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I've got a 1 GB Micro SD card, and my existing maps are taking up 14.2MB, so it's over 90% empty. In MapSource when I click on a map using the Map Tool it turns pink and adds it to the Maps list on the left. When I click on my map nothing happens. Dan

I've created a custom map that MapSource will not let me select with the Map Tool for downloading to the GPSr. I can select my map Product, and it displays great in MapSource - it just won't let me choose it. I've made a few other maps, and they work fine and can be downloaded to my GPSr. The only difference with this one is the size - it is 11.9 MB. Is there a size limit for IMG files, or have I done something else wrong making the map? Thanks. Dan

First, it seems there is enough interest in map making, and it is a unique enough topic, to warrant its own sub forum here. That would help us find information without having to weed through the "GPS Units and Software" forum which has such a massive number of posts. I've had good results making my own topo maps, with elevation contours and hydrology. If I could include land cover it would just about be perfect. Is there any free / open source toolchain to get from the GeoTIFF raster file the USGS land cover exports, to something vector that GPSMapEdit can handle? I found a program, Vextractor, that is $99 but has a usable demo version. It will vectorize GeoTIFF and save to MIF (MapInfo Interchange), which GPSMapEdit can import. However, only the registered version of GPSMapEdit can import MIF. I will only make one or two maps of my local area, so I can't justify buying several pieces of software. If that's the case I'll just continue to do without the land cover. Dan

Is that a generic 12V to USB adapter, or is it a Garmin? The adapter has to convert to 5V, and if it is a cheap (or defective) adapter it may not be producing the proper voltage (or it may not be properly filtered). If it still doesn't work after all the suggestions above then try a different adapter. Dan

BTW, if you want to average an existing waypoint, the technique is a little different. Select the waypoint and pull up the detail screen. Hit Menu, then you'll see an option "Average Location". Dan

Here's one method of checking the GPSr that comes to mind. Find somewhere where you can go straight and level for as long as possible. Reset the GPSr odometer and create a waypoint when you start, then ride some distance (a mile would be great). When you stop create another waypoint. The distance between the waypoints should match the odometer reading, if not, the odometer reading is wrong. Now that would be a best case scenerio - the GPSr should be most accurate in a straight line where corners, curves and hills aren't cut. You should expert even worse accuracy of the odometer in real terrain. You can also compare the bike computer to the waypoint distances, and calibrate your bike computer accordingly. Basically, the GPSr odometer will accumulate errors - it has to add up the differences between many samples. The error between waypoints is never more than twice the GPSr accuracy, no matter how far apart they are (talking level ground of course). Dan

Create a new waypoint. At the bottom left of the screen you'll see a button "AVG", which will put the GPSr in averaging mode. Hold it steady for a while and let it do its thing. Dan

Is your 60CX's firmware (internal software) updated? When you buy a new GPSr the firmware is almost certainly out of date (same with many other types of consumer electronics). Dan

That circle should represent the accuracy. To verify, do the following: When on the Map screen pull up the menu and select "Data fields..." Select 2 Data Fields Pull up the menu, select "Change Data Fields" Change one of the fields to "Accuracy of the GPS" Compare the accuracy value to the size of the circle. You should find that they correspond. Dan

Yep, that was it. I set all the <time> fields to a more recent value in the GPX XML file, and now MapSource can send it fine. That's definitely a bug in MapSource. Dan

Okay, I have an idea why MapSource is crashing. It has to do with the Modification Date of the waypoint. There were several dates from 1983 and older (as old as 1969). When those are removed it worked. I like MapSource for this, because I can select all the waypoints at once and set their icon all with one step. Dan

That works, but I can't seem to get it configured the way I want. For BMs I want a flag instead of a Geocache chest icon. I also want the cache name for the waypoint, but it is using some arbitary numbering ("GC 1", "GC 2", etc). I also noticed that some of the waypoints I sent with MapSource did make it onto the GPSr, but not all of them. So it is crashing at a specific waypoint. Also, with MapSource I tried sending both the my GPSr, as well as directly to the SD card placed in my laptop. Dan

I have a eTrex Venture Cx. I have downloaded the NGS datasheet from the NGS site, and converted it to GPX format using bmgpx.exe. I open the gpx file in MapSource, and everything looks good. However when trying to upload to the device MapSource throws an exception and displays error information that can be submitted to Garmin. Is that the proper process to get the BMs into my GPSr? BTW, GpxSonar loads the GPX file fine on my PDA. Dan

Sorry to bump an old thread again. Someone mentioned this inexpensive detector. If you scroll to the bottom, you'll see this other detector listed for the exact same price of $39.99. It is a "nine function" detector compared to the first one, which is "five function". Has anyone used this other detector, and is it better (sensitivity, general usefulness) than the 5 function one? "Three-way metal finder has three separate audio signals for different metals." The one thing I see is it would be bulkier to pack up and haul, but it also looks like it would be a lot more comfortable if you were doing a lot of searching. Dan

