OK
How high is the feedpoint ('input') of the antenna?
If you can give us the model number and make of the antenna, that would help considerably.
What about the answers to my other questions?
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Need help to amplify my VHF marine radio for fishing offshore/ increase range
- Thread starter xrayengineer@cfl.rr.com
- Start date
OK
How high is the feedpoint ('input') of the antenna?
If you can give us the model number and make of the antenna, that would help considerably.
What about the answers to my other questions?
Wooden hull or metal? Metal hull would be ideal as long as there's good bare metal contact with the water, and not just via the motor/propeller. Wooden hull is more of a problem. You still need the metal-to-water contact. Navy mine-countermeasures ships (and others) use two sheets of copper, one on either side of the keel, bonded together and to the electronics/radio equipment. This is more of a help on HF, but VHF will benefit from it as well.
40 miles is a stretch for VHF in my opinion. Not impossible but not guaranteed either.
All you can do is set up your system as best as you can and learn your limits and avoid going outside it.
All you can do is set up your system as best as you can and learn your limits and avoid going outside it.
I get about 35 miles, simplex 45w on 2m, with a Diamond F23 mounted with the base at ~31 ft, fed with 80 feet of crappy no-name RG8U, over hills, trees, and other terrain.
If he can get a vertical in the air, as said, height is might.
I'm going to go against the grain of the other recommendations and disagree with them a bit. First a qualifying statement: They are all correct in a normal communications, especially on land, situation.
Here's why I disagree and actually think that the amplifier is a good idea for an emergency (although illegal): The U.S. Coast Guard runs a lot more than 25 watts, and they're the only stations that count when you need to be rescued. I have been 40 miles offshore in a 25 foot sport fishing boat when you can't make out other stations that are at port, but you CAN clearly hear the Coast Guard. Not only does the Coast Guard user higher power levels, they also must be using some type of antenna system with huge gain. Here is a link to an interesting thread from some folks that monitor the CG near me: Southern California Coast Guard Transmitter Locations - The RadioReference.com Forums
My point is that the "who will be able to hear you" argument against the amplifier is moot. The Coast Guard will likely be able to hear you if you're that far out, even if noone else will. And they are the only ones that matter.
On a sport fishing vessel, there is only so much you can do to get the antenna high without it turning into a big structural hassle. Yagi's and rotors are completely impractical, not to mention that most rotators would not last in the saltwater air. I would challenge that anyone who recommends something like that has not spent much time on the ocean in a small boat and has not witnessed how much everything gets beat up and fails. Just the constant pounding of the boat against the sea surface while doing 25 knots will kill the yagi system the first time out, if the salt water didn't get it first. It's difficult enough to keep bait tank pumps, fish finder transducers, and all the necessary electrical stuff in working condition. A yagi system will never make it. The ocean is not kind to its visitors.
For antennas, the best thing you can do is to mount the highest gain marine antenna in whatever spot is provided for your antenna and call it good. Unfortunately, most of the marine antenna manufacturers are probably a little "generous" on their gain figures to really be able to know what you're getting. You don't have to worry about installing ground planes because ALL marine antennas are either 1/2 wave (the cheap ones you don't want) or some type of phased array over a 1/2 wave (most are these and are much taller). You want the latter as it will have higher gain. You should also inspect your coax, connectors, and antenna annually to replace anything that has become corroded by the salt air. Also make sure that the antenna can handle whatever power you're planning on putting into it. I also wouldn't mess with larger diameter coax on a 27 foot boat because your cable run is probably about 15 feet maximum (if that). There isn't enough line loss in 15 feet at VHF to worry about. Just use good quality RG-8x or similar.
BTW, I have communicated with the Coast Guard in a fiberglass fishing boat with a regular VHF Marine radio at about 40 miles out. Yesterday I was out on the water on the back side of Catalina Island, which is about 30 miles out. If I was much farther out than that, I would probably want a bit more power, too. The ocean is a big place and it is not your friend. Until you've been out far enough to where you can't see any land in a small boat, you don't truly understand the feeling of helplessness on the ocean.
