A teletext data separation apparatus has a slice level generating circuit including a slice timing control circuit, a control register, an adder and a divider. Each of the in vitro apparatus and the connecting cord section includes pads which are structured to be air tight and water tight, and connecting sections for bringing close upon facing each of the pads. The cross-correlation and subtraction steps are iterated until no useful signals remain to be extracted. The first integrated circuit being programmed and configured to respond to the request by outputting the access permissions and key identities to the second entity for use with the function without outputting the secret keys.