Tractor

This usually takes the form of a toothed gear that meshes with holes punched near the edge of the paper, or a belt or wheel with rubber or other high-friction surface that makes contact with the paper.
. A tractor is also the part of a computer printer that pulls paper into the device or pushes it along. However, Tivos and DVRs are the main competitors with the VHS in home recording. NASA and other space agencies use very large tractors to ferry launch vehicles like booster rockets and space shuttles from their hangars to (and in rare cases, from) the launchpad. It can also be more convenient to use VHS tapes because they can be rewritten easily, and VCRs can be easier than DVD recorders to use. Conversely, if to the rear, it is a called a pusher configuration. Despite DVD's better quality, however, VHS is still widely used in home recording of television programs, due to the large installed base and the lower cost of VHS recorders.

In aircraft, a tractor configuration refers to the propellers being in front of the fuselage or wing. Commentators predict that 2006 will be the final year of new releases on VHS, as major studios continue to phase out VHS. The term tractor or tractor unit (UK) is also applied to:. Moreover, most television programs released as box sets are for sale in DVD format only. Volvo Duett was for a long time the primary choice for conversion to an EPA or A tractor, but since supply have since dried up other cars have been used, in most cases a Volvo. Many films released to theaters from 2004 onwards have later been released only on DVD and not on VHS, and many other new feature films are being released solely on DVD. This is usually done by fitting two gearboxes in a row and not using one of them. retailers Circuit City and Best Buy stopped selling VHS tapes in 2002 and 2003, respectively.

The main difference is that an A tractor has a top speed of 30 km/h. Major U.S. In March 31, 1975 a similar type of vehicle was introduced, the A tractor [from arbetstraktor (work tractor)]. The DVD format was introduced in 1997 and has since overtaken VHS in sales and rentals. Eventually the legal loophole was closed and no new EPA tractors were allowed to be made, but the remaining were still legal, something that led to inflated prices and many protests who people that prefered EPA tractors to ordinary cars. In addition, it offers superior audiovisual quality, and the storage of data in digital format on tape makes for improved transfer and editing. Since it was legally seen as a tractor it could be driven from 16 years of age and only required a tractor license. MiniDV has largely replaced 8mm tapes as the de facto camcorder standard in more recent years as it is smaller still (some MiniDV camcorders being no larger than one's hand).

After the war it remained popular, now not as a farm vehicle, but as a way for young people without a driver's license to own something similar to a car. 8mm tapes, introduced in the early 1980s, succeeded as a format for camcorders (both in the consumer, and to an extent, professional market), as VHS and Betamax camcorders were unsuitably large and heavy in comparison. When done to an older car with a ladder frame, the result was not dissimilar to a tractor and could be used as one. As these cassettes are much more compact in design — which also means the hardware to play and record the tapes has to be more compact than VHS, and therefore more expensive — they are much more suited to portable applications such as camcorders. An EPA tractor was simply an automobile, truck or lorry, with the passenger space was cut off behind the front seats, equipped with two gearboxes in a row. Other formats such as 8mm video cassettes and MiniDV have emerged since, but these formats are by no means in complete competition with VHS. During World War 2 there was a shortage of tractors in Sweden and this lead to the invention of a new type of tractor called the EPA tractor (EPA was a chain of discount stores and it was often used to signify something of lacking in quality). Netscape.

There are also tiny wheeled loaders, officially called Skid-steer loaders but nicknamed "Bobcat" after the original manufacturer, which are particularly suited for small excavation projects in confined areas. Windows and Microsoft vs. Other modifications to the original bulldozer include making the machine smaller to let it operate in small work areas where movement is limited. IBM, Macintosh vs. This is usually a wide open box called a bucket but other common attachments are a pallet fork and a bale grappler. The format war and the "marketing over technology" claims have taken on a life of their own, and have been used as analogies in the battles of the computer industry, including Apple vs. A front-loader or loader is a tractor with an engineering tool which consists of two hydraulic powered arms on either side of the front engine compartment and a tilting implement. Sony ultimately conceded the fight in the late '80s, bringing out a line of VHS VCRs.

