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Shown above is tape traveling over the ACE and related guides when everything is adjusted correctly and traveling properly. There are no curls or wrinkles. If the tape were reversed, it would remain located in exactly the same relative position on the ACE and not crawl either up or drown.
Assuming these conditions are not being met click on the picture and examine these two tape travel illustrations. As you can see the tape is running high in the top of the photo and way too low in the bottom. Both would result in a loss of the pIcture, loss of audio or maybe damage to the tape. Now to see it the scope. Click on the picture. The waveform in the upper right shows distortion of the path. The graph in the middle is from the service manual and the bottom left illustration shows how the adjustment affects physical movement of the ACE assembly. When the waveform resembles the one pictured first step is to try to tilt the ACE and pull the waveform back to a flat even form. If this cannot be done (click on the photo) then the next step would be to loosen the number seven and eight guides slightly, adjust the tilt and produce a signal as the one in the upper right. After this is accomplished lower the guides and produce the waveforms in the next photo. Click again. Starting at upper right the waveform should start here as the guides are lowered and end up producing the middle left and bottom left illustrations as the tracking is turned from maximum to a reduced 60%. Once again with no curl or wrinkles present. If reverse scanning makes the tape crawl up or down across the ACE then the number ten guide lock screw must be loosened and the guide raised or lowered to center the tape. If the tape will not travel both directions without crawling around on the ACE, and the number ten guide cannot correct it, then the tilt is off and the adjustment process must be repeated. This must be done as many times as necessary until the proper waveform can be obtained and the tape travels in both directions without wandering. Done correctly the tape ends up traveling through the tape path with little or no resistance, this is why the Beta system treats the tape so well and allows for such neat special effects. So as you can see the tape path alignment can wear on your nerves. There are several things to do before the alignment can be set aside as successfully completed. Now we adjust ACE HEIGHT, AZIMUTH AND CENTER. But before leaving this panel look close at the bottom of the tape where it crosses over the lower electromagnet (silver rectangle). This pick up in the ACE is slightly larger than the area it records on the tape. Same goes for the top one too. This makes them a poor judge for how high or low the ACE height needs to be. The correct height is obtained by checking the amplitude of the monaural audio coming from the test tape. This is next, now click here. To go back to the previous page click here   Note: notice those white circular washers beneath the guide adjusting nuts. They are made of ceramic material and are super hard. This is done so they can take years of constant contact with the knife sharp edge of a tape without wearing out.
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