Abstract: An in vivo rezero apparatus for a pressure transducer is disclosed. This invention includes embodiments where both sides of the pressure transducer are exposed to atmospheric pressure to rezero the pressure transducer and embodiments where both sides of the pressure transducer are exposed to physiologic pressure to rezero the pressure transducer.

Abstract: A system and methods are disclosed for monitoring a home TV viewing system which may include a TV, a VCR and one or more cable converters. The system obtains information for identifying the source of video displayed or being recorded, i.e., off-air antenna, satellite antenna, cable converter tuner, VCR, personal computer, video game, etc. The system also obtains information identifying the video path of the video being displayed and/or recorded. The system "fingerprints" video recorded by the VCR so that the played back video may be identified as having been previously recorded. The system may record the date and time of recording and the video source of the video being recorded. The system includes probe/detector devices which obtain signals related to the frequency to which the TV, VCR, and cable converter are tuned, and a higher level processor which receives and processes those signals to identify channel tuning of the TV, VCR, and cable converter.