vhs-c adaptor

Home VHS Cassette VHS Camcorders VCR Basics		Video Cassette Tape VHS-C JVC's miniature VHS format, VHS-C, was launched in 1982.

		VHS-C cassettes use the same 1/2 inch tape as standard VHS, and the same recording format. The cassettes can be inserted into a full-sized cassette shaped adaptor, which allows them to be played back (or even recorded) in any normal VHS machine.

	A VHS-C cassette in its adaptor shell. When the lid is closed, motorized guide pins pull the tape out and across the front of the adaptor, and the shell's right-hand spool is linked by toothed wheel to the compact tape's spool. The combined tape then behaves just like a normal VHS cassette.
VHS-C cassettes were initially limited to 20 minutes, because there wasn't room for any more tape in the cassette. As plastics technology advanced, thinner tape became realistic and 30 minute VHS-C cassettes became the standard size - using 15 micron tape rather than the standard 20 micron. Later still, in 1990, 45 minute (90 min. EP) C-format cassettes appeared, using even thinner tape.

In order to make the machines as small as possible, a reduced-sized head drum was used, 41mm rather than full-sized VHS's 62mm. To keep the recorded signals compatible with VHS, four heads were used, with the tape wrapped three-quarters of the way around the drum, and the drum spinning at 1.5 times normal speed (2250 RPM rather than 1500). The four heads take turns writing: as head 1 completes its scan, head 2 has traveled 3/4 of the way around and so is ready to start the next field.