Continuing from my previous post on Tracking Your Journey: I have chosen to alter the base settings of the AMOD to achieve much greater storage capacity and to fit the particular type of travel that I do. For example, on my safaris trips I have selected to turn OFF elevation since we will either in the air or on the road. Should I need ground elevation information, I can consult a map. I have also decreased the frequency of write times to the device. So, here are my settings and what they mean as far as the type of data that will be returned on the ‘write’ to the log: Mode 6, RMC logged at 10 second intervals. The National Marine Electronics Association (NMEA) has developed a set of specifications that defines the interface between various pieces of marine electronic equipment. The standard permits marine electronics to send information to computers and to other marine equipment. Most GPS manufactures have adopted the NMEA standard for recording GPS data and outputting the in a uniform manner. The most common, and considered the bare minimum, GPS data is RMC. RMC, as defined by NMEA sentence structure, returns a log that contains the following data for every log event:
RMC Recommended Minimum sentence C
123519 Fix taken at 12:35:19 UTC
A Status A=active or V=Void.
4807.038,N Latitude 48 deg 07.038′ N
01131.000,E Longitude 11 deg 31.000′ E
022.4 Speed over the ground in knots
084.4 Track angle in degrees True
230394 Date – 23rd of March 1994
003.1,W Magnetic Variation
*6A The checksum data, always begins with *
Using RMC as the minimum recording in Mode 6, I can record more than 2880 hours of data with more than 1,040,000 data points. In this configuration, each log is written to the device every 10 seconds – plenty for a land safari. The next post will walk you through down loading and processing for display on Google Earth.
Cheers and happy photo’ing