Front view, right side

Picture courtesy of Henrik Clausen, Copenhagen

The GD/31 was originally used as direction-finder vehicle in the "DAISY"-system. The concept was based on high operational requirements, e.g. 100% mobile, manual and automatic direction finding in the frequency range 0.3 to 1300 MHz (control from a mission center), search mode with optional suppression of selected frequencies and operation at both spot frequencies and through frequency bands, demodulation of AM, FM, SSB and CW signals, high bearing accuracy (maximum error after calibration 2° RMS), access by up to three operators and protection against overvoltage (lightning).
DAISY consists of subsystems, each made up of three DF vehicles with trailers, an escort vehicle, also with trailer, and a mission center. The Danish Army initially used the shown vehicle, but after a few years switched over to all-terrain vehicles from MAN as a platform for the direction finders.