Icom M412 Review
The new release Icom M412 marine VHF radio fits right smack in the middle of the Icom marine VHF fixed mount radio lineup. This boat radio is features all the basics plus built-in Class D DSC capabilities all in a compact package.
The M412 ships with the radio and attached microphone, a plastic tilt bracket suitable for both overhead and dashboard mounting, a fused power cable, and an instruction manual.
To flush mount this radio you’d have to improvise your own mounting system or purchase the Icom MB-69 flush mounting kit.
Wire leads extending from the back panel of the radio let you connect to an external speaker and NMEA0183 devices.
The radio face measures 6.3-inches wide by 3.1-inches high. The radio housing extends back a tad under 5-inches from the front panel back, which is where the radio would contact the panel in a flush mount setup. A flush mount step approximately a quarter inch wide runs around the face back. No gasket is provided to seal a flush mount against water intrusion. Making your own gasket or sealing with waterproof chaulk should provide an adequate seal.
Controls and Operation
This radio, officially known as the Icom IC-M412, has two knobs located on the right side of the front panel, the top one turns the radio on/off and controls audio volume while the bottom knob sets the squelch level. Channel selection is made with up/down arrow keys located both on the radio front panel and the microphone. Dedicated pushbuttons offer single press control for quick selection of channel 16 or 9, some scan functions, weather channel selection, and menu. Another pair of button serve as menu Enter and Clear keys.
Channel group is selected by simultaneously pressing the up/down arrow keys on the radio front. Pressing other sets of keys at the same time or in a specific fashion will allow you to adjust the display backlight setting, clear all channels tagged for memory scan, activate the AquaQuake function, and customize channel comments. For most of us this will require the memory aid of looking up the key combinations in the manual to access these functions. Not ideal in my opinion. A DSC distress call button is located on the front panel under a red spring loaded cover. Lift and press to activate.
The M412 will interface with a variety of gear using a NMEA0183 interface. When connected to the Icom MA-500TR Class B AIS the M412 can call an AIS target without the need to manually enter the MMSI number.
Icom M412—Added Features
This radio does not have a significant added feature list beyond the basics. It will connect to and power an external speaker and does have an Icom exclusive called AquaQuake which uses a tone burst though the radio speaker to clear any accumulated water. Water in a speaker can muffle the output and reduce voice clarity.
The M412 has a built-in low voltage alarm that will display a battery icon onscreen if input voltage drops below 11 volts. Raising the voltage above this level reset the alarm to off. There is no audible warning associated with this alarm.
Typically Icom marine VHF radios have efficient transmitters and the M412 is no exception. When transmitting at full power the unit amp draw was a meager 3.8 and at low power only .9 amps. We gave the receiver sensitivity and channel separation both good rating based on the factory specifications listed. Audio output was a respectable 92 dBA with volume at maximum while listening to a weather broadcast. As one would expect, there was some voice distortion noted in the voice output at high volume levels. Overall the Icom M412 audio system proved to be more than adequate for a radio in this price range.
I am rating the M412 display screen good. This Icom VHF boat radio has a 2.6-inch monochrome segmented LCD display screen. Channel numbers display full height in the center section of the screen. The left side of the screen is filled with a list of oft used icons while the top right has a seven character display for channel comments and position information, any piece of data too long to display all at once with scroll across the screen.
The M412 is rated waterproof to IPX7 standards which means the radio could be submerged to a depth of one meter for 30 minutes without sustaining damage.
The Icom M412 has a number of channel scan modes available; it can scan all channels in numeric or priority order based on your preference. Dual Watch or Tri-Watch modes reduce that scanned channels to two or three respectively. Channels are tagged for scanning by the user with an onscreen icon indicated which channels have been tagged.
Digital Selective Calling
The Icom M412 is rated as a Class D radio. This means it has two receivers built-in, one for voice communications and the second to continuously monitor channel 70 for any incoming DSC calls. Before you can proceed with using any DSC functions you must enter your MMSI number. This is especially important today as penalties for improper marine VHF radio when making DSC calls have increased significantly. Once your MMSI number has been properly entered in the M412 and you have connected the radio to a GPS unit you will be able to make DSC distress calls that transmit your information and position data. The M412 will store up to 100 MMSI numbers with up to 10 characters names associated with each.
The Icom M412 is an entry level radio with all the basic features you would expect in a radio of this caliber as well as full Class D DSC capabilities now required of any new release marine VHF radio.