Differentially correcting GPS data collected using MC5GPS data collectors

The old MC5GPS data collectors have built-in GPS engines that have outlived their preset GPS life.  This causes all the collection dates to be marked as December 1998 when you attempt to use PC-GPS to differentially correct the job data. There is no GPS firmware update available, but we have a fix for it.

Please download udate.zip from


The udate.exe program is a DOS program that you can run in Windows command mode.

It will let you change date in an .ftr file. You will need to know the date your data was collected.

Usage:        udate     <job file name>    <new job file name>

After running udate, make a copy of the files associated with the .ftr job file (*.def and *.raw) then change the job name to be the same as the above <new job file name>.

Then perform differential correction on the files with new job file name.


Many of our customers have moved on to collecting real-time GPS data by using our iCMTGIS PRO on an iPad or iPhone device  in conjunction with a SXBlue Platinum or EOS Arrow Gold high-precision GPS receiver.




Australian Datum DGA94 and MGA94 Projections

If you need to use the Map Grid of Australia based on the GDA 94 datum, you can define these as user-defined coordinate system and datum, respectively within your PC-GIS 9, PC-GPS 9, PC-MAPPER 9, PC-MAPPER AI 4, CMT-Forester 10, CMT-SURVEY 9 or COGOCAD 9 software program.

The Edit Datum and Edit Coordinate System buttons are available when you select “User Defined” under Map – Coordinate System.

The screen shots below show the parameters to enter for defining the GDA 94 datum and the MGA 94 Zone 55 projection.

How to move an existing Feature?

Generally we encourage you to record position data faithfully and not manipulate it besides applying GPS differential correction. Should you have a legitimate reason to move a Feature, there are a few ways to accomplish the task. If you plan to run differential correction on the data, then do not change the data before applying the differential correction. Changing the data will cause differential correction to fail.

1. Offset

In the Feature Properties screen that comes up when you double-click on a Point, Line or Area Feature, there is a “No Offset” button. After clicking on it, you can enter the offset information to displace the Feature. The “No Offset” button label will change to “With Offset”.

2. COGO – Translate

This function will move the selected Feature in one of three ways:

a) Move the Feature based on the displacement of one existing point relative to the location of another point.

b) Move the Feature by the XYZ adjustment you enter.

c) Move the Feature based on the displacement of one existing point to the location of a point for which you enter the exact coordinates.

In a) and c) above, you will need to add a Point at the node you wish to use as the Move Point. This function does not work on nodes.

3. Ctrl click

If you hold down the Ctrl key on your keyboard then click on a Feature, the Feature becomes “unhitched” from the map. Subsequently you will be able to drag it to any position in Map View. For a Line or Area Feature, you will also be able to drag any node to a new position and change the shape of the Line or Area.

Juniper Systems Mobile Connect

As you know, Microsoft stopped supporting Windows Mobile Device Center (WMDC) with the Windows 10 version 1703 update. In a previous post we mentioned a workaround and alternative file transfer methods. 7/5/17

Recently Juniper Systems announced a software program that provides an easier way to transfer files from a Windows Mobile device to a Windows 10 PC via USB.

You could test Mobile Connect with your Windows Mobile or Windows Embedded Handheld 6.5 device during the free 7-day trial that Juniper System offers to see if they are compatible.

After creating an inside buffer, what’s the remaining acreage?

Suppose you have created an inside buffer for an Area Feature. When you select the inside buffer and click on Measure Area, the pop up window will show the acreage of the “Excluded Area“, which is the remaining acreage of the original Area Feature.

Does PC-GIS produce Geo-reference PDF for use in Avenza?

Our apps do not generate nor work with geo-referenced PDF maps.

You could give this site a try:


Make sure you upload both the .tif file and the .twf file to the converter.
You could request a sample converted file first, which does not count toward your three free conversions.

Is there a way to tell that we have used the Offset function to move a feature?

When you double-click on a Feature, the Feature Properties window will pop up. If the Feature was offset, you will see a button labeled “With Offset“. Otherwise, that same button would be labeled “No Offset”.

Also, if a Point Feature has been offset, you can see its actual GPS location indicated by a tiny red node. To have the nodes displayed, click on the Display/Hide Nodes icon on the tool bar.