One example is that loader tractors were created by removing the blade and substituting a large volume bucket and hydraulic arms which can raise and lower the bucket, thus making it useful for scooping up earth, rock and similar loose material to load it into trucks. Ultimately Betamax did manage to make up some of the difference on recording time, but this was too little, too late. Bulldozers have been further modified over time to evolve into new machines which are capable of working in ways that the original bulldozer can not. The longer tape time is sometimes cited as the defining factor in the format war, as the longer VHS tapes allowed consumers to record entire programs unattended, and arguably created the entire video rental industry by providing sufficient playing time for most feature films to be distributed on a single cassette. Bulldozers are very powerful tractors and have excellent ground-hold, as their main tasks are to push or drag things. Betamax held an early lead in the format war, offering some technical advantages, but by 1980 VHS was gaining due to its longer tape time (3 hours maximum, compared to just 60 minutes for Betamax) and JVC's less strict licensing program. A bulldozer is a tracked-type tractor attached with blade in the front and a rope-winch behind. In fact, however, the root causes of VHS' victory are somewhat more complex.

When attached with engineering tools the tractor is called an engineering vehicle. Since Betamax was widely perceived at the time as the better format, it is often stated that VHS' eventual victory was a victory of marketing over technical excellence. The most common attachments for the front of a tractor are dozer blade or a bucket. As mentioned, VHS was the winner of a protracted and somewhat bitter format war during the early 1980s against Sony's Betamax format. Tractors can be fitted with engineering tools such as dozer blade, bucket, hoe, ripper, and so on. Conversely, an E-300 tape runs for 300 minutes in PAL-SP, but 200 minutes in NTSC-SP. The durability and engine power of tractors made them very suitable for engineering tasks. For example, a T-120 tape runs for 120 minutes in NTSC-SP, but 180 minutes in PAL-SP.

Their versatility and compact size makes them one of the most popular urban construction vehicles. It can easily be derived by multiplying with 3/2 or 2/3, respectively. Their relatively small frame and precise control make backhoe-loaders very useful and common in urban engineering projects such as construction and repairs in areas too small for larger equipment. It is perfectly possible to record and play back a blank T-XXX tape in a PAL machine or a blank E-XXX tape in an NTSC machine, but the resulting playing time will be different than indicated. Often the bucket can be replaced with other devices or tools. In order to avoid confusion, manufacturers indicate the playing time in minutes that can be expected for the market the tape is sold in:. The front assembly may be a removable attachment or permanently mounted. Both NTSC and PAL/SECAM VHS cassettes are physically identical (although the signals recorded on the tape are incompatible.) However, as tape speeds differ between NTSC and PAL/SECAM, the playing time for any given cassette will vary accordingly between the systems.

Buckets with retractable bottoms are also often used for grading and scratching off sand. Likewise, S-VHS machines for the Brazilian market record in NTSC and convert to/from PAL-M. Some buckets have a retractable bottom, enabling them to empty their load more quickly and efficiently. S-VHS machines sold in SECAM markets record internally in PAL, and convert to/from SECAM during record/playback, respectively. Backhoe-loaders are very common and can be used for a wide variety of tasks: construction, small demolitions, light transportation of building materials, powering building equipment, digging holes, breaking asphalt and paving roads. S-VHS only exists in PAL/625/25 and NTSC/525/30. Removable backhoe attachments almost always have a separate seat on the attachment. Dedicated multistandard machines can usually handle all standards listed, some high end model can even convert a tape from one standard to another by using a built-in standards converter.

When the backhoe is permanently attached, the machine usually has a seat that can swivel to the rear to face the hoe controls. regular VHS machines sold in Europe nowadays can typically handle PAL, MESECAM for record and playback, plus NTSC for playback only. When both the loader and the backhoe are permanently attached it is almost never called a tractor, not generally used for towing and usually does not have a power take-off. E.g. As the name implies, it has a loader assembly on the front and a backhoe on the back. These can handle VHS tapes of more than one standards. The most common variation of the classic farm tractor is the loader-backhoe, also called a backhoe-loader. Since the 1990s dual- and multistandard VHS machines have become more and more common.

The spin-offs from the space race have actually facilitated automation in plowing and the use of driverless drone tractors that work in tandem with manned tractors on large corporate-scale farms. The following signal varieties exist in conventional VHS:. These technologies are used in modern, precision farming techniques. Typically, a VHS machine can only handle signals of the country it was sold in. Space technology has found its way into down to agriculture in the form of GPS devices, and robust on-board computers installed as optional features on farm tractors. However, a machine must be designed to record a given standard. Some farm-type tractors are found elsewhere than on farms: with large universities' gardening departments, in public parks or for highway workman use with blowtorch cylinders strapped to its sides and a pneumatic drill air compressor permanently fastened over its power take-off. VHS can record and play back all varieties of analogue television signals in existence at the time VHS was devised.

