A slot antenna for receiving and/or transmitting a RF signal at a desired one of a plurality of different frequencies. The slot antenna includes at least one conductive sheet having a slot defined therein, the slot being longer than it is wide and having at least one end which is open. A plurality of switch members are mounted along said slot close to the open end thereof, each of said plurality of switch members acting, when closed, to couple the at least one conductive sheet on one side of said slot to the at least one conductive sheet on a second side thereof. A feed point is provided for adjacent said slot. The plurality of switch members are closable in a controlled manner to change a desired resonance frequency at which the slot antenna receives and/or transmits the RF signal.