hum, i would try this, but my dish network box ran me 100 bucks, and i dont want to risk breaking it.
the reason the box may sustain long term damage is if you magnet the hard disk inside the box. magnetizing the hard disk will ruin all the programing on it, rendering your box useless. however some dont have disks, like the really old models.
easy way to tell if you have a disk = can you record tv shows? if so, then yes you have a disk.
but even if you had a disk box, i am sure you could just be really careful and only magnet the receiver and other parts. if i get some lead i may try to isolate the drive and try this.