER STABILITY Very good Excellent Excellent Excellent Good Very good Very good
COMMENTS
Position tracking;
detachable mic;
intercom (when
coupled with
GHS 10 mic);
highest power
output and highest
amp draw.
Uses Garmin
GHS handset
for display and
control; lowest
power output
and lowest
audio output;
best receiver
sensitivity.
Lowest power
draw, but worst
frequency error
of group (still
within specs).
AquaQuake
speaker draining
feature, intercom
(when coupled
with optional
Command Mic); rear
mic connection;
front panel mic
not detachable.
AquaQuake;
intercom
(when coupled
with Command
Mic); mic
detachable;
only one with
keypad.
Receiver
sensitivity was
lowest of group
but was good and
within specs.
Only unit with
built-in AIS; least
frequency error.
Best Choice $Budget Buy Recommended
* Mic controls: 1= Push to talk, 2= Channel change, 3= Quick 16/9, 4= Distress key, 5= Volume adjust, 6+ High/Low power, 7=Other

10 july 2012 www.practical-sailor.com
stated in micro-
volts—usually from
0.22 to 0.35 micro-
volts for marine
VHFs, with industry
groups recommend-
ing a minimum of
0.50. Each VHF was
tested for the minimum signal it could
receive at a specic industry standard
setting between background noise and
generated signal. All the radios proved
more than sensitive enough to pick up
weak signals within industry standards.
VHF displays were rated on size and
readability, the quality of information
displayed, and backlighting.
One very important function of the
marine VHF radio is its ability to re-
produce the sounds of incoming voice
communications via internal audio
amplier and speaker. If you can’t hear
the audio, it doesn’t really matter how
well the transmitter or receiver works.
To rate audio systems, testers measured
the sound pressure levels at maximum
volume while inputting a 1-kHz tone.
e measurements were taken from 1
meter away. Testers also monitored a
weather channel at various volume levels
to evaluate overall sound quality.
garmin VhF 200
While very similar to the Garmin VHF
100 unit reviewed during our June
2012 evaluation of mid-level radios, the
VHF 200 brings addi-
tional features to the
table. These include
expanded NMEA
2000 capabilities,
re-locatable speaker
and mic, hailer and
foghorn functions,
and compatibility with Garmin’s GHS
10 or GHS 10i remote microphones.
Front panel controls include three
rotating knobs for channel selection,
volume, and squelch, and the channel
selector also serves as an “enter” key. e
power button does double-duty as the
quick-select key for channel 16/9, high/
low power selection, DSC, menu, and
clear. ree so keys below the display
are linked to onscreen menus and pro-
vide access to functions such as screen
adjustments, navigation data congura-
tion, channel group selection, channel
name editing, etc. Testers found the
menu functions to be well-labeled and
easy to use.
The 200 uses a monochrome dot-
matrix screen to display channel num-
bers, transmitter power level, selected
channel group, and channel com-
ments. Information too
long to display in one
view scrolls across the
bottom of the screen.
e 200 has numer-
ous scanning op-
tions—normal,
saved channels,
dual watch, tri-
watch, etc.—and
also features NOAA weather alerts
and position tracking, which allows a
mariner to locate and keep tabs on up
to three other boats in the area.
e VHF 200, which features a unique
low-prole ush-mount, was rated Very
Good for transmit power stability, fre-
quency stability, and receiver sensitivity.
Audio output was one of the highest of
the group (97 decibels), earning a Very
Good for sound quality. At 24.8 watts
(13.8 vDC), it had the high-
est transmit power output
of our test group, but con-
versely, it also
had the highest
power draw.
Constructed
to IPX7 stan-
dards, the 200 comes with a two-year
limited warranty good in the Americas
and Caribbean.
Bottom line: The Garmin 200 is a
solid radio that covers all the basics, but
it also has the shortest and most limited
warranty.
garmin VhF 300
Unique in our test group, the 300 is es-
sentially a multi-station communica-
tions “black box” that supports up to
three Garmin GHS full-function remote
mics. Operation of the unit is via the pro-
vided GHS 10 mic, which allows full ra-
dio control from a remote location.
e GHS 10 mic features a 2-inch LCD
display. Testers noted that some sight-
challenged sailors might have problems
reading the small screen, which is the
VHF’s only display.
e mic also has a ro-
tary key for frequently
used tasks and three
soft buttons for dy-
namic controls. Audio
is provided by the GHS
10’s built-in speaker
and the 300’s four-inch
active speaker with a vol-
ume knob. A third-party
passive speaker could be added.
The VHF 300 provides full NOAA
weather alerts and DSC capabilities
when interfaced with a compatible GPS
chartplotter (NMEA 0183 or 2000). Its
position-tracking feature allows users
to locate and keep tabs on up to three
other DSC-equipped boats in the area.
