Using GPS

[orion_jb2001]

Hi,

I am just about to delve into the world of GPS location scanning. I have and Australian UBCD396XT, but I am sure both the BCD and UBCD operate the same with GPS. Just waiting for the GPS receiver to arrive and I am currently updating my files to include the GPS locations etc. Whilst the different manuals explain it fairly well, just some questions about running GPS based scanning.

When currently travelling, I have systems and groups arranged geographically, selecting the relevant channels etc, as I go. (What a blessing the gps receiver is going to be!!!!!). Now for a particular route, I might set up 4 systems, to cover the relevant geography. Now with GPS assisted scanning, can I put all those systems into one system, relying on the GPS location to trigger the relevant sites etc, there is no need, with such a system, to isolate different areas from each other?

I also note, that with P25 systems, you can further break up your TGID's into relevant geographic areas, associated with a GPS "centre", again to trigger those TGID's when in range. Again, whilst I have all the relevant TGID's loaded for a particular service, presently, I lock up the non relevant areas, only to unlock them as required. Thus with such a GPS system, am I correct to assume that I could leave all the TGID's unlocked, relying on the GPS to trigger as appropriately.

Leading on from that, if as I think, I can currently combine separate systems into one relying on the GPS and also with TGID's etc for a relevant route, . How does this affect the running of the unit, where as now, there are only relevant systems, groups, TGID's or conventional channels active, to having say, everything active, does the GPS interface control the scanning to only scan those relevant systems, TGID's etc that are within range or does unit scan everything and only make available that that is in range?

Any suggestions or points to relevant posts etc, on how to use a scanner that is incorporating GPS location and the best way to set it up and use it.

Many thanks in advance for you reply's,

Jeff

 

[frazpo]

Can I put all those systems into one system, relying on the GPS location to trigger the relevant sites etc, there is no need, with such a system, to isolate different areas from each other?

Ive read your post and I do GPS scanning. Just to clarify about the above sentence. Are you speaking of "Quick keys" when you say putting systems in systems?

 

[orion_jb2001]

For a particular route, I use system site quick keys associated to conventional systems, to break up the geography of the journey, say 4 quick keys. So I could put the data that used to be in 4 quick keys/conventional systems, into 1 system, using GPS feature. With P25,again, I might group a number of neighbouring sites together, under 1 quick key, with say 4 different area, with 4 different quick keys for the sites.

Jeff

 

[frazpo]

For a particular route, I use system site quick keys associated to conventional systems, to break up the geography of the journey, say 4 quick keys. So I could put what use to be in 4 quick keys/conventional systems, into 1, using GPS feature. With P25,again, I might group a number of neighbouring sites together, under 1 quick key, with say 4 different area, with 4 different quick keys for the sites.
Jeff

I personally do not mix conventional sites with trunked sites under the same quick keys. But that is your choice. There is no problem with that. However I do group multiple sites under one QK. I do this with both Conv and trunked sites (seperately). This works well with GPS because it will do all the locking and unlocking automatically as you travel. You can simply activate the quick keys for a particular area or stretch of road and let the scanner do all the work. I think you have the right idea. Grouping them together will help automate everything and require less from you as you travel. Keep the QK grouping at a minimum though. When you connect your GPS it will start locking and unlocking the channels for that Geo area. If you have bunch of sites under one quick key then it will be that much more the scanner has to lock out on the initial startup. Its no big deal and the scanner will still scan as it does its lock/unlocking of sites and systems.

 

[orion_jb2001]

Thanks for that. No, I don't group conventional and trunked sites, under the same quick key, sorry if it read that way. So group conventional and trunked under a respective 1 quick keys with all entries unlocked and let the gps do all the clicking... lol .

Jeff

 

[ttrainor]

I've been using a gps-controlled 396XT lately and I'm loving it. It works as you expected -- just leave all the quick keys enabled and let the scanner choose what's in range. I don't even have any quick keys assigned. It only takes the scanner a couple seconds to do the initial lockouts once gps is acquired (my scan list is not huge, though)

It's a shame the FreeScan map plotter is broken, but you can use a site like http://www.gpsvisualizer.com/calculators#range_rings or http://obeattie.github.io/gmaps-radius/ to visualize your coverage.

 

[orion_jb2001]

Hi,

Thanks for the reply. Talk about .............as I am plotting locations and distances, I am thinking to myself and using little rulers over google maps, "wouldn't it be nice to be able to draw a circle based on your coordinate to see what the coverage is...."

that little program is brilliant, exactly what you need for such plotting !!!!!!!!!!!

Jeff

 

[orion_jb2001]

Another question. What happens if you have your systems and groups GPS enabled etc, what happens if you don't have a gps connected or you loose gps signal for what ever reason?? Does the radio stay in its last mode when connected to the gps, what ever is locked, remains locked, what ever was unlocked remains unlocked etc.....

Jeff

 

[orion_jb2001]

Units arrived and I have answered my last question. What an amazing piece of technology the 396XT is with GPS enabled!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Made up a little null modem cable with no issues at all.

Went for a little drive, where I know 2 P25 bases start and stop and the unit seamlessly swapped over between the 2, locking out and unlocking. Love the little tone and screen display as the unit locks out or unlocks the relevant systems/group as you drive. Takes a bit of programming to set up your groups etc, but after that, set and forget driving and scanning. Simply amazing

 

[orion_jb2001]

Some more questions, oh and so far, it is going great. When the unit is disconnected from the GPS, on reconnecting, does it go through the same lock out process or does it remember where it was and what has been previously locked out?