This enables a single person to attach an implement quicker and put the person in less danger when attaching the implement. This format is most notably used by Fox for some of its cable networks. Another way to attach an implement is via a Quick Hitch, which is attached to the three-point hitch. This format is the least expensive format to support a pre-read edit. The equipment attached to the three-point hitch is usually completely supported by the tractor. There is also a JVC-designed component digital professional production format known as Digital-S or (officially) D9 that uses a VHS form factor tape and essentially the same mechanical tape handling techniques as an S-VHS recorder. Equipment attached to the three-point hitch can be raised or lowered hydraulically with a control lever. This development hampered the sales of the Betamax system somewhat, because the Betamax cassette geometry prevented a similar development.

The three-point hitch was invented by Harry Ferguson and has been a standard since the 1960s. The magnetic tape on VHS-C cassettes is wound on one main spool and uses a gear wheel to advance the tape; the wheel and spool can also be moved by hand. Farm implements can be attached to the rear of the tractor by either a drawbar or by a three-point hitch. Since VHS-C tapes are based on the same magnetic tape as full size tapes, they can be played back in standard VHS players using a mechanical adapter, without the need of any kind of signal conversion. ROPS were first required by legislation in New Zealand in the 1960s. Another variant is VHS-C (C for compact), used in some camcorders. Many farmers were killed by rollovers while operating tractors along steep slopes. W-VHS caters for high definition video.

Row-crop tractors, before ROPS, were particularly dangerous because of their 'tricycle' design with the two front wheels spaced close together and angled inward toward the ground. Devices have also been invented which directly connect a personal computer to VHS tape recorders for use as a data backup device. Before ROPS were required many farmers died when their tractors rolled on top of them. Several improved versions of VHS exist, most notably S-VHS, an improved analog standard, and D-VHS, which records digital video onto a VHS form factor tape. For tractors with operator cabs, the ROPS is part of the frame of the cab. There was a time when higher-end VCRs provided functions for manually removing and adding these index marks — so that, for example, they coincide with the actual start of the program — but this feature has become hard to find in recent models. This is especially important in open-air tractors where the ROPS is a steel beam that extends above the operator's seat. These are normally written at the beginning of each recording session, and can be found using the VCR's index search function: this will fast-wind forward or backward to the nth specified index mark, and resume playback from there.

Modern tractors have rollover protection systems (ROPS) to prevent an operator from being crushed if the tractor rolls over. The control track can additionally hold index marks. Some modern tractors, such as the JCB Fastrac, are now capable of much more tolerable road speeds of around 50 mph. Since good tracking depends on the exact distance between the rotating drum and the fixed control/audio head reading the linear tracks, which usually varies by a couple of micrometers between machines due to manufacturing tolerances, most VCRs offer tracking adjustment, either manual or automatic, to correct such mismatches. To alleviate conditions, some countries (for example the Netherlands) employ a road sign on some roads that means "no farm tractors". Another linear control track, at the tape's lower edge, holds pulses that mark the beginning of every frame of video; these are used to fine-tune the tape speed during playback and to get the rotating heads exactly on their helical tracks rather than having them end up somewhere between two adjacent tracks (a feature called tracking). However, when travelling on public roads, the slow operating speeds can cause problems, such as long queues or tailbacks, which can delay or aggrevate other road users. These advanced features are impossible to find on later-model VCRs due to the rise of digital video formats.

They help give the farmer a larger degree of control in certain situations, such as field work. Another high-end feature was manual audio level control, which made the VHS HiFi format much more useful for high-quality audio-only recording purposes as discussed above. Slower speeds are necessary for most operations that are performed with a tractor. (Due to the different ways in which linear and HiFi audio are recorded, these kinds of dubbing were not possible with the HiFi tracks). This allows the operator more and easier control over working speed than the throttle alone could provide. Without the dubbing features, this task would've required the tape to be copied to another tape which would cause generational loss. Older tractors usually require that the operator depress the clutch in order to shift between gears (a limitation of straight-cut gears in the gearbox), but many modern tractors have eliminated this requirement with the introduction of technologies such as continuously variable transmission. This was useful, for example, for laying a song over a previously edited-together montage of short video clips that were the same total duration as that song.

They have several gear ratios that, generally, provide a range of speeds from less than one mile per hour up to about 25 miles per hour. These would move the tape past the heads and keep the video unchanged while recording new linear audio or keep the linear audio unchanged while recording new video, respectively. Most farm tractors use a manual transmission. Some higher-end VHS and S-VHS VCRs once offered "audio dubbing" and "video dubbing" functions. Almost all modern tractors can also provide external hydraulic and electrical power. Of course, for backward compatibility, hi-fi VCRs still write the linear audio track during recording, and can automatically read it during playback if the hi-fi audio is not present. Modern tractors use a power take-off shaft (PTO) to provide rotary power to machinery that may be stationary or pulled. The excellent sound quality of hi-fi VHS has gained it some popularity as an audio format in certain applications; in particular, ordinary home hi-fi VCRs are sometimes used by home recording enthusiasts as a handy and inexpensive medium for making high-quality stereo mixdowns and master recordings from multitrack audio tape.

