what are you running for electronics?

700 to 800 is a lot of $ for me only for a ff. With the gps talking to the vhf I don't see the connection other than emergency of course. Is it possable to transmit local to your bud this way over the vhf if it's a diffrent brand of gps recieving the info? I'm more than confused about this option.

Bluedog.
Your right, the gps sending an output to your VHF is strictly for emergency purposes. Only if your VHF is DSC equipped and your gps has a nmea output. With this connection made, you flip open the red emergency door on the VHF and press. This sends your Lat/Long. coordinates to the Coast Guard ( and other commercially equipped ships). This will not be fully implemented with the CG until '06. You have to register your VHF with the Coast Guard ( this takes about 5 minutes over the internet) It gives them the basic info about you and your boat if you ever use the DSC button.
I don't think you told us where you boat? Is it inland, great lakes, offshore? It makes a difference. If you strictly and inland lake fisherman on a tight budget, you might consider a handheld VHF. It won't perform near as well as a fixed mount but It will serve as a good backup when you decide to go with the fixed mount. No DSC with the handheld. Besides if your inland, DSC would be near useless to you.
I still think, handheld cheap Garmin GPS, VHF as you choose, and a Garmin 160/240 blue (as mentioned, they are discontinuing the unit) The ONLY difference between the 160 and 240 is pixel count. Same exact software and functions.
Hope this clears some things up some.

Mike

one more quick note. DSC is not exactly for strict emergencies. If you buddies have dsc capable radio's they can call up our radio and get a fix on your lat/long position.

Mike

[chumbucket]

Seakindly, yup on the thermal imaging. Many commercials have been using color CRT's for years. I know one guy that can tell you what type of fish are being shown on the finder just by the color of the return signal. He was right every time.
And, yup on the DSC capability on calling your bud's with it. You just need to know their DSC assigned number to send to them.

[chumbucket]

There is some info on the USCG website regarding the DSC calling. As was explained to me by a friend;

All that's involved in setting up a "group", is for every member of the group to input the GROUP MMSI number into their radio. It is entered on a screen specifically for group numbers. You don't do anthing to your personal MMSI number to do this. I think, actually, that group members could use any number to set up a group, as long as its first digit is a zero. They just all have to use the same group number for the group DSC funtion of our radios to work. The USCG explanation said that to pick a GROUP MMSI number, all you do is take any personal MMSI number in the group and put a zero in front of it and drop its last digit. So, 336234567, would become a group number of 033623456, and all members would enter 033623456 into their respective radio's group MMSI number set-up.

As I understand it, any radio that is turned on and within range, that has that GROUP MMSI number set up, will respond whenever any radio in the group that also has that group number set up, sends a msg using the group DSC function (DSC is Digital Selective Calling). When a group DSC msg is sent, two things happen: 1. All radios with the group MMSI number will first automatically switch to the channel the sender has selected for his group DSC call, and 2. all members (a "member" is defined as anyone with that specific GROUP MMSI number set up on the radio), can then communicate with each other just as if they were making a conference call on telephones.

So, suppose five friends who are using the same Group MMSI number are out one day and one of them gets into fish. If he wants to (A BIGGGG ASSUMPTION!!!), he could make a GROUP DSC call and all the other four would automatically switch to that channel and receive his message. The other four could call back and they would all be on the same channel for a certain amount of time. After some delay, if there is no further calling on that channel, all their radios would automatically jump back to the channels they were on when the group DSC call was first made (although I am a little unsure about this part).

I also THINK the call automatically sends lat-long info to all group members, as long as the sender has a GPS NMEA connection and the GPS is turned on.

The DSC funtion of radios is set up to send at least four types of DSC calls: individual, group, all ships and maritel telephone, in addition to the distress calls. Without getting into all of the options, if you selected "individual" for a DSC call, then only that individual's radio would switch to your selected channel. For a group call, all members of the group would automatically jump to that channel. In both cases, the receiving radios would display the caller's lat-long and some other stuff.

Radios have built-in timing protocals for handling DSC messages. Certain things happen, for example, when you make a DSC call and no one in the group is up and operating. Certain time delays go into effect and certain msgs show up on the sender's radio telling him there's no one around, basically, and the radio jumps back to the previous channel.

BTW, you can get an MMSI number through BoatUS. They send your number to the USCG in the event of a distress signal is sent.

That's interesting. I've never heard it explained that way for group calling.
I don't know about you guys, but every spring I need to sit and "play" with my VHF because I forget how the thing works. Keeping the book in the boat is crucial for me. How many would use that function I wonder?

Thanks for that explanation. But than again, I've got no friends that I boat with that aren't on MY boat!

Mike

The garmin 162 looks like all I need for now with a high 300$ price tag. Heres the question It says I can down load software to it I assume if i'm going off Ri coast I can download a chart that will have info just lage a navchart and just superimpose my local on top of it correct? Other ? is I have a starboard t-top does this mean I'll need an external antena? I know my handheld garmin Etrex can't pick up in my car or house.

Cmon CB, are you just yankin my chain or what ???

"THERMAL IMAGING" and "DIFFERENT TYPES OF FISH HAVE DIFFERENT BODY TEMPERATURES".

Almost all fish are strictly cold-blooded animals - that means their body temperatures are the same as the water they are in. Some tunas are an exception - they have the ability to raise their body temps slightly above the surrounding waters.

Now if you want to tell me that fish finder does a very good job at discriminating between the different body shapes that different species of fish have, and even that this differing sonar (sound not temperature) reflection can be displayed as a different color -- yeah, that I could believe.

But a fishfinder that uses thermal imaging to identify different species of fish by body temperature ???

No way, CB. I was born at night, but not last night. ;)

[chumbucket]

Ain't trying to slip one by ya. Actually, it's a combination of temperature and body density that comprise the different color images displayed on the screen.
But hey, don't take my word for it. Ask a comm. guy. :-X

ok CB, my friend, since you say you are being serious.

Now you are talkin about body density. That is at least believable because different species of fish could have enuff difference in body density to display differently in much the same way as different bottom densities such as sand vs. mud display differently.

But "differences in body temperature" ???

No way.

1) Fishfinders use sonar. They send and receive sound waves at specific frequencies. They don't measure temperatures at depth.

2) Fish are cold-blooded animals. Their body temperature is the same as the water they are swimmin in, regardless of species. Let's say the water is 50 degrees and a bass and a blue are swimmin under your transducer. Both fish are at 50 degrees.

3) Let's say that the fishfinder did measure temperatures at depth with "thermal imaging", and not with sonar. Then those fish would be invisible because they are at the same temperatures as the surrounding water. (When a fishfinder is displaying a thermocline or temperature break, it is able to show water at different temperatures because water at different temperatures has different densities. So does water of different salinities.)

I hope this helps.