I get 25 feet. The ACME Mapper reports 28 feet. Definitely not less than the 5.6 accuracy the GPSr stated. I asked this earlier in my mess of questions, but no-one answered. When a marker has an adjusted elevation or location, exactly how accurate is it? Within inches, feet, yards? Does the precision vary from marker to marker? Dan

I just found another, and my GPSr was within .8 feet of the elevation when I set it down on the marker. However after it set there a bit it started inching up foot by foot over the course of 100+ samples during averaging. It seems to me that when the GPSr is in motion the elevation is more accurate then when stationary, which is counterintuitive to the way the location value behaves. This is (finally) a location adjusted marker (FZ1351). The official location: N 36° 57.119 W 081° 05.148 (NAD 83) My GPSr location: N 36° 57.119 W 081° 05.153 It was reporting accuracy of +/- 5.6 ft. How much distance does .005 represent? Dan

This time I got 2368, and the value was floating up and down. Dan

Aha! I hadn't noticed that small button. I did a quick test, and the averaged results were the same as the "instant" results with +/- 14 ft accuracy. I'm sure in some cases it will make a difference. I did some experimenting to figure out how to display the location in a large font on this device, so it can be seen clearly in photographs. The only way I've found to achieve that is to go into the Trip Computer, specify Big Numbers, then change the data fields. I have Location, Elevation and Accuracy, and just those three fill the entire display, so it's nice and big. And just think, you wasted it on me! Dan

I noticed those. The HAM was because of a "HAM BARN" that used to be there. All the repeaters are up on mountains around here, but I'll run over and try to find these since they haven't been logged. 73s, Dan

I know with geocache logs it's inappropriate to post spoilers unencrypted. Is that true for benchmarks too? I'm putting in basic pieces of info, like where to park, or where the marker is located near more modern landmarks, and I'm curious if those types of things should be encrypted. My impression is that with markers it's a bit more down to business to try to make recoveries that haven't been done in decades, but I don't want to ruin it for others.

I just noticed on the topo map a BM within a few hundred yards of where I'm at right now, so I walked on over and found it. After I located it I looked up the designator online, and found its altitude is 2361.16 ft. My GPSr reported 2362. LOL FZ0721 Dan

No, it doesn't have a barometer. I have a Yaesu VX-7R handheld amateur radio that I can get a barometer module for, but I don't know how accurate it would be. I had simply assumed that the elevation would be as accurate as the location, but geometrically I can see why that isn't so. I don't need accurate elevations any more than any other casual GPS user, but it's very good to be aware about the accuracy issue. Dan

Thanks for the reply! So am I correct in understanding that the accuracy the GPS reports applies to location and not altitude? The smokestack at the knitting mill is still in good shape, but is not accessible. That property is for sale, and is fenced and gated. I don't even know who to ask to gain access, because no-one stays at the site. Maybe I can catch someone mowing sometime (they do keep it mowed nicely though!). I was planning on heading to the top of the mountain soon, hopefully today. There are a couple caches up there too I'd like to grab. I have heard a few mentions of "averaging" a location, and seen pictures of a GPS (Magellan I think) that was in some sort of averaging mode. My GPSr doesn't seem to have such a mode. If my GPS is reporting a good accuracy (like the +- 6 ft I got yesterday) am I correct in assuming it is really that accurate? Should I specify the accuracy the GPS is reporting when I log a marker location? At the post office I couldn't get better than +- 30 ft because the marker was against the side of the building. The railroad station marker was even worse, because it was under a roof and against the building. In cases like that do you try to get a reading out in the open, measure the distance to the marker, and translate the reading? Or is it simply not that important to be that accurate? Dan

Okay, I set out to find some local markers to get a feel for the accuracy of my GPSr (eTrex Venture Cx). All of them I've found so far have scaled location, so I can't compare that. However all of the altitudes are adjusted. The altitude my GPS reports has been off by at least 17 feet, and has been off both to the the positive and negative. The first marker listed below is the most concerning to me, because my GPSr was reporting an accuracy of +- 6 ft, yet it differs from the marker's entry by 17 feet. FZ0720 FZ0705 FZ0707 I'll probably run by a couple of these again today to see what my GPSr is reading now. Is this normal for GPSr? Adjusted altitudes should be extremely accurate, correct? As in what, within inches? Dan East

I have a Venture Cx (I don't know how it differs from the Venture HCx). It only has a simple national basemap (basically only interstates and state routes), and does not come with any PC software at all or a Micro SD card. I have built my own topographic maps (elevation contours and hydro), and uploaded from Garmin's MetroGuide for street level detail. Note that you can only place maps on a Micro SD card, and not directly in the device's internal memory. So you will have to buy a card if you want to expand the maps (2GB cards can be had for less than $30 including shipping at Amazon). Or you can buy a card preloaded with maps from Garmin. I've never used a automotive GPS before, but I can tell you that this unit's audio is very low, and it would be doubtful you could hear it beep to alert you during routing. I wouldn't want to risk relying on that to not miss a turn. Now if you want it for visual routing, then it would be fine. Dan