Electrode unit
From Tardis Wiki, the free Doctor Who reference
The electrode unit was a device which looked like a radar dish. It could operate electronic controls remotely. It was used in this manner by the Daleks, as an alternative manipulator arm to enter the Mechanoid City. (TV: The Chase)
Jo Grant, on behalf of the Third Doctor, requested an electrode unit from UNIT's scientific supplies section. (TV: Terror of the Autons)