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When video tape is damaged or is being injured it usually shows up in the playback picture. This is an indication that all is not well either with the machine or the tape. Tape problems will only occur in the same spot or only with the individual cassette. While this is troublesome and can make the video unwatchable it isn't as bad as when the VCR is causing the issue. Then it will repeat with every tape you play. So it is wise to keep this in mind when watching your videos. A problematic Beta needs immediate attention to insure that your media is not compromised. This section identifies thirteen of the most common types of traumas that can happen to videotape. Most of these are caused by the machine but a few can be the result of improper handling or operation. Each illustration shows what the issue visually and physically looks like on the tape and also how it looks when watching it on a TV monitor. Keep in mind that video reproduction can vary depending on the machines circuit design, the monitor used and the type of tape. This is only a general guide. In almost all cases tape damage is not reversible. Before you begin observe the video to locate the general area of the trouble. Then eject the cassette and prepare it for inspection. Note: Most Sony Beta VCRs when they eject a cassette wind the tape back a short distance back onto the supply reel. Sanyo and Toshiba run the tape slightly forward. Remember this when looking out for the offending area. To visually examine the tape surface you will need to flip up the cassette lid to expose the tape loading pocket. This pocket is indicated in the picture above. To release the lid use a pointed object such as the tip of a file, tooth pick or fingernail. Insert this into lid lock pocket and trip the lever. Flip the lid open and up then use adhesive tape to hold it open. Try not to touch the video tape inside. Check and make that the tape is over the video tape stand off in the center (see above). If it is on the other side it is located incorrectly and will certainly cause a problem when the cassette is loaded into the machine. If the problem you encountered was related to cassette loading then this relocation may be all that was needed. This kind of location problem is not machine related but it can certainly cause damage to the tape and even the machine. Examine the photo above and familiarize yourself with the illustrated parts. To inspect the tape begin by visually locating the bad spot on the tapes surface. To do this carefully rotate the take-up spool in the direction shown. The other reel will also turn as you do this. For this you can use your fingers, a dime or get creative and fashion some kind of a tool that will fit inside the spool cavity. I offer a tool called a cassette crank that makes turning the spools a snap. It is in the "Beta Accessories" section, to go there click here. The smoother you can do this the easier it will be. In most cases you will only need to rotate the take-up reel (or supply reel) a few turns to get to the damaged area. Now lets get started. Click on the picture above. This will be your guide that shows how the two indications will be displayed. Each picture after this one will use this pattern and will explain what each problem looks like. I will indicate in the discussion when you should click on the picture to change it to the next cassette issue, and they are also going to be numbered. Click the picture again.  The first picture in the series is numbered 1 and it illustrates an undamaged tape and the resulting normal playback picture. Notice that the tape surface is smooth, flat and uniform with no scratches, buckles, curls or wrinkles. The resulting playback of a standard test pattern (in the lower right) is sharp and steady. Click the picture to see the first example of the most common kind of damage, the horizontal scratch.  You are now at picture number 2. The tape injury can be seen as a horizontal scoring, fine line or tiny crease running along the length of the tape. On the monitor it shows up as a white line that runs in a stationary position through the picture. Its location on the tape usually corresponds with the location in the video image, but if it is near the very top or at the very bottom edge it may not be visible. Instead it will disturb the audio or disrupt the stability of the picture. The scratch is usually caused by a sharp foreign object stuck to something in the path area. It may be a lump of oxide, a foreign object or dirt. This can be corrected by having the VCR reconditioned. If the VCR features Betahi-fi buzzing or audio distortion might occur. The machine might even revert back to the monaural audio track. Click on the picture and take a look at example 3. Number 3 is a ripple along the bottom edge and it is usually happens when the tape travels down too low against the bottom of a tape guide. Running too low can be caused by a hard pinch roller, dirty capstan, damaged guide, oxide build up or a tape path component (alignment) problem. The control track that tells the machine to start each picture is recorded in this bottom area. This distortion on the bottom edge can be very annoying because it makes it hard to maintain a steady picture. You might have to constantly adjust the tracking but in most cases the video becomes unwatchable. If the wrinkle is bad enough you will lose the playback picture altogether but it can still be seen in pause and scan because these functions don't require the control track pulse. The VCR generates a false tracking signal in these modes.