The 300 also has a two-way, 30-watt
hailer system.
Two of its most unique features are a
voicemail function that allows users to
record a 15-second voicemail message
that can be delivered to any MMSI num-
ber, and the ability to record and replay
the last 90 seconds of any incoming voice
transmission with the touch of a button.
e 300’s remote-mic setup is a good
space-saving option, and testers liked
electronics
Garmin 200
Features 411
Garmin 300
Most all VHF mics provide remote control features. The GX2150 Matrix AIS+ (#1)
provides just the basics while the Garmin 300 remote mic (#2) can control all radio
functions and has a display. The Raymarine 218 mic (#3) controls a number of the
more common VHF functions, including channel scan.
3
2
1

july 2012 11practical sailor
being able to add
multiple stations.
However, hav-
ing multiple mics
should not be con-
fused with having sys-
tem redundancy since the mics depend
on a single transceiver. e redundancy
provided by a second VHF radio might
be a more prudent approach than relying
only on remote mics for long-distance
cruisers.
Performance-wise, the VHF 300 held
its own. Power and audio output was the
lowest of the test group, but it did have
the best receiver sensitivity. Transmit
power stability was Excellent, while fre-
quency stability was Very Good. Audio
quality was also rated Good.
e 300 carries the same limited two-
year warranty as the Garmin 200.
Bottom line: e 300, the most ex-
pensive VHF in the group, is well-built
and oers a lot of options from both op-
erational and installation standpoints,
but its limited
warranty kept
it out of the
winner’s circle
in this close
evaluation.
icom ic-m424
Icom bills the IC-M424 as the world’s
first fixed-mount VHF with Class D
DSC and active noise canceling, a fea-
ture that our test setup unfortunately
didn’t allow us to try out.
The IC-M424 also features Icom’s
new so-key user interface, which is in-
tuitive, easy to use, and provides quick
access to radio functions with fewer
button pushes than a typical menu-
driven interface. e radio
is compatible with the new
Icom CommandMicIV
(HM-195) microphone,
which shares the
same so-key user
interface.
e IC-M424 has a built-in 10-watt
amplifier that increases audio output
for functions such as the PA and fog-
horn with the addition of an external
speaker. When connected to an external
GPS receiver, it displays time and cur-
rent position. When receiving position
information from another vessel, the IC-
M424 can also transfer it to a compatible
chartplotter.
Other features include priority and
normal scan, dual/tri-watch monitoring
function, and weather channels (with
alert function). When coupled with
an Icom MA-500TR Class B AIS tran-
sponder, the IC-M424 can make calls to
an AIS-equipped target boat using the
transponder with a few button pushes
and without entering the tar-
get’s MMSI number. Users
simply select the AIS target
from the display screen, se-
lect the VHF channel you
want to use, then push
the DSC call button.
Features 411
AquaQuake: A draining function specic to Icom radios; a
vibrating "buzz" clears water from the speaker grill.
Noise-canceling: Reduces background noise, so you can be
heard and can hear more clearly.
PA/hailer and foghorn: Public address function allows
users to make announcements from the mic like a loud
speaker when an optional external speaker is installed. The
foghorn emits horn sounds from the external speaker.
Waterproof ratings: IPX7 means the VHF can handle sub-
mersion to 3 feet deep for up to 30 minutes. An IPX8 rating
means the unit can handle continuous underwater use.
Dual-watch scan: A channel scan mode that monitors chan-
nel 16 and another selected channel every few seconds.
Tri-watch scan: Monitors both channel 16 and two other
selected channels while scanning.
Priority scan: Channel 16 is checked between every other
channel during scan.
Memory scan: All VHF channels in the VHF memory are
scanned from lowest to highest.
Normal scan: VHF channels are scanned in numeric order.
MMSI: Maritime Mobile Service Identity number. Boats are
assigned one nine-digit MMSI for all onboard equipment ca-
pable of transmitting and receiving digital signals—EPIRBs,
AIS devices, DSC-capable VHFs, INMARSAT satellite terminals,
etc.—and that number serves as an identier for the boat.
The boat’s emergency contact info is linked to the MMSI, so
when a distress call is broadcast, the info is included in the
message, giving rescue and emergency personnel accurate
details of the boat.
DSC: Digital Selective Calling; primarily a distress-alerting
function. Users can send a pre-congured digital distress
message (over channel 70) to emergency personnel and oth-
er DSC-equipped boats in their area. The message contains
information about the boat and its owner, its MMSI number,
the nature of the distress, and priority of the call. When a
DSC radio is connected to a GPS, the Mayday includes the
boat’s location. The transmission takes about one-third of a
second and is automatically repeated until a rescue author-
ity answers.