A question on systems and groups. I monitor 3 services through P25 network, Ambulance (EMS), metropolitan fire brigades and rural fire brigades. Now for simplicity (or may be not) I have organised 3 P25 systems, all with the same sites and then allocated one of the monitored services to each system. Each site is GPS enabled and each relevant service TGID is gps enabled to each relevant geographic area. I can not put all the groups under one system, due to the 20 group limit (there would be about 30 groups or so), so I can control what service I want to listen to by the relevant system key I have allocated each service and corresponding system. This works well, with only one system quick key needing to be pressed, to activate the required system, but, as there are 3 identical base systems with the same sites on each, does the unit have to scroll through each system and then lock out the sites not in range OR once a site has been locked out in 1 system, it will be locked out in the other 2 as well??

Now I have also created 1 system, with the relevant P25 sites and some arranging between the 3 services, to get under the 20 group limit (joining nearby areas together). It works but, each service has been allocated a group key and to activate the needed service, I first press the system key for this P25 service, then press the function key and then relevant group key for the service required (I want the end product to be able to lock out or unlock a service that I want to listen to, not grouping the 3 services together under a common geographical location, the gps service does that for me). When compared to the first setup, more key presses to get to the desire result, but less sites to lock out etc.

So my question, in a setup with 3 systems, all with the same sites, does the unit lockout or unlock a site and then have to do the same for the next 2 systems, or once locked out in one system, it also automatically locks out the same site in the other systems??

Jeff

 

[ttrainor]

1. The scanner will remain in the state it was in when gps was disconnected/ lost signal. Upon reaquiring gps, it will perform lock/unlock based on your new coordinates. You would have to power cycle the scanner or manually unlock each previously locked-out site/group.

2. I'm still a bit of a noob and have no experience with P25 systems, but it sounds like you ought to have one system, with however many sites (each with coords/range) and then put what you are calling services into groups (with the coords/range of the areas they serve). The TGIDs (channels) that each service uses goes under the group (and can't be gps controlled). If your services are broken down into different dispatch districts, you could set up each district as a group with its own coords. They can all share the same quick key if you want. Have I understood your set up correctly?

This should keep you under the group limit and speed up your scanning rate by not having to scan the same sites multiple times.

3. I think the lockouts would be repeated for each redundant site as they are considered different "objects" in the scanner's memory. The gps lockout is less of a problem IMO than scanning the same site multiple times.

 

[orion_jb2001]

1. The scanner will remain in the state it was in when gps was disconnected/ lost signal. Upon reaquiring gps, it will perform lock/unlock based on your new coordinates. You would have to power cycle the scanner or manually unlock each previously locked-out site/group.

2. I'm still a bit of a noob and have no experience with P25 systems, but it sounds like you ought to have one system, with however many sites (each with coords/range) and then put what you are calling services into groups (with the coords/range of the areas they serve). The TGIDs (channels) that each service uses goes under the group (and can't be gps controlled). If your services are broken down into different dispatch districts, you could set up each district as a group with its own coords. They can all share the same quick key if you want. Have I understood your set up correctly?

This should keep you under the group limit and speed up your scanning rate by not having to scan the same sites multiple times.

3. I think the lockouts would be repeated for each redundant site as they are considered different "objects" in the scanner's memory. The gps lockout is less of a problem IMO than scanning the same site multiple times.

So...

1: If you power down, all the lock outs will be come available and thus a new lockout scan would commence on powering up. if power remains on, just a re scan at new position, which if only a bit down the road, will be basically the same as before loosing GPs.

2. Yes you are reading this right and having just one system with the relevant sites would be less scanning. But in putting the different services into specific groups, you do have more keystrokes to undertake to activate the relevant group, function then the qk, and function key not the easiest to get to if driving where as a numeral key on the front is pretty easy to select., so having each service in its own system, with only 1 system quick key to activate or silence the service/group, is an easier and safer driving system I think.

3: That would seem correct. I think any lag with it processing 3 x systems with the same sites, will only occur at start up but I see the scanner will still scan and open up any channel whilst this lock out phase completes, so no loss of comms. Once travelling, locking out a site or TGID and opening up the next ones will be pretty seamless. I have only tried this set up whilst at home but an extended trip on Tuesday will test it out. Especially with GPS enabled sites and TGIDs, it makes it so much easier, just a little bit more complicated in setting up the system this way to lock or unlock specific services instead of having them all tied into a geographic point.

One not so funny set up problem discovered, I have used Freescan and ARC XT pro to do the programing. The P25 sites all have a published range, in miles, of 25. I had a TGID that was locking out, that should have been in range. Further careful investigating worked out that frees scan will only program in imperial measures (fine with 25 mille as the range) but not so fine if you have set up your GPS data in the 396XT to a metric unit of measure (now that would explain why the TGID was "locking out"). Oh well, it wasn't too much problem changing all the ranges from 25 miles to 40 kilometres and the TGID ranges from imperial to metric distances ........lol. Word to the wise, the 396 will treat what ever figure for range entered according to the unit of measure you set the gps default to.....

Jeff