icom 2820 + ut123 now what?

[m6rkw]

Ok so im a very recently passed uk foundation licence holder ( so my knowledge is limted, very)

Im interested in tracking this setup while in the car and using say aprs.fi ( well the mrs is)

The question is this, what else is needed for the setup to give the ability to track the vehicle while on the move? software for the pc back home? hardware if any for the car?

I have been reading this to death online but dont seem to be getting anywhere at all....

Any help on the setup gladly welcomed!

73s
Mark

 

[W5LZ]

Mark,
There are a couple of things you will need for your vehicle to do APRS. Those things are a transmitter to send the information (you have that), a GPS receiver which gathers the information about where you are, a device or method to encode that information from the GPS to send to the transmitter in the expected format, and an antenna to do all of that radiating, naturally.
There are several ways of doing all of the above. The 'best' for you would be whatever would be the simplest and most inexpensive, right? I would be a terrible judge of that, so I will tell you what I've done, and you go from there.
I use a 'stand-alone', small transmitter and GPS device. It doesn't involve my 2 meter radio at all. For various reasons I found this to be 'best' for my particular situation. (Primarily becasue I wouldn't tie-up the 2 meter radio, wouldn't have to reprogram it, and it was cheaper than my next alternative. It's not easy being this lazy and cheat, you know.) Go here and take a look at what's there;

Byonics -

The operator of the site is very helpful, doesn't mind questions at all.

On the receiving end, the simplest set up is a computer and a connection to the internet. From there, you can make it as complicated and/or expensive as you like. Why use the internet instead of receiving directly off the air? The number and distance from repeater stations, a separate set of receiver and decoding equipment, and knowing how to connect all that stuff together, is one pretty good reason. I've made that sound like it's sooo difficult, but I've done it, so it can't be all ~that~ difficult, right? (The internet APRS sites are seldom 'real time', the amount of 'lag' is very variable.)
You happen to be in the place where a lot of the APRS software has come from, so finding the right 'group' to get information from is just a matter of looking till you find it. I like "UI-View" and the associated stuff that goes with it. Not because it's the absolute best in the world, but because of the user interface (display and controls), and it's ~FREE~!! I've tried several different (non-free) programs which do all kinds of various thingys, but tend to come back to 'UI-View'. Don't read any more into that than I'm a slow learner, am comfortable with it, and because it does what I want it to do. There can certainly be programs better suited for you.
Since there were very few people around here that knew anything about APRS, I had to do a lot of 'looking' to find out the information I needed to get this stuff working. Made more mistakes than anyone would believe, and sort of learned by my self. All I can say is that it just takes a little time, and if I can do it, anyone can, and I wish that were modesty speaking!
Good luck.
- 'Doc

(This stuff get's sort of addictive so you might wanna remember that and seek help when necessary.)

 

[Moleculo]

One option is to purchase the D-RATS software, which I saw at Dayton this year. D-RATS expects to be connected to a DStar radio, but it might work with the DVDongle. You would probably have to email them to make sure.

There is a way to send APRS messages using DStar radios without needing an external TNC, assuming you're using the Icom GPS accessory (which you are). Please note that I have not done this myself, but I have read the basic instructions. These are copied from the official APRS website at www.aprs-is.net:

D-PRS


APRS-IS > D-PRS​

D-PRS InterfaceD-PRS Message Calculator
Description

D-PRS is the act of converting Icom GPS information generated by Icom D-STAR radios in GPS mode into TNC2 fomatted APRS strings. It is important to note that D-PRS is not a protocol but a conversion specification. D-STAR digital voice mode (DV mode) is a 4800 bps digital data stream with no error detection or correction. Each transmission consists of a RF header followed by a 4800 bps stream of bits. 3600 bps of this stream is dedicated to the AMBE encoded voice. The remaining 1200 bps is used for synchronization and user-defined capabilities. Icom made use of this user-defined space to pass radio messages (simple display messages) and to pass serial data.
There is about 900 bps available for the serial data. Icom saw an opportunity to incorporate GPS information into this serial data. The intent was to maintain the primary purpose of DV mode, sending voice, while providing a potentially valuable adjunct data stream, GPS information. I designed D-PRS to take this GPS information and make it presentable to the APRS world. D-PRS removes the need for designing special-purpose mapping software just for the unique Icom GPS data stream. Note that Icom's use of the data portion of the DV signal for GPS is an Icom implementation, not a D-STAR specification. The D-STAR specification designates the data "sub-channel" but does not dictate what is done with it.
Icom introduced a new GPS mode called GPS-A mode which is shorter in format and includes a CRC. I recommend using GPS-A mode on GPS-A capable radios as a CRC is more reliable than an XOR checksum and the likelihood of an error disrupting a single GPS-A line is less than the likelihood of interrupting 3 lines in GPS mode. A full description of D-PRS was delivered to the DCC conference in 2007 and can be found in the D-PRS white paper.
D-PRS Interface is a Windows GUI application that lets you run a mapping program locally and watch what is happening on your local frequency. Click here for more information on D-PRS Interface.
Radio Configuration - GPS Mode

Because there is no error detection or correction on the data sub-channel, D-PRS mandates a specific message format for radios running in GPS mode. This message must be the same as calculated on the D-PRS Calculator page.
Only the RMC and GGA GPS strings are used in GPS mode. Set your radio to only use those two GPS strings.
Radio Configuration - GPS-A Mode

Radios in GPS-A mode do not need to set their GPS message per the D-PRS Calculator page. Instead, they should set their UNPROTO to APInnn,DSTAR* Note that the first part which is commonly called the "unproto" or "destination" field is comprised of the APRS standard for Icom, API, followed by the first 3 digits of the radio model number. In the case of the handhelds (only 2 digits), you may optionally use the first character following the model number (92AD would be API92,DSTAR* or API92A,DSTAR*).

GPS-A Mode
UNPROTO Settings RadioUNPROTOIC-2820API282,DSTAR*IC-80API80,DSTAR*IC-92API92,DSTAR*ID-880API880,DSTAR*

Radio Configuration - All Modes

Radios should beacon no more often than every 5 minutes. If you are active on voice, turn beaconing off since everytime you transmit, GPS information is transmitted if GPS or GPS-A mode is on.
If you are within range a repeater, set your URCALL to CQCQCQ, RPT1 to the repeater call, and RPT2 to the gateway call (repeater call with "G" in the eighth position). This will allow your data stream to reach the gateway but prevent it from going any further. Most D-STAR repeaters now have D-PRS implemented on the gateway. You do not have to be registered with the gateway for this to work.

 

[m6rkw]

Thanks for all the info, it has been a great help.

I was under the impression that using the gps board built in to the icom 2820 and ut123 that, that would do the job ( track the car from home)..

for now no d star repeaters are setup in the area im in hence why i wanted to us aprs for now..

Must keep reading, this is getting complicated!

Thanks again guys..