Class D DSC: Class D radios have two separate receivers, one
for voice communications and the second for continuously
monitoring channel 70 for any DSC calls.
A Rundown on Common VHF Features and Functions
Icom IC-M424
Icom IC-M504A

12 july 2012 www.practical-sailor.com
Aer seeing the acknowledgement “Able
to comply” on the 500TR screen, users
key up the VHF and talk.
e IC-M424 performed well over-
all. It had the lowest power draw of the
group and had Good transmit power
stability. Both audio level and quality
were rated Good.
Bottom line: e IC-M424 oers very
good overall performance and a long list
of desirable features. We’d recommend
it as an aordable VHF for those who
already have an AIS or those not seeking
a VHF with built-in AIS.
icom ic-m504a
e IC-M504A is a compact, robustly
constructed radio well suited for the ma-
rine environment. It’s the only radio of
our test group with a waterproof rating
of IPX8 (continual submersion in con-
ditions identied by the maker). It per-
formed well compared to the other test
radios, garnering an Excellent for trans-
mit power stability and a Very Good for
receiver sensitivity and frequency error.
e MM504A can connect to one re-
mote mic and can operate as part of an
intercom system. When interfaced with
a compatible GPS, it will display time
and position data, boat course, and boat
speed. Like all DSC Class
D radios, it will make
distress, individual, all
ships, and group calls.
Own ship and other ship
position data can also be
exchanged easily us-
ing the position re-
quest or position report functions. e
received position info can be transferred
to external navigation equipment. e
polling (request reply) function checks
whether a specific ship is within the
communications range.
e M504A can store up to 100 MMSI
numbers and as many as 40 incoming
messages. Coupled with an Icom MA-
500TR Class B AIS transponder, calls
can be made to an AIS target using the
transponder without entering the tar-
get’s MMSI number.
One-button control is available for
transmitter power, toggling between
weather and voice channels, and making
a quick channel 16/9 selection. Volume,
squelch, and channel selection are knob
controlled. Scan modes include dual-
watch, tri-watch, normal, and priority.
A low-battery icon blinks when input
power drops below 10 volts. e M504A’s
large screen shows customizable chan-
nel comments, time and position, fre-
quency group, transmitter power, scan
tag, and transmit/receive icons. e unit
can accept a voice scrambler and comes
with a three-year warranty.
Bottom line: A good performer and
moderately priced, the IC-M504A oers
a number of useful and some unique
features. It gets a solid
Recommended.
icom ic-m604a
Icom’s most so-
phisticated ma-
rine VHF radio,
the IC-M604A,
features an alphanumeric keypad, large
display, and a $512 price tag, making it
the second most expensive test radio.
The only test unit with a keypad, the
M604A had the largest footprint.
It can connect to two optional remote
mics and can operate as part of an in-
tercom system. When interfaced with a
compatible GPS, the M604A will display
time and position data, boat course,
and boat speed. Like the M504A, it will
transmit and receive position data, and
can store up to 100 MMSI numbers and
40 messages. Users also can call an AIS
target without entering its MMSI num-
ber when the VHF is coupled with the
MA-500TR AIS transponder.
The IC-M604A has the same scan
modes, one-button and knob controls,
low-battery warning, and displayed in-
formation as the IC-M504A.
As for performance, transmit power
stability was rated Good, while fre-
quency stability and receiver sensitivity
were Excellent. Audio quality was also
top notch, with an output of 97 decibels,
tying it with the Garmin VHF 200 as
the loudest unit.
Bottom line: is radio has very good
overall performance and numerous
user-friendly features. It gets PS’s Best
Choice for a xed VHF with a keypad.
raymarine 218
e Raymarine 218 oers a host of use-
ful features, including a moderately
sized display and a mount-anywhere
microphone option. It can also connect
to an optional remote mic to be operated
321
Icom IC-M604A
The test group ran the gamut as far as front panel controls—from dedicated buttons and soft keys to traditional rotary knobs.
The displays on the Garmin 200 (#1), Icom 504A (#2), and Raymarine 218 (#3) all were rated Good.
electronics

july 2012 13practical sailor
as part of an intercom
system. The stan-
dard microphone
has buttons to con-
trol channel selec-
tion, scan, transmitter
power, local/distant receive
sensitivity, and quick 16 or 9 selection.