Here's why I disagree and actually think that the amplifier is a good idea for an emergency (although illegal): The U.S. Coast Guard runs a lot more than 25 watts, and they're the only stations that count when you need to be rescued. I have been 40 miles offshore in a 25 foot sport fishing boat when you can't make out other stations that are at port, but you CAN clearly hear the Coast Guard. Not only does the Coast Guard user higher power levels, they also must be using some type of antenna system with huge gain. Here is a link to an interesting thread from some folks that monitor the CG near me: Southern California Coast Guard Transmitter Locations - The RadioReference.com Forums
My point is that the "who will be able to hear you" argument against the amplifier is moot. The Coast Guard will likely be able to hear you if you're that far out, even if noone else will. And they are the only ones that matter.
On a sport fishing vessel, there is only so much you can do to get the antenna high without it turning into a big structural hassle. Yagi's and rotors are completely impractical, not to mention that most rotators would not last in the saltwater air. I would challenge that anyone who recommends something like that has not spent much time on the ocean in a small boat and has not witnessed how much everything gets beat up and fails. Just the constant pounding of the boat against the sea surface while doing 25 knots will kill the yagi system the first time out, if the salt water didn't get it first. It's difficult enough to keep bait tank pumps, fish finder transducers, and all the necessary electrical stuff in working condition. A yagi system will never make it. The ocean is not kind to its visitors.
For antennas, the best thing you can do is to mount the highest gain marine antenna in whatever spot is provided for your antenna and call it good. Unfortunately, most of the marine antenna manufacturers are probably a little "generous" on their gain figures to really be able to know what you're getting. You don't have to worry about installing ground planes because ALL marine antennas are either 1/2 wave (the cheap ones you don't want) or some type of phased array over a 1/2 wave (most are these and are much taller). You want the latter as it will have higher gain. You should also inspect your coax, connectors, and antenna annually to replace anything that has become corroded by the salt air. Also make sure that the antenna can handle whatever power you're planning on putting into it. I also wouldn't mess with larger diameter coax on a 27 foot boat because your cable run is probably about 15 feet maximum (if that). There isn't enough line loss in 15 feet at VHF to worry about. Just use good quality RG-8x or similar.
I'm guessing that an open console fishing boat is probably fiberglass, since that's what most of them are. There are very few made that are aluminum of that size, and probably exactly zero that are still made out of wood.
BTW, I have communicated with the Coast Guard in a fiberglass fishing boat with a regular VHF Marine radio at about 40 miles out. Yesterday I was out on the water on the back side of Catalina Island, which is about 30 miles out. If I was much farther out than that, I would probably want a bit more power, too. The ocean is a big place and it is not your friend. Until you've been out far enough to where you can't see any land in a small boat, you don't truly understand the feeling of helplessness on the ocean.
Hey Mole,
Remember that ALL CG antennas are as high as they can be. Fixed station is on a tall tower, and the small boats are up high. To the OP, shakespear, among others, sell extension mast sections that screw on the antenna mounts, and accept the antenna section. Or, the makers sell TALL antennas designed for larger boats and offshore work. They are 16+ feet and up. I would check whether you have a cheapie, upgrade the antenna to a good one, get an extension mast and use some good cable. Don't cheap out. (And don't be shocked at the price of a quality antenna.) Also, check the pl-259. I have seen some horrendous installations in my time, some that wouldn't make it across the creek, more less across the pond.
Is this your boat? Do you have a tower? Flying bridge?
And, as you learned, they send out a search party when you deploy that EPIRB.
Is the EPIRB registered? You can add contact info when you register one, and it wont show up as a ghost.
Remember that ALL CG antennas are as high as they can be. Fixed station is on a tall tower, and the small boats are up high. To the OP, shakespear, among others, sell extension mast sections that screw on the antenna mounts, and accept the antenna section. Or, the makers sell TALL antennas designed for larger boats and offshore work. They are 16+ feet and up. I would check whether you have a cheapie, upgrade the antenna to a good one, get an extension mast and use some good cable. Don't cheap out. (And don't be shocked at the price of a quality antenna.) Also, check the pl-259. I have seen some horrendous installations in my time, some that wouldn't make it across the creek, more less across the pond.
Is this your boat? Do you have a tower? Flying bridge?
And, as you learned, they send out a search party when you deploy that EPIRB.
Is the EPIRB registered? You can add contact info when you register one, and it wont show up as a ghost.
I dont think an amplifier would be the best route,it would help increase your range with other boaters but without a pre amp you would would not hear them. Get the best antenna you can and mount it as high as you can. As stated in other posts the coast guard is probably using antennas mounted at a high elevation. When you cant get help via radio and are dead in the water without steerage the EPIRB is the best option.
