An information signal recording and reproducing apparatus, including a recording arrangement for recording information signals, the recording arrangement including at least one rotary head obliquely tracing a tape-shaped recording medium, the information signals including four kinds of pilot signals...http://www.google.com.tw/patents/US5079650?utm_source=gb-gplus-share專利 US5079650 - Information signal recording and reproducing apparatus with a mark signal and four kinds of pilot signals
