I believe that display unit is shown as a component of the Ekco E-120 weather radar system shown in this link -
https://www.radartutorial.eu/19.kart...rte076.en.html
Unfortunately detailed information on the Ekco radars is notoriously sparse on the internet.
I suspect the seller of the unit didn't know what it was.
A lot of avionic equipment is marked with a 'Compass Safe Distance', this is a minimum distance to avoid disturbing the operation of a compass sensor.
Andy