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-inch Type E Helical Scan or SMPTE E is an analog recording videocassette format marketed by Sony, Matsushita Electric Industrial Co. (Panasonic) and JVC (JVC). It was initially developed by Sony and shown as a prototype in October 1969, refined and standardized among the three manufacturers in March 1970, and introduced commercially in September 1971 by Sony. The format was branded U-matic by Sony, U-Vision by Panasonic and U-VCR by JVC, referring to the U-shaped tape path as it threads around the video drum.
The format was among the earliest video formats to house videotape inside a cassette, replacing the reel-to-reel systems common at the time. The format uses tape, earning it the nickname "three-quarter-inch" or simply "three-quarter," in contrast to larger open-reel formats like Type C videotape and quadruplex videotape.
U-matic was named after the shape of the tape path when it was threaded around the helical scan video head drum, which resembles the letter U."After exhaustive research, the development team was confident it had devised a mechanism that could be used for cassette tape VCRs, the U-loading system. The name was derived from the U-shaped figure the tape followed when seen from above." Sony History, Sony:. Betamax uses a similar type of "B-load" as well. Recording time is limited to one hour. It initially had a resolution of 240 Television lines. Signals are recorded onto the tape using Frequency modulation (FM modulation).
U-matic tape moves at 3.75 inches per second, and has a tape writing speed of 8.54 meters per second for PAL or 10.26 for NTSC. This means that the heads on the drums of U-matic VCRs move across the tape at one of those speeds. The drum has two heads, both of which are used for recording video. The drum spins at 1500 rpm for PAL or 1800 rpm for NTSC.
Some of the standards that define the format, are:
PAL U-matic Hi-band increased the FM carrier frequency to 4.8-6.4 MHz. When recording it had a sync tip frequency of 4.8 MHz, a peak white frequency of 6.4 MHz, and a color carrier frequency of 983.803 kHz.
PAL U-matic Hi-band SP increased the FM carrier frequency further to 5.6-7.2 MHz, while increasing the color carrier frequency to 924 kHz.
U-matic Lo-band when recording NTSC has a sync tip frequency of 3.8 MHz, a peak white frequency of 5.4 MHz, and a color carrier frequency of 688.373 kHz. NTSC U-matic SP has a peak white frequency of 7 MHz.
When recording PAL, U-matic Hi-Band SP had a sync tip frequency of 5.6 MHz, and a peak white frequency of 7.2 MHz, retaining the color carrier frequency of regular Hi-band.
U-Matic saw even more success from the television broadcast industry in the mid-1970s, when a number of local TV stations and national TV networks used the format when its first portable model, the Sony VO-3800, was released in 1974. This model ushered in the era of ENG, or electronic news gathering, which eventually made obsolete the previous 16mm film cameras normally used for on-location television news gathering. Film required developing which took time, compared to the instantly available playback of videotape, making faster breaking news possible.
A smaller cassette officially known as U-Matic S, developed for use in portable recorders, acquired traditional double-flange reels, which reduced the amount of tape that could be loaded, and as such, the duration of recording. U-Matic S tapes had a maximum recording time of 20 minutes, and large ones 1-hour, although some tape manufacturers such as 3M came out with 30-minute S-tapes and 75-minute large cassettes (and DuPont even managed 90-minute tapes) by using a thinner tape. It was the U-Matic S-format decks that ushered in the beginning of ENG, or electronic news gathering. To minimize weight and bulk in the field, portable recorders had an external AC power supply, or could be operated from rechargeable nickel-cadmium batteries. S-format tapes could be played back in older top-loading standard U-Matic decks with the aid of an adapter (the KCA-1 from Sony) which fitted around an S-sized tape; newer front-loading machines can accept S-format tapes directly, as the tapes have a slot on the underside that rides along a tab.
The price of the VO family was primarily oriented toward educational, corporate and industrial fields, featured unbalanced audio connectors, and did not typically include SMPTE time code (although one or two companies offered after-market modification services to install longitudinal time code). The VO-3800 was largely metal, which made the unit heavy, but still technically portable. The VO-4800 had the same functionality as the VO-3800, but at a greatly reduced weight and size, by replacing many components with plastic. The VO-6800 added the improvement of a long, thin battery standard ("candy bars") that permitted storage of the batteries in a trouser pocket. Common model numbers for these batteries were NP-1, NP-1A and NP-1B. The VO-8800 was the last of the portable VO series to be produced by Sony, and featured solenoid-controlled transport.
