EasyWeather Format
Many of the entry level weather stations can be classified as "EasyWeather" or "FineOffset"; they are rebadged or generic models of the device produced by FineOffSet Electronics
The software shipped with the device is EasyWeather and while it peforms its role of reading and storing data from the weather station, it is quite limiting and inflexible.
Of course, most users switch to Cumulus and stop using EasyWeather.
Simply for reference, below are some useful technical links on the EasyWeather format
The File Format
Easy weather stores all its data in easyweather.dat. The file format for this has been described in detail here
Memory Map
This page describes in some detail the data records produced by the Fine Offset device
Thanks to Jim Easterbrook for all his work on pulling this data together http://www.jim-easterbrook.me.uk/