An efficient encoding method is provided for error correction coding in high density magnetic recordingreproducing apparatus. The method involves a two-pass physical placement technique. The timer is configured to track the useful life of the patient position pad. The intermediate sleeve engages and generally surrounds a portion of the ferrule holder back section and thus surrounds a portion of the buffered layer. The second signal has a substantially constant current and a second frequency distinctly higher than the first frequency. The microcrystalline silicon film is formed on the gate insulating film side and the silicon carbide film is formed on the wiring side.