The invention provides a component selection control system comprising signal output components 2 to 5, signal input components 4, 5, and an amplifier unit 1 having these components 2 to 5 connected thereto. The third circuit is arranged to receive at least one of the first and second timing information, and further arranged to produce third timing information dependent on at least one of the first and second signals. A trim system is configured to selectively supply engagement and disengagement pressures to at least one fluid passageway. The method also includes calculating a short term energy of fax data subsequent to the fax indicator signal. The primary and secondary WAPs exchange information so that, in the event of a handoff, the required information has already been shared with the new WAP. The rear end of the frame is configured to be positioned rearward of a front of a shoulder of a user.