#Handheld #VHF #Radios IC-M94D
Frequently Asked Questions
I am getting feedback on my Marine VHF radio from my hailer horn?
This is caused by your microphone picking up the output of your hailer horn (feedback). This can be mitigated by one or all of the following:
1. Install the hailer horn further away from the radio.
2. Be sure the hailer horn faces away from the microphone.
3. Use only as much hailer audio power as you need.
4. Verify the polarity of the hailer wiring to the radio. Reverse polarity will cause feedback.
What types of information do AIS transponders transmit?
AIS transponders typically transmit the following information, depending on class.
• Vessel name, MMSI number and call sign
• Type of vessel (such as passenger, cargo, fishing)
• Vessel’s position (current latitude and longitude)
• Course over ground (COG)
• Speed over ground (SOG)
• Heading from your vessel
• Closest point of approach (CPA) (distance)
• Time to closest point of approach (TCPA)
• Vessel’s dimensions (length, beam, and draught)
I want to connect an external antenna to marine handheld VHF radio. How do I do this?
Even though for range, there is no substitute for a fixed marine set, we do realise that there are smaller boat owners that want a smaller solution for their communication requirements.
Icom have an AD-98FSC antenna connector adapter that will convert to a BNC socket. This adaptor will fit the IC-M25 / IC-M35 / IC-M37 / IC-M85E / IC-M93D. You would then need a BNC male plug on the end of your antenna cable to go into this adapter. You could use a second adapter to achieve this (SO-239 to BNC female).
For the IC-M73 you can use the adapter SMA.007 which requires no second adapter as it will accept a PL259 plug without the need of a BNC plug.
However, if you do use this approach you will:
• Get a small loss going through the adapters and connectors.
• Get loss over the cable run: the longer the run the greater the loss.
Our advice would be where possible to choose a fixed marine VHF radio.
What GPS format does Icom use to display GPS coordinates on its marine radios?
It is shown in the Degrees/Decimal Minutes format: e.g. 47.42.2147N 123.8.7456W.
When should I operate my Marine VHF radio on low power?
In general it depends on how far away the radio is that you are trying to communicate with. There are some channels that automatically require the high or low power setting. Keep in mind is that the lower wattage, the less power used, thus the longer the batteries will last.
What can I do to prolong the life of my marine VHF radio?
To prolong the life of your marine handheld or fixed VHF, thoroughly clean your radio after every use. It is important because the radio's keys, switches and controllers may become inoperable due to salt crystallisation.
The most effective way of doing this is:
• First wash it in a bowl of warm water
• Then, with an old toothbrush, clean any exposed metal surfaces including the volume control knob and battery terminals
• Then dry the unit thoroughly - if you're not sure LEAVE IT TO DRY.
• PAY CLOSE ATTENTION TO THE BATTERY TERMINALS - make sure they're cleaned and DRIED after every use.
DO NOT wash the transceiver in water if there is any reason to suspect the waterproofing may not be effective. For example, in cases where the transceiver/battery pack is cracked or broken, has been dropped, or when the battery pack is detached from the transceiver.
What are marine VHF channels used for?
Some of the marine channels have designated functions. The important numbers are as follows:
Ch 16 is the Distress, Safety and Calling channel. This is used for calling another vessel before moving to a different channel, or for safety and distress transmissions. Before using Ch16 listen for a few moments to check you are not interrupting an important transmission such as a Mayday.
Ch6, Ch8, Ch72 and Ch77 are designated intership channels. Once initial contact has been made all further transmissions should be made on one of these channels.
Ch67 is the small ships safety channel. The Coastguard uses this as their working channel.
Ch70 is the DSC channel. Only for the transmission of digital calls, Ch70 should never be used for voice transmissions.
Ch80 is the normal channel for UK marinas.
The other numbered channels are allocated for public correspondence, port operations and bridge-to-bridge working.
My mounted VHF radio, or SSB radio, seems to have a problem. The display lights dim when I transmit
This behaviour is caused by an insufficient power supply, or a bad electrical connection somewhere between the battery (or a power supply) and the transceiver. Check your electrical connections and battery. Pay special attention to the in-line fuse holders and power cord terminals on the battery side.
Can I use my Icom mounted VHF radio, or an SSB radio, on a vessel with a 24V electrical system?
Only if you purchase a separate power converter that will convert 24V DC into 12 Volt DC. All Icom mounted VHF and SSB marine radios are designed to operate with 12V power systems. Connecting them to 24V will result in immediate failure of the radio due to over voltage. It might even damage the radio beyond repair.
Are your waterproof marine radios really waterproof?
They are conditionally waterproof. For example, the IC-M31 can withstand being submerged in one metre of water (about 3ft) for 30 minutes with no water intrusion. If the radio ever goes overboard, you should retrieve it as soon as possible. Remember that even submarines will get crushed if they submerge beyond certain depth. We make quality radios, but we cannot change the laws of physics!
If your Icom radio does get submerged then a good practice is to rinse the radio with tap water and dry thoroughly to prevent a salt build up as salt can cause serious corrosion. After repeated exposure to spray all battery contacts should be inspected, cleaned and lightly greased. Knobs should also be removed and control shafts cleaned and re-greased likewise. After any exposure to moisture the radio should be thoroughly dried.