GPS

My Current GPS Setup

Garmin eMap with firmware 2.62
External battery pack, 8 AAs for the eMap
Palm III to store longer tracks
GPilotS software, used on the Palm to download from the eMap and upload to the PC.
G7ToWin software, used on the PC to interface with the Palm III and the eMap and StreetAtlas. It is also used as the master program. It stores and modify the tracks and waypoints.
DeLorme StreetAtlas 7 software, used to map the tracks and waypoints
Interface Cables, I made my own interface cables, the connectors can be purchased from PFranc.

2004 Season

Well I'm starting to thinking about making some changes.

Power the eMap from the snowmobile:
I'm revisiting the power regulator that I made a few years back. I still think the regulator is sound and needs some testing in a control environment. Some initial testing showed that the LM317 would over with a 225 mw load on it. I accidentally touched the LM317T and burned my fingers. The eMap will draw at least 325 mw with the back light on. So I have no heat sink to dissipate the heat. I made up a heat sink, four thin pieces of aluminum bolted to the LM317T, about 1/2" by 3" that come through the case and then fans out. I may need to add more fins. I have tested it with 30 vdc in. I will need to test up to 40 vac. Although, the ac on a snowmobile engine is not the same as the ac coming out of the wall. 1000 to 8000 Hertz verses 60 Hertz. I'm going to retest the filtering part of the circuit and make sure there is clean DC coming out and no excessive ring.

Mounting system:
I have been using Velcro to hold the gps down to the dash. The problem with this, is on the old sled you could only see the screen when standing up. The new sled is less friendly, the dash is slanted forward and make seeing the screen more difficult. I decided to put the Velcro on the vertical part of the dash. This was not the best idea. The Velcro was not strong enough to hold the weight of the eMap and the battery pack while going through the heavy stuff. I all most lost my GPS. I have a RAM mount that I use on my 4-wheeler and will start to use it once on have start using the power regulator.

Stay tune I'll have some circuit diagrams and pictures when I'm done.

2001 - 2003 Seasons

No major changes for these two seasons. I continue to use the external battery pack. I could get a full days ride without worrying about the batteries running down. I also continued to use the Palm III to save the tracks out to when the logs got full. The log seem to fill at around 100 miles.

2000-2001 Season Trials and Errors

   Well, I now have another snowmobile season using my GPS under my belt. I'm real happy with the way it turned out. I tried a few new things. The first I would highly recommend
   The Garmin II+ I use to have developed many small scratches on the screen. At the beginning of last season invested in the clear plastic protectors for palm pilot screens. They did not stay on very long. I discovered clear packing tape would do the trick. Put it on, rub the bubbles out and cut it to size with an exactto knife. It save the screen from getting many scratches. I just removed the tape a week ago to put on a new piece. There was a lot residue left but a little mineral sprits and some q-tip took care of it.
   The eMap did not work as well as the II+ in my pocket. I bought a 2" x 4" piece of velcro from Wal-Mart and secured it on the dash of the sled. It didn't go anywhere all season long. It was easy to attached and remove. It was a lot cheaper than the Ram-Mount.
   The one thing that did not go as well as I had hoped for was running the GPS off the sled power. I built a power regulator with a 3 volt DC power output. I thought it was working but, at times when I look down at the eMap, I would find it powered off. I'm not sure if it was from getting to much power or not enough, either the circuitry was not producing the power or a bad connection. I was not interested in frying the eMap so, I ended up purchasing 4 new NiMH 1600mhr AA batteries and a fast charger. Usually 4 batteries would do for the day. If I need to recharge, the barmaids didn't mind plugging my charger in for me.
   I'm going to stick with using rechargeable batteries this year. To get long run times with out swapping out batteries, I purchase 4 enclosed battery holders that holds 2 - AA batteries each (Radio Shack 27-408). The holders are wired in series and then I wired each holder to the other in parallel. I used model glue to secure them together then placed one piece of velcro across the top and the other haft of the velcro across the bottom of all four holder. I attached a PFranc connector the lead coming out for the battery pack to connect to the eMap. Now this battery pack will velcro to the GPS and then the hole unit will velcro to the sled. I was hoping to go with 2 or 4 D cells which would have much longer life, 8000mhr -vs- 1600mhr per cell but, I was not able to find an enclosed battery holder. I would also have to purchase a new charger for the D-cells. I will tell you how it goes.
   The other problem I ran into last year was the track logs over writing themselves. I now have an old Palm III that I can now download the tracks to while on the trail. Using a palm cable cut a 1/3 off the palm end (about a 1 ½ feet) and attached the PFranc (http://www.pfranc.com/) connector at the end. The other 2/3 of the cable is used to connect the GPS to the serial port of the PC, using a second PFranc connector. I use GPilotS (http://www.cru.fr/perso/cc/GPilotS/) on the palm to upload to. Then when I get home I will upload the palm and eMap to my PC using G7ToWin. The only problem with GPitolS is that you will loose the altitude data.
   Click here to see some of the maps I have made with my GPS. If you want a file with the waypoints and tracks send me an e-mail.

1997 to 2000 Seasons

There has been a few set backs and successes. I started with a DeLorme Earthmate, what a waste of money and time. Definitely not for outdoors use. I had to hook it to a PC or a Palm Pilot. The cable would always disconnect and the Palm and GPS would both suck the life out of the batteries The only thing that I like was the Street Atlas software that came with the GPS. I then purchased the Garmin II+ a year ago. I used it all winter long. I had no problems with it, but I did wish it had a more memory and a map base like the III+ did. I made a cable to connect to my PC's serial port. The cable worked great and saved me $30 dollars, one serial cable, three female connector pins from Radio Shack and a hot glue gun.
I ended up trading the GPS and $200 for a one year old galvanized 2 place trailer. I now have a Garmin eMap. I pick it up on clearance at Service Merchandise. The eMap has more memory to store longer tracks. It also has a small map base built into it and with the additional memory modules you can download more details maps using Garmin's Map Source software. Making a cable for this GPS is not as easy as the II+, but after three tries I think I got one that will work. I will post the direction on how to make one soon. If you get one of these make sure you upgrade the ROM on it to at least version 2.5. The only thing I'm not sure of is the eMap is not water proof. Time will tell if it will hole up to the snow this winter, may a water proof bag. Click here to see some of the maps I have made with my GPS.

Here is some of information that I found that was useful.

Here is a list of great resources on GPS's, I always start a one of these sites.

Joe Mehaffey: http://joe.mehaffey.com
Peter Bennett: http://www.vancouver-webpages.com/peter/
Karen http://www.gpsy.com/gpsinfo/
Dale DePriest: http://users.cwnet.com/dalede

Here are some software that I found to work well.

Waypoint+for Garmin Receivers.
OziExplorer GPS Mapping Software.
G7TO Up/Downloads for Garmin.

Aerial Photos, Satellite Photos and Topo Maps around the world

TerraServer Homepage (Microsoft)
TerraServer.com