A web site called "the hull truth" can help you with you boating questions. There was just a long post on there about when to and not to set off the EPIRB.
A web site called "the hull truth" can help you with you boating questions. There was just a long post on there about when to and not to set off the EPIRB.
Remember, most VHF amps include a pre-amp. I don't think an amp is the best/only route, but I do think it is an additional tool that could be helpful, even if you can't hear the other stations. Your EPIRB doesn't RX anything - it's just a beacon. So it's not useful because it can't hear? Even if your VHF can't hear another station because it's able to talk farther distances than other stations, that doesn't prevent THEM from hearing you calling distress with your GPS coordinates. Also don't forget that the VHF also can send the DSC/MMSID info when activated, which is a data mode that includes the GPS coordinates. That can also be used without any reception on your part to help the Coast Guard locate you, just like a beacon. If you're going to go places on the ocean that can put your life in jeopardy, having every tool available isn't really that bad of an idea.
Personally, I think you need a better, bigger boat. I don't go offshore in a single engine boat, unless it is a trawler with a get home engine. My life is just too valuable. Remember, offshore, one word is key to survival...REDUNDANCY!
Throw on a transom mounted kicker, with a separate fuel system,at the very least.
For comms, get your ticket and install a ssb unit.
Throw on a transom mounted kicker, with a separate fuel system,at the very least.
For comms, get your ticket and install a ssb unit.
I think the Amp he linked to has a pre amp built in.
I think it will take a combination of up grades in Antenna AND power....and then it is still not a "for sure" thing.
If you are really concerned the Sat Phone is about as "sure" as you can get.
73
Jeff
I think it will take a combination of up grades in Antenna AND power....and then it is still not a "for sure" thing.
If you are really concerned the Sat Phone is about as "sure" as you can get.
73
Jeff
Thanks for the info, I am going to try to answer the questions that have been asked in the previous posts. I am sure I will forget a few, but lets see...
This is a center console, fiberglass boat. It has an aluminum T-Top.
The Antenna is a Shakespeare Galaxy 5225-XT. Here is a link:
Shakespeare Marine Antennas Specifications: Galaxy 5225-XT VHF Marine Band
The cable is RG-8/X, it is only as long as it needs to be, perhaps 6 feet. However, I also have it going through a Shakespeare Style 4357-S splitter that allows the antenna to be used for the AM/FM radio as well. Here is the link for that:
Shakespeare Marine Antennas Specifications: Shakespeare 4357-S AM-FM
The connections are crimped on PL259 that I covered with silicone dielectric grease before plugging them in. I mean I put the grease all over the female jack on the radio and then connected the 259 from the cable. There is no corrosion.
I have have tested this setup on land (i know, i know) with the boat in my yard and me in my car with my vhf handheld. I can receive the signal from from at least 3 miles away as the crow flies. This is with pine trees and houses in between.
Hopefully this info is helpful. Like I said, my goal is to get the most range and reliable communication.
Thanks Again!
This is a center console, fiberglass boat. It has an aluminum T-Top.
The Antenna is a Shakespeare Galaxy 5225-XT. Here is a link:
Shakespeare Marine Antennas Specifications: Galaxy 5225-XT VHF Marine Band
The cable is RG-8/X, it is only as long as it needs to be, perhaps 6 feet. However, I also have it going through a Shakespeare Style 4357-S splitter that allows the antenna to be used for the AM/FM radio as well. Here is the link for that:
Shakespeare Marine Antennas Specifications: Shakespeare 4357-S AM-FM
The connections are crimped on PL259 that I covered with silicone dielectric grease before plugging them in. I mean I put the grease all over the female jack on the radio and then connected the 259 from the cable. There is no corrosion.
I have have tested this setup on land (i know, i know) with the boat in my yard and me in my car with my vhf handheld. I can receive the signal from from at least 3 miles away as the crow flies. This is with pine trees and houses in between.
Hopefully this info is helpful. Like I said, my goal is to get the most range and reliable communication.
Thanks Again!
Another thought, folks here have mentioned the higher quality cable like the LM240, but all these antennas have the cables already connected at the antenna end. Are there better antennas for boats that have just a female PL-259 connection on it instead? Otherwise how would you retrofit?
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