Early tractors used belts wrapped around pulleys to power stationary equipment. When the video signal is written by the following video head, it erases and overwrites the audio signal at the surface of the tape, but leaves the deeper portion of the signal undisturbed. Most tractors have a means to transfer power to another machine such as a baler, slasher or mower. These audio tracks take advantage of depth multiplexing: since they use lower frequencies than the video, their magnetization signals penetrate deeper into the tape. Their size—especially with modern tractors—and the slower speeds are reasons motorists are urged to use caution when encountering a tractor on the roads. More recent hi-fi VCRs add higher-quality stereo audio tracks which are read and written by heads located on the same spinning drum that carries the video heads, frequency modulated to the unused frequency range in between the chroma and luma signals. Variations of the classic style include the diminutive lawn tractors and their more capable and ruggedly constructed cousins, garden tractors, that range from about 10 to 25 horsepower and are used for smaller farm tasks and mowing grass and landscaping. In the original VHS format, audio was recorded unmodulated in a single (monaural) linear track at the upper edge of the tape, which was limited in frequency response by the tape speed.

Tractors can be generally classified as two-wheel drive, two-wheel drive with front wheel assist, or four-wheel drive (often with articulated steering). The video bandwidth is achieved with a relatively low tape speed by the use of helical scan recording of a frequency modulated luminance (black and white) signal, to which a frequency-reduced "color under" chroma (hue and saturation) signal is added. Modern farm tractors employ large diesel engines, which range in power output from 18 to 500 horsepower (15 to 400 kW). The vertical resolution of VHS (and all other analog recording methods) is determined by the TV standard — a maximum of 486 lines are visible in NTSC and a maximum of 576 lines in PAL. When travelling on the road in the UK it is mandatory to use the foot pedal to control engine speed. The frequency modulation of the luminance signal makes higher resolutions impossible within the VHS standard, no matter how advanced the recorder's technology. This is a feature of more recent tractors, older tractors often did not have this feature. VHS tapes have approximately 3 MHz of video bandwidth, and a horizontal resolution of about 240 discernible lines per scanline [1].

The foot throttle gives the operator more automobile-like control over the speed of the tractor for road work. An unofficial LP mode with half the standard speed exists on some NTSC machines, but is not part of the VHS standard. It also helps provide continuous power for stationary tractors that are operating an implement by shaft or belt. Because of this, commercial prerecorded tapes were almost always recorded in SP mode. This helps provide a constant speed in field work. Of course, these speed reductions cause corresponding reductions in video quality; also, tapes recorded at the lower speed often exhibit poor playback performance on recorders other than the one they were produced on. Unlike in automobiles, it can also be controlled from a hand-operated lever ("hand throttle"). More recent machines usually allow the selection of longer recording times by lowering the tape speed: LP mode (for PAL and some NTSC machines) halves the tape speed and doubles the recording time, while EP mode (for NTSC and some newer PAL machines, aka SLP mode) drops the tape speed to one-third, for triple the recording time.

The pedal furthest to the right is the foot throttle. Most cassettes have lower recording times because they use thicker tape, which helps avoid jams; careful users generally avoid the thinnest tapes. For tractors with additional front-wheel drive this operation often engages the 4-wheel locking differential to help stop the tractor when travelling at road speeds. A cassette holds a maximum of about 430 m of tape at the lowest acceptable tape thickness, giving a maximum playing time of about 3.5 hours for NTSC and 5 hours for PAL at "standard" (SP) quality. The operator presses both pedals together to stop the tractor. The tape speed is 3.335 cm/s for NTSC, 2.339 cm/s for PAL. The split brake pedal is also used in mud or soft dirt to control a tire that spins due to loss of traction. A VHS cassette contains a ½ inch (12.7 mm) wide magnetic tape wound between two spools, allowing it to be slowly passed over the various playback and recording heads of the video cassette recorder.

This is usually done when it is necessary to make a tight turn. . This independent left and right wheel braking augments the steering of the tractor when only the two rear wheels are driven. Most newer VHS machines do not perform this unthreading step, as due to improved engineering, head-tape contact is no longer an impediment to fast winding. The left brake pedal stops the left rear wheel and the right brake pedal does the same with the right side. Early VHS machines could rewind and fast forward the tape considerably faster than a Betamax VCR since they unthreaded the tape from the playback heads before commencing any high-speed winding. Two of the pedals on the right are the brakes. VHS initially offered a longer playing time than the Betamax system, and it also had the advantage of a far less complex tape transport mechanism.