The Ray 218 provides one-button
control for toggling between weather
and voice channels, making a quick
channel 16 or 9 selection, and select-
ing menus. Volume, squelch, and chan-
nel selection are controlled via rotary
knob. Ray 218 functions that are menu
selected include local/distant receiver
setting, channel group, transmitter
power, scan mode, backlighting and
contrast, key beep, and speed unit se-
lection.
e 218’s phonebook will store up
to 50 MMSI numbers, and the radio
scans channels using dual-watch, tri-
watch, all channels, saved channels,
and priority modes. It will also store
three favorite channels. When it’s in-
terfaced with a GPS, the 218 displays
time, boat position, course, and speed.
It also has a powerful, manual or
automatic 30-watt hailer/foghorn. In
manual mode, it sounds a 400-Hz
tone as long as the push-to-talk but-
ton is pressed. Sound patterns are menu
selectable, and output volume is con-
trolled by so keys.
Performance-wise, the Ray 218
ranked highly. Testers found the 218’s
power output over the tested tempera-
ture and voltage ranges to be Excellent.
Frequency stability and audio quality
also were rated Excellent, while receiver
sensitivity was Good. It comes with a
three-year limited warranty.
Bottom line: e Ray 218 oers out-
standing performance and a long list of
user-friendly features. It gets the Best
Choice pick for a keypad-less xed VHF.
standard horizon gX2150
e GX2150 Matrix AIS+ has a built-in
dual-channel AIS receiver that allows
the VHF to display AIS target informa-
tion, including MMSI, call sign, ship
name, bearing, distance, speed over
ground, and course over ground, your
vessel’s position in relation to them, and
a closest point of ap-
proach alarm. It can
also output this
AIS data to a
compatible
GPS chart-
plotter. Like
the Icom M424, t h e S t a n d a rd
Horizon MATRIX AIS + GX2150 can
direct dial AIS targets, but unlike the
Icom, no standalone AIS unit is needed.
Users simply select the AIS target via
the so key menu to make the call. e
Matrix’s AIS functions use the radio’s
VHF antenna to receive data, so no
special or additional antenna is needed.
In addition to its 30-watt PA/loud
hailer with pre-programmed fog
signs, the durable, die-
cast Matrix features
user-changeable
channel names,
optional voice
scrambler, clear
voice noise can-
celing speaker mi-
crophone, 4.5-watt
audio output, NOAA weather alerts,
programmable scan, priority scan and
dual watch.
e GX2150 is also capable of sav-
ing up to 100 waypoints, which can be
navigated to via the radio’s unique nav
compass display that shows vessel SOG,
COG, and the bearing and distance
to the waypoint when connected to a
GPS source. e GX2150 also supports
a RAM3 remote access mic, allowing
remote control of all VHF, DSC, and
hailer functions (as well as an intercom
between the radio and second station
microphone).
Testers found the GX2150 to be a
solid performer. Power output over the
entire temperature and voltage ranges
was Good. Frequency stability was the
best of the group, while receiver sensi-
tivity and audio quality were rated Very
Good and Good, respectively.
Rated to IPX7, the GX2150 comes
with a three-year warranty.
Bottom line: If you’re looking for
AIS functionality combined with solid
VHF performance at an affordable
price, the GX2150 is the one for you.
It is our Budget Buy.
conclusion
When it comes to full-featured xed-
mount VHF radios—most of which
offer excellent performance—the fea-
tures, price, and warranty carry more
weight in our ratings. In our last test of
high-end radios, DSC operation made
us lean toward units with alphanumeric
keypads, which makes using the DSC
features much easier (entering contact
MMSI numbers and call data is faster
and easier with a keypad).
e advent of options like coupling
with the Icom MA-500TR Class B AIS
transponder (allowing for direct calling
of AIS targets without entering the tar-
get’s MMSI number in the VHF) allevi-
ates this concern to a degree. Keypads
are undoubtedly useful, but they
appear to be going the way of
the dodo, if our test group
is any indication.
(The Icom IC-
M604A was
the only test
VHF with a
keypad).
With good performance and a num-
ber of sought-aer features (not the least
of which is AIS), the Standard Horizon
GX2150 edged out the Icom IC-M504A,
Garmin 200, and IC-M424 to take our
Budget Buy recommendation.
For our top pick—based on perfor-
mance and features—it was a toss-up be-
tween the Raymarine 218 and the Icom
IC-M604A, so we divided the eld into
keypad haves and have-nots for nal rat-
ings. Buyerswho want the convenienceof
a keypad should go with the IC-M604A;
those who don’t can save roughly $83 by
going with the Ray 218.
Raymarine 218
Standard Horizon
Matrix AIS GX2150
GARMIN, 913/397-8200,
www.garmin.com
ICOM AMERICA, 800/426-7983,
www.icomamerica.com
STANDARD HORIZON,
800/767-2450,
www.standardhorizon.com
RAYMARINE, 603/881 5200,
www.raymarine.com
contacts
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