VHF Marine Radio Question

[SWP]

Hello Everyone. Looking for opinions on Marine VHF Radios. We hail ships 24/7 in order to get arrival times and other info. ETAs' are very important to us so we want to reach out and get them ASAP. Currently, we are using the ICOM IC-604 units.

I'm looking for input on whether or not this is our best choice radio. Is there a better radio for haling? Any suggestions on the best antennas? Our antennas are mounted approx. 60+ ft above water.

Any input would be appreciated.

Thanks In Advance

 

[Wire Weasel]

A typical high quality base antenna is a 1/2 wave design which for the marine band is around 12 feet long. If your vertical stick antenna looks like that then you're in the ball park.

The typical marine base or 12 volt "mobile" radio on a power supply does 25 or 50 watts as max. If that is what you have you consider adding an amplifier, and pursuant to any applicable rules (I don't know them.)

VHF amplifiers are silly common and something like a 250 watt'er would provide a substantial boost. Your local commercial radio shop..... like a Motorola dealer, could easily hook you guys up.

Such an amp will typically be a 12 volt device and require a power supply of sufficient amperage to run it smoothly. IF you are currently using a "mobile" 12 volt radio on a power supply now, it is unlikely that you have a really huge power supply that will handle the radio and amplifier together. The power supply you have is probably only big enough for the radio itself.

Hope any of this helps

Good luck

 

[IMD262]

If I'm not mistaken you are limited to 25 watts on the VHF Marine Band.

 

[SWP]

Thanks for the replies!

The antennas we have are about 12' long and according to our license, we are limited to 50 watts. However, the license that has 50 watts on it is very old. They're looking for a copy of our most recent license as we think the one we had on site is missing. One of the supervisors thinks we were allowed an increase in output.I think we evacuated the newer license with us for a hurricane and misplaced it.

Any recommendations for a particular brand radio? As mentioned we're using the IC-M604. At one time we used a Sailor radio and I thought it seemed to outperform the ICOM units. Then, it got struck by lightning.

 

[Beetle]

The current version of Part 80 of the FCC rules shows 25 watts maximum for the Marine VHF service. Some Marine services, especially those using HF rather than VHF, can use quite a bit more, depending on exactly what the license states.

 

[Shockwave]

Many years ago I did a VHF base installation for a local commercial fishing company. We provided them with a legal 100 watt ERP by using four folded dipole antennas fed in phase through a coaxial harness. This gave a 6 db increase in both transmit and receive. One thing you have to watch out for with many 12 foot fiberglass antennas is that they often are nothing more then an empty tube at the base with the antenna only using the top few feet. The better ones are collinear and use the entire length offering gain. You would have to know the exact model to confirm this.

 

[Nursecosmo]

A typical high quality base antenna is a 1/2 wave design which for the marine band is around 12 feet long. If your vertical stick antenna looks like that then you're in the ball park.

Since when does Marine VHF operate on 7 meters? A 160Mhz half wave antenna should be around 3 feet long.

Perhaps you are refering to a colinear high gain array. Marine VHF radio - Wikipedia, the free encyclopedia

 

[Captain Kilowatt]

Since when does Marine VHF operate on 7 meters? A 160Mhz half wave antenna should be around 3 feet long.

Perhaps you are refering to a colinear high gain array. Marine VHF radio - Wikipedia, the free encyclopedia

He IS talking about a colinear antenna. See nursecosmo's post right above your's? See the mention of 12 foot antennas and the part about the colinear types? Commercial VHF antennas are quite frequently collinear types. Some 2m antennas are 22 feet long.

 

[SR385]

I'd say those Icom units are fine. With FM, which is what Marine VHF is, there's not a ton of difference beyond the build quality. You won't get much signal difference between two 25W radios for example. Maybe audio quality, but the way FM works, that 25W will capture the receiver at the same distance as the next 25W radio.

Icom makes solid stuff, no reason to think you'll have trouble with those.

My biggest tip is to mount the head somewhere close so the mic cable isn't being strained all the time.

 

[Moleculo]

My biggest tip is to mount the head somewhere close so the mic cable isn't being strained all the time.

You do realize that on a boat, "the head" has an entirely different meaning, right?

 

[Nursecosmo]

He IS talking about a colinear antenna. See nursecosmo's post right above your's? See the mention of 12 foot antennas and the part about the colinear types? Commercial VHF antennas are quite frequently collinear types. Some 2m antennas are 22 feet long.

Indeed they are, but a half wave Marine VHF antenna is not 12' long. I'm just picking knits. It's a bad habit I have. I know that Wire Weasel knows the difference.

 

[Happy_Hamer]

I take it your not happy with the current setup?

Maybe something is wrong in the, ANTENNA, COAX, RADIO, POWER SUPPLY, GROUND?

The specs on that ICOM shows that radio puts out 1 watt and 25 watts, maybe someone has it on 1 watt?

From the information I found on that radio, it is everything plus more than what you need. If you decide to buy a different unit, i will buy that ICOM!!!!!

If you stick with your current set up you can consider an amplifier, licensing for extra power is something your company can handle.

Before throwing an amplifier on be sure you know the specifications of your current antenna and make sure it can handle the power.

vhf amplifiers 156-161 MHz

Look at that page, depending on the budget I would look at the CMSR 200 or the CMS 210 TR. The CMSR 200 requires an external 13.6 vdc, 23 amp power source. The CMS 210 TR has a built in power source and requires 220 VAC

These amps have a built in pre-amp to help your receive and you would increase your output power from 25 watts to 200 watts. That may not seem much but in VHF it is huge!

Call Richard Junior at 8541 Electronics and tell him this forum referred you, he can probably help you with your commercial needs.