vehicle gps info

mokena208 · Post by **mokena208** » Thu Jan 26, 2006 6:44 pm

So I am not sure if this should be in the computer or vehicle off topic, but here goes.... I am looking for a good, reasonable gps system for 2 vehicles. One will be the EMA chief car. He has got a new dell laptop with vehicle mount and wants to be able to punch in an adress and get reasonably accurate directions. The other is for the new command vehicle. Similar setup, we want to be able to punch in the address and have help getting to the scene.

I have seen lots of gps NMO style antennas and software, but what is the interconnect? Also, I have seen things like Garmin software/hardware combos and the Microsoft Streets with GPS antenna.

I am sure that someone out in radio land has tired to do this. I would greatly appreciate any help!

Thanks

kb0nly · Post by **kb0nly** » Thu Jan 26, 2006 7:58 pm

Indeed they have, and i have personally! Check out the link for a full description and photos of my mobile setup.

http://batboard.batlabs.com/viewtopic.p ... hlight=van

With the laptop and vehicle mount your already half way there! I used the Sandpiper II GPS module, they run for about $25 shipped from ebay and have a SMA connector for the antenna. I bought a high frequency NMO mount with SMA connector installed from Waltel.com and the antenna was an ebay purchase but brand new from a dealer's store.

All together, around $70 in parts, rough estimate i don't remember the exact numbers.

There is some advantages to the Sandpiper module i used compared to other receivers. First of all low cost, second of all low power consumption, less than an amp at 5v even with the active powered antenna, and finally it has a seperate battery backup connection that only requires 2-5v, i tested it with a two cell AA battery holder and the draw is so tiny they would last forever, on the order of 10-15uA. This keeps the GPS receiver data when you shut off the power to it, so the next time you need it the lock time will be less. Though this module with a cold boot, from off to 3d lock, on average for me takes about 45 seconds.

Most of the USB receivers that i have tried take forever to lock, well it seems like forever when you need to be going down the road instead of waiting for a lock.

The software i use is Iguidance. It's made for quick and easy searching, you can load in just the state, or states that you need to narrow the data it needs to go through, and has a really fast user interface. Once it's set to your default state you just type the first letter or two of the city and then the street address, it will give best guesses on partial address's, etc. I think there is also a way through advanced editing of the user files to set a default city just in case your only concerned with one specific area.

ANB_Medic · Post by **ANB_Medic** » Thu Jan 26, 2006 8:54 pm

I use Microsoft Streets and Trips and would never consider changing. Certainly not going to knock kb0nly's suggestion though, as I have never used that setup. S&S comes with a USB receiver that you can tape to the dash. There was some discussion over in the lounge recently regarding it.

http://www.batlounge.us/viewtopic.php?t=1234

Todd

kb0nly · Post by **kb0nly** » Thu Jan 26, 2006 9:29 pm

Streets and Trips is ok, but around here its so out of date it's not even funny. Well... It is kinda funny to be driving along and seeing the pointer being out in the middle of nowhere. I guess they must not keep up with the latest changes in rural america.

I know they are accurate in larger cities around here.

60A · Post by **60A** » Fri Jan 27, 2006 9:23 am

I have a Garmin GPS 18, found at amazon http://www.amazon.com/gp/product/B0002H ... oding=UTF8 . Personally, I love it. It's some of the best money I have spent. For the most part Nroute and City Select are up to date. There have been a few instances where I went to someplace that was newer then the maps, but its rare. I'm using it on my Fujitsu lifebook b series which, while not as durable as a tough book... still makes a great mdt

.

mokena208 · Post by **mokena208** » Sat Jan 28, 2006 10:46 am

Wow guys! Thanks for the input. I had been looking at the garmin unit but was unsure about the usb type antenna. I will have to explore some of the other suggestions that were made.

Again, thanks to all!

mokena208 · Post by **mokena208** » Mon Feb 20, 2006 7:30 pm

Quick update.... so I went out and got two copies of Microsoft Streets and Trips 2006 with the USB GPS puck. One for the chiefs car and one for the command post. I have been playing around with the one in the chiefs car and have not had any luck getting the gps 'puck' to find its location. I will admit that I am new to this technology, but am I missing something? I put the 'puck' on the dash board and let it sit for about 20 minutes. The program kept trying to find the satellites but no luck. The vehicle is a 2000 Chevy Tahoe. Any tips? As always, thanks in advance for any help!!

kb0nly · Post by **kb0nly** » Mon Feb 20, 2006 7:56 pm

That's one problem with those, getting a good signal. If your only holding one or two satellites your not going to get even a 2d lock with it.

Try setting it up as close to the base of the windshield that you can get it, and make sure the vehicle is sitting in a relatively clear area, clear view of the sky that is. And see if you can get an accurate lock.

mokena208 · Post by **mokena208** » Mon Feb 20, 2006 7:58 pm

Thanks for the info. I had it more towards the rear of the dash. Would it make a difference if you are near a building/garage as opposed to an open field?

kb0nly · Post by **kb0nly** » Mon Feb 20, 2006 8:02 pm

It can make a difference between getting a solid lock and not getting one. If your on the opposite side of the building than the satellite is and the building height is enough to block the signal, then yes.

I have very little urban signal problems around here, but in a large city i have noticed the loss of a satellite or two, so that's why it's so important to hold as many as possible.

apco25 · Post by **apco25** » Mon Feb 20, 2006 10:21 pm

For good GPS covage you need....

1. decent clear view of the sky. GPS sats are usually low on the horizon due to orbit. You need at least 4 or more to get a stable 3-D lock.

2. Gain is good, more you have the better. GPS sats output a MINUTE amount of RF and its a hell of a long way away. High gain NMO type hockey puck on the roof will give you phenominal results. I've also had fantastic results using an interior glass mount antenna from mobile mark mounted in a corner of the front windshield. Gain is 29DB and performs as well as my roof mounted antenex NMO puck. Many of the cheap mag mount type mini antennas just don't perform well.

3. Stable receiver. I've gone through several types of receivers including several of the small chipsets from trimble like the ACE III, SIRF and Rockwell types. These are nice tiny units that do require a bit of build out to get them running.

However, I've found the older Garmin GPS II, III, III+ and GPS V (next to the last of their traditional style mobile GPS along with the streetpilots) to be nearly instant on cold or hot signal lock compared to just about anything else. They can be left powered up constantly with negligable amp draw (I leave mine on 24/7 and its under the ignition off amp load on the truck). They are also multi-format output capable such NMEA or garmin protocols, offer serial output (many new GPS units don't or offer USB only) and have the nice benefit of a display for routing without the laptop hooked up.

Precision Mapping (PM7) V7 is also an excellent program.

mokena208 · Post by **mokena208** » Tue Feb 21, 2006 5:15 am

thanks for the tips. Perhaps I should have gone the nmo route instead of trying to cheap-out and use the Microsoft mini puck. I will try a different location, but I suspect that I will be upgrading the receiver.

Thanks