The operator presses on this pedal to disengage the transmission for either shifting gears or stopping the tractor. VHS became a standard format for consumer recording and viewing in the 1980s and 1990s after competing in a fierce format war with Sony's Betamax and, to a lesser extent, Philips' Video 2000. The pedal on the left is the clutch. Some early reports claim the name originally stood for Victor Helical Scan System. On modern farm tractors there are usually four foot-pedals, for the operator, on the floor of a tractor. VHS officially stands for Video Home System, but it initially stood for Vertical Helical Scan, after the relative head/tape scan technique. This basic design has remained unchanged for a number of years, but enclosed cabs are fitted on almost all modern models, for reasons of operator safety and comfort. The Video Home System, first released in September 1976, better known by its abbreviation VHS, is a recording and playing standard for video cassette recorders (VCRs), developed by JVC (with some of its critical technology under lucrative licensing agreements with Sony) and launched in 1976.

The classic farm tractor is a simple open vehicle with two very large driving wheels on an axle below and slightly behind a single seat (the seat and steering wheel consequently are in the center) and the engine in front of the driver with two steerable wheels below the engine compartment. Viz Video (1993-). These machines were phased out during the 1920s in favour of the increasingly popular internal combustion engine. Buena Vista Home Entertainment (1989-). These were built around steam engines, which were not very safe and could explode or entangle their operators in the belt driven attachments. Miramax Home Entertainment, a unit of Buena Vista Home Entertainment (1989-). The first mechanized farm implements in the 1800's and early 1900's were steam tractors. New Line Home Entertainment, a TimeWarner Company (1989-).

The farm tractor is used for pulling or pushing agricultural machinery or trailers, for ploughing, harrowing and similar tasks. Carolco Home Video, a division of Artisan Entertainment, a Lions Gate Company (1988-1995). The most common use of the term tractor is for the vehicles used on farms. Orion Home Video, a Sony Pictures Entertainment Company (1988-1997). . Anchor Bay Entertainment (1980s-). In Britain the word "tractor" usually means "farm tractor", and using "tractor" to mean other types of vehicles is known of in the vehicle trade but unfamiliar to much of the general public. Hi-Tops Video, a Heron Communications Company (1985-1992).

Most commonly the word is used to describe a vehicle intended for such a task on some other vehicle or object. Simitar Entertainment (1980s-1990s). A tractor (from Latin trahere "to pull") is a device intended for drawing, towing or pulling something which cannot propel itself and, often, powering it too. Touchstone Home Entertainment, a unit of the Walt Disney Company (1984-). White. Artisan Entertainment, a Lions Gate Company (1984-). Steiger Tractor Company. Family Home Entertainment, a division of Artisan Entertainment, a Lions Gate Company (1982-).

Oliver Corporation. NBC Home Video, an NBC/Universal Company (1981-). Minneapolis Moline Tractors. Universal Studios Home Video, an NBC/Universal Company (1980-). Massey Ferguson. Magnetic Video, the first duplicator/distributor of movies on video cassette for home use (1977-1981). Ford Tractor Co. Vestron Video, a division of Artisan Entertainment, a Lions Gate Company (1979-).

Farmall. MGM Home Entertainment, a Sony Pictures Entertainment Company (1979-). Deere & Company. Media Home Entertainment, a Heron Communications Company (1978-1992). David Brown Limited. Warner Home Video, a TimeWarner Company (1978-). Case IH and New Holland (now brands of CNH Global). HBO Video, a TimeWarner Company (1978-).

Case Corporation and International Harvester. Sony Pictures Home Entertainment (1978-). Big Bud. Walt Disney Home Entertainment (1978-). Allis-Chalmers. Twentieth (20th) Century-Fox Home Entertainment, a News Corporation Company (1977-). Paramount Home Video, a Viacom Company (1976-).

E-XXX indicates playing time for PAL or SECAM in SP speed. T-XXX indicates playing time for NTSC or PAL-M in SP speed. PAL-M, Brazil). PAL/525/30 (i.e.

NTSC/525/30 (Most parts of North and South America, Japan, South Korea). MESECAM/625/25 (most other SECAM countries, notably Eastern Europe and Middle East). SECAM/625/25 (SECAM, French variety). PAL/625/25 (most of Western Europe, many parts of Asia and Africa).