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Let's look at the graphic for video and audio once again. One important function that you don't see listed is motor control. The reason for this omission is that even though it is very important to the operation of any video recorder it doesn't require signal conversion to function. The motors used for the video drum and capstan are certainly important the incoming and outgoing video picture but they are controlled separately. Because of this we can deal with them independently and then show how they are integrated into the overall performance of the VCR. This is what we are going to do now. First let's look at what happens when a recording takes place because it will help in understanding of why precise motor function is so important. Please click on the picture. Here we see two illustrations of the actual tracks that are recorded on a Beta video tape. In the background is a highly magnified representation of how the tiny magnetic particles would look after being energized by the various recording heads (shown in Beta III speed). The illustration in the center shows the same thing but in a line drawing. At the top edge of both is the audio track. Along the bottom edge is the control track and in the center is the scanner tracks (the ones at an angle). For all three speeds used in the Beta format it is imperative that the tape travel through the tape path in a regulated smooth manner. For good audio recording and reproduction the capstan motor has to pull the tape past the head at the same speed during both recording and playback. (Keep in mind that for this discussion we are only concerned about the linear or what Sony calls the normal audio track, Betahi-fi is something completely different and will be explained later.) If this were a audio recorder only the operator would set the speed for both recording and playback. But with video recorders, as you know, only the recording speed can be chosen, playback speed is automatic (selected by the machine). So how does the capstan manage to run so well regulated? Early Betamaxes could rely on the 60 cycles coming from the AC house current provided by the power company. Slight deviations were smoothed out by the use of a mass flywheel driven by a belt coming off of a capstan motor. But this system was flawed. Rubber belts slip, get old, stretch and are subject to temperature so the system was quickly changed to one where the rotation was controlled by the vibrations of a crystal clock. Remaining text is not ready to publish at this time. ipsum dolor sit amet, consectetuer adipiscing elit. Aliquam aliquam massa eget nulla. Mauris sit amet nisl. Maecenas auctor. Nulla ultrices purus id ante. Nunc ut enim. Duis sed elit sed lectus accumsan tempus. Curabitur eget dui. In felis diam, sodales nec, sollicitudin sed, lacinia in, odio. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Praesent tincidunt elementum nulla. Morbi gravida lectus malesuada pede. Aliquam eget justo a lacus pellentesque ultricies. Mauris ipsum. Nam nec magna sit amet magna dignissim dignissim. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Nunc nec pede quis diam iaculis euismod. Mauris sit amet risus id justo bibendum varius. Maecenas vehicula elementum orci. Etiam adipiscing dictum tellus. Nullam neque elit, dictum ut, venenatis a, dapibus at, erat. Phasellus vehicula, lorem vitae dignissim pellentesque, enim mi auctor mi, scelerisque ultricies leo lorem in ante. Maecenas et mi at ante consequat laoreet. Sed consectetuer tortor id arcu. Donec in erat. Nam accumsan volutpat dolor. Nulla in orci. Donec nunc. Praesent convallis blandit lectus. Nullam porta euismod risus. Etiam nisl quam, egestas at, tincidunt a, lobortis sit amet, tellus. Aenean tristique tortor vulputate sem bibendum blandit.
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