A Wireless Local Area Network supports multiple slot times. The toners include first and second toners of different colors. The low pass filter filters the high frequency components of the unfiltered local oscillating signals to generate a plurality of local oscillating signals having phase angles of 0\xb0, 30\xb0, 90\xb0, 120\xb0, 180\xb0, 210\xb0, 270\xb0 and 300\xb0, respectively. A parabolic dish reflector concentrates solar energy onto the inner surface of the heater element.