And if you are interested in ham texting options:   http://www.aprs.org/aprs-messaging.html sk (really!)

I'll probably go with my own APRS digipeater and APRS ht's not on an APRS frequency and mix voice and APRS messaging.

http://www.itofisher.com/mito/archives/ito.ppp.pdf   (if you're interested in how voice/text communications are changing, especially in the young (Japanese in this case)   

sk

I didn't know what category to put texting and in particular texting between ham radio HT's. I think this is an upcoming topic area which would possible include DSTAR and newer APRS protocols which have their own forums. Texting as per packet radio will often find a radio path to the destination when voice would not, over the same path. This phenomena is similar to texting over the cellphone network when a constant voice transmission is not possible a text message can find a path for the few seconds needed. What do you think ... a separate forum for VHF texting?  nL7sx 

Thank you John........I'm not sure.........but it is very interesting.

I was referring to my other message. http://www.eham.net/ehamforum/smf/index.php/topic,84956.0.html

so the answer is: 2 computers/displays, 2 APRS transceivers (computer compatible), 2 sets of imagery software, and the usage of these in a mobile environment. Without the computers/displays it will still work but is not so friendly as in my opinion just distance and direction limit efficiency.

VX-8DR will not work with UIview or APRS point says:
http://www.worldwidedx.com/handitalkies/129782-yaesu-vx-8gr-vs-kenwood-th-d72-2.html

That is helpful. A local ham on our net tonight explained the VX-8DR & GR (GPS/bluetooth) in some detail but linking the radios to software and computer displays, etc was not in his knowledge base. The APRS message line is probably of many more characters than the frequency field. Doing all this while mobile is problematic :-) 

I've used APRS many times over the years. It should work like this: Ham1 mobile is broadcasting position on APRS with a one or two line message stating the frequencies he is monitoring. Ham2 mobile notes on his computer he is within radio range of ham1, reads message, decides to give ham1 a call. Ham1 notes ham2's location on his computer turns up his receiver volume and answers the call.

The above sounds simple but I've never seen it done. I'd guess that the newest APRS VHF mobile may have an outboard vector line graphic display and the newest APRS VHF handheld might have a direction & distance indicator, but what is the best option for the above conditions? Your answer could include radio model, radio accessories required, computer display size. operating system, GPS required, software for imagery on computer, software to display APRS text information, etc.

Most hams know that eating a cheeseburger while slapping out 30 WPM code on a knee key and driving requires discipline. Please drive safe! 

Thanks...now I'm going guess at what is required for a mobile 2-way APRS station.

I want to do some close in tracking and wonder if a VX-8DR can pass aprs information to another VX-8DR?

Perhaps you meant MIL-STD 188-110A which might be on Multipsk at this time?

http://mt-milcom.blogspot.com/2009/07/multipsk-to-add-mil-std-188-110a.html

Interesting suggestion and lack of acceptance of speeds above 300 is a big handicap. Is thee a good reference for MIL-STD 110A?

W8JX:  I'm using color imagery: shifting between 10 meter and 1 meter where needed. Also considering moving to some 1/3 meter color imagery as it's now available from DeLorme. I suppose I could rig up a 27" screen in my pickup (the imagery and gps will display to it) but the advantage of being able to read the small GPS screen can be analogized to using a magnifying glass to read microfiche without the microfiche reader, if you've been around that long :-)       

When I ordered my first set of 'professional' glasses I asked the optometrist if they had a lens I could piggy back on these with 3X, set above the left lens for viewing my PN-30 DeLorme GPS. Nope! The screen is about the size of a cellphone and as I could never see it very well I added a netbook computer in parallel for out-back horse, marathon and motorcycle races helped by our local radio club, here on the desert west of Death Valley. The other day at Harbor Freight I saw an inexpensive magnifier (loupe) that mounts on eyeglasses and to my surprise it works wonderfully. It has several magnifications from 2 lenses that can be used above the glasses by looking up, used through the plain lens normally used for driving or in combination with the 1.25 of my reading glasses on the lower portion 1.25 for reading. Max magnification would be maybe 12x. Of course these magnifications can't be safely used while driving but neither can the netbook, but when one is driving over dirt roads at very low speeds looking over the glasses through the 3x of the loupe to see the GPS is possibile. Stopping and moving the two lenses over the glasses reveals a surprisingly good magnification of a small screen with every pixel clearly visible so it is now unnecessary to take the netbook. Another important item when your in the field with your 'bugout' bag or field pack .   

TNX to all, especially AA4HA. Only one transmitting station of many had the problem in the portable repeater instance. It was one of the furthest stations from the repeater. The second case is still under investigation, almost line-of-sight from the transmitting station, on a mountaintop repeater site, and it was the combination of both incidents over a period of a week that brought attention to the possibility of 'jamming'.