july 2012
9
practical 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 Identification 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
benefit, 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-
tification. 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 identified 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 five
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. The 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. The FCC
mandates an accuracy of 10 parts per
million (about 1550 Hz off 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
e l e c t r o n i c s
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
