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Before Mitsushita had the good fortune of acquiring the M-loading system, later to become VHS, they introduced an interesting trial format. It was called the Quasar model VR1000 or the "The Great Time Machine" (That slogan was used over again when they later released their VHS machine using their JVC and Panasonic versions). Released to the public before the Betamax it was roughly the same size and weight. The cassette was as large as a hard bound book, was heavy and the tape spools inside were stacked on top of each other. When it was inserted into the carrier (cassette holder) and then lowered into the machine the video drum, guides and spool drives entered into the cassette. Yep, the video drum sat inside the cassette during operation. More on this unique approach later but first a look at the overall exterior design of the machine. Click on the picture and the optional clock/timer is shown. Click again and the controls behind the front panel door and the sliding handle can be seen. The handle was used to move mechanisms inside which prepared the cassette and machine for operation. Also when it was positioned at the extreme left position it would ejected the cassette as it was pressed down. Inside the flip down door is located a switch to select black and white or color recording. This option was offered on several early units because B/W is somewhat sharper than color. Also selecting B/W prevented color from bleeding into the picture. Next is an interesting adjustment called skew. Back in the days of tube-type televisions, flagging or bending at the top of the picture could occur during playback of video tapes (we're talking reel-to-reel here). A correction for this was to slightly alter the occurrence of the starting frame event so the TV could match the playback timing. The adjustment was called 'skew" since it skewed the top of the picture slightly left or right. This problem was to correct itself when later design TVs began using the faster transistors and ICs instead of tubes. A tracking control knob is here along with a heater switch so you could turn on a internal blower and remove any dew or moisture that might be present inside the machine. (Video machines won't play if the drum gets damp.) If you click on the picture you get a view of the keyboard function buttons. Play and monitor were pressed together to record. Each could be pressed separately with monitor alone producing no tape movement. Doing so only passed through what was coming from the tuners (or the external source plugs). Notice the on/off button. No other machine used a piano type toggle lever for this function. The next picture shows the cassette. Notice the notches on either side. If they were not there inserting the cassette would require very big hands. The next picture is looking down into the tape transport with the top of the cassette carrier removed. Click on the picture and the entry door in the cassette can be seen for the pinch roller. Since the capstan was located inside the cassette during operation (you'll see this later) a large opening was needed to allow the pinch roller to enter. A siding door prevented dirt and dust from finding it's way inside the cassette and on the tape. The steps 1-2-3 show how it was open by the carrier (or holder) when the cassette was pushed in. The next photo gives you a view of the inside with the top cover of the unit removed. Notice the pinch roller, capstan, audio/control heads and dehumidifier (heater). The next picture points out the cables used to move the unloading pins and video drum collar. The collar has splines on it to catch several pins inside a rotating tube that holds the tape in a circular position inside the cassette. You'll see this better in the coming pictures. Click again and the video drum, guides and unlocking pins are shown. The next picture shows the slide handle and with the attached cables. Now that you have a general idea about some of major moving parts and the action that is going to take place when the cassette is inserted, let's a closer look at it. Click the picture and you'll see the tube in the up position with the tape wrapped around it (The top of the cassette is removed). The tape is not touching the guides at this time. Notice the audio and control heads (silver blocks of metal) just left of center. We're going to see them up close a little later on. Also note the supply reel with half inch tape and take up reel beneath it. They are stacked on top of each other. This will be easier to see later. Click the picture again and now the tube has been rotated down (by moving the slide handle). The tape is now wrapped around the video drum and is now also on the guides. The machine is not running, but everything is ready to go. Click the picture and you will see how the unit knows when the tape comes to the end or is at the beginning. A duel photocell arrangement and special leader tape was used to keep the electronics informed. Pretty snazzy? The two tape reels can be seen a little better in this photo also. Click the picture again and the only video head is shown (on the disk upside down). Only, as in only one head was used. The tape makes a full 360 degrees of travel around the drum (full wrap) so only one was used. All other designs that came later recorded using 180 degree wraps and switched to interlace two traces on the screen for a single picture. The VR1000 still switched the scans but all the information was recorded in one complete rotation. Also, there were guard bands on the tape (blank unrecorded spaces between scans) and only one recording and playback speed was available. Click the picture and now you see the operation as the tape is being played. The pinch roller is pressed against the capstan. The tape is moving over the guides. The unlocking pins have the various cassette holding devices out of the way and the audio/control guide has the tape pushed against their recording surfaces. What's missing? There is no tension bar or arm to keep the tape smooth against the video drum. How was this done? Click on the picture and now you will see the underside of the machine. Here's an innovative idea that never made it to other designs. A special 7 volt motor, called a tensioner motor, turned a pulley that kept just the right amount of tension on the take up reel to correctly pull the tape over the video drum. It did this by counting the rotation speed of the reel. Notice the alternate bands of black and white on the disk just below the motor, this rotated with the take up reel. The counter pickup (a photocell) watched these bands go by and sent a signal to special circuitry that adjusted the speed of the tensioner motor. Things could go wrong if belts slipped or something became dirty, but when it worked, it was very effective. Back tension for the audio/control heads was not as critical, so a simple felt pad was used to keep a slight drag on the supply reel. The last picture (next) shows the drive motor that spun the heads, turned the capstan flywheel and provided rewind and fast forward. It was big, but they all were back in this era. The VR1000 suffered from being complicated and unreliable, and of course it didn't succeed. Good thing too, because had Mitsushita held onto this design they would have missed their window of opportunity to develop VHS. To go back to the index page for the other early designs click here. To go to the information on the Cartivision VCR click here. To go to the information on the V-cord machine click here. |