The Sony BVU family (Broadcast Video U-matic) added longitudinal and vertical interval SMPTE time code, balanced audio , and heavier-duty transport features. The BVU-50 enabled recording in the field but not playback, and the BVU-100 permitted both recording and playback in the field. Portable recorders were connected to the camera with a multi-conductor cable terminated with multi-pin connectors on each end. The cable carried bi-directional audio, video, synchronisation, record on/off control, and power. Early studio and all portable U-Matic VCRs had a drawer-type mechanism which required the tape to be inserted, followed by manual closure of the drawer (a "top-loading" mechanism). Later studio VCRs accepted the cassette from a port opening and the cassette was pulled into and seated in the transport (a "front-loading" mechanism).
Some U-Matic VCRs could be controlled by external video editing controllers, such as the cuts-only Sony RM-440 for linear video editing systems. Sony and other manufacturers, such as Convergence, Calaway, and CMX Systems, produced A/B roll systems, which permitted two or more VCRs to be controlled and synchronised for video dissolves and other motion effects, integration of the character generator, audio controllers and digital video effects (DVE).
In 1976, Sony introduced the semi backwards-compatible High-band or Hi-band revision, with the introduction of the top-loading BVU-200. The original version became known as Low-band or Lo-band. U-matic Hi-band had an improved colour recording system and lower noise levels. BVU gained immense popularity in ENG and location programme-making, spelling the end of 16 mm film in everyday production. By the early 1990s, Sony's Betacam SP format had all but replaced BVU outside of corporate and budget programme making. With BVU-870, Sony made a final revision to U-matic, by further improving the recording system and giving it the same "SP" suffix as Betacam. SP had a horizontal resolution of 330 lines. The BVU-800 series Y-FM carrier frequency was upped to 1.2 MHz giving it wider bandwidth. The BVU-800 series also added Dolby audio noise reduction. Sony's BVU-900 series were the last broadcast U-matic VTRs made by Sony. First-generation U-matic SP and Beta-SP recordings were hard to tell apart, but despite this the writing was on the wall for U-matic, due to intrinsic problems with the format.
The format video image also suffered from head-switching noise, a distortion of the image in which a section of video at the bottom of the video frame would be horizontally askew from the larger portion.
The format also had difficulties with reproducing the red color on the NTSC color standard, and red images would be noisier than other colors in the spectrum. For this reason, on-camera talent was discouraged from wearing red clothing that would call attention to technical shortcomings.
Copying video from one U-matic VCR to another compromised playback reliability, and levels of head-switching noise, chrominance smearing, and chroma noise compounded with every generation. These issues motivated videotape editors and engineers to use work-arounds to minimise this degradation. A time-base corrector (TBC) could be used to regenerate the sync tip portion of the video signal sent to the "recording" VCR, improving playback reliability. The "dub" cable, more formally called "demodulated" (or "demod" for short), was a multi-conductor cable that circumvented a portion of the video circuitry, minimising amplification noise.
U-matic tapes were also used for easy transport of filmed scenes for dailies in the days before VHS, DVD, and portable hard drives. Several movies have surviving copies in this form. The first rough cut of Apocalypse Now, for example (the raw version of what became Apocalypse Now Redux), survived on three U-Matic cassettes.
Audio quality was compromised due to the use of longitudinal audio tape heads in combination with slow tape speed. Sony eventually implemented Dolby noise reduction circuitry (using Dolby C) to improve audio fidelity.
The 2012 film No, set in 1980s Chile, used U-matic tape for filming.
Many television facilities the world over still have a U-matic recorder for archive playback of material recorded in the 1970s and 1980s. For example, the US Library of Congress facility in Culpeper, Virginia, holds thousands of titles on U-matic video as a means of providing access copies and proof for copyright deposit of old television broadcasts and films.
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