The tape is ruined but if the machine is causing the problem it can be corrected by having it reconditioned or repaired.  The next example, number 4, is almost the same as 3 but this time the tape has traveled up too far. Culprits are the same as the bottom ripple. This area is where the monaural or standard audio is recorded. If it is bad enough the sound will be low, fluctuate or disappear altogether. The tape is usually ruined but if the machine is causing the problem it can be corrected by having it reconditioned or repaired. Click the picture again. Example 5 is tape curl under. It is similar to the bottom ripple already seen but the cause is usually from the tape winding on the reels inside the cassette too low, or in the case in the next picture, number 6, too high. If encountered more than a few times it is an indication that reconditioning or repaired is needed. The tape may or may not play correctly. Click the picture. Example 6 is tape top curl.This can be caused by a faulty tape guide, a cassette not seated properly or a tape tension problem. This can be corrected by having the VCR reconditioned or repaired. The tape may or may not play correctly. Normal audio (monaural) can be weak or low. Click the picture again. The next example, number 7, is vertical wrinkles or creases in the tape. This is the can be caused by a tape tension error, capstan malfunction, or a rewind or fast forward problem. In this example the tape became wadded up inside the machine and wrapped around the capstan. It can also be caused by the use of a harsh pop-n-stop type of tape rewinder (more on this later). The tape is ruined in the spot but if the machine is causing the problem it can be corrected by having it reconditioned or repaired. Click the picture.  Picture 8 shows a center crease or folding. A capstan with oxide buildup can cause this and so can a hard pinch roller, a bent or missing guide or improper tape tension. The tape is ruined. This can be corrected by having the VCR reconditioned or repaired. Click the picture.  Picture 9 is the diagonal crease. This can happen when the tape wanders out of the path guides and runs against the top or bottom of the ACE assembly, or up against the top of the capstan tower. Sometimes the tape may even fold completely over and begin running on the back side. When this happens total loss of the video will result. The tape is ruined. This can be corrected by having the VCR reconditioned or repaired. Click the picture.  Picture 10 is an extreme example of what has already been illustrated with the top curl or ripple. Except in this case it is more severe because the tape didn't load properly, missed a guide and was forced to make a wrong turn inside the machine. Sometimes this will cause a complete unit shut down and almost always requires major surgery to get the tape out. This damage can also appear along the bottom of the tape. The tape is ruined and if this damage is caused by the VCR it can be corrected by having it reconditioned or repaired. Click the picture.  Picture 11 shows a tape splice, something that should never happen with video tape. The big reason for not doing this is the space where the two ends meet is huge compared to the tiny gap of the video heads. When they pass over it the impact can cause them to crack, making them useless. Also the adhesive from the splicing media can squeeze out and get smeared all over the tape path surfaces resulting all kinds of operational problems. Video tapes should never be spliced, period. This is not a machine error, but it will cause problems. The tape is ruined. Click the picture.  In picture 12 the tape has become stretched from an abrupt stop. This can happen if a sensor fails to detect the end of the tape during the winding. The full force of the reel motor is then transferred to the tape, making it stretch or even break. An abrupt stop can even cause the tape path components to become damaged. This type of trauma can also happen from using a poorly designed tape rewinder (more on that still later). The tape is ruined. This can be corrected by having the VCR reconditioned or repaired. Click the picture.  Number 13 a problem that is becoming more common as cassettes age. Here a glued on friction tab has come loose from the inside of an older cassette and become attached to the tape. Most of the time it travels into the machine and the result is almost always messy. The soft adhesive spreads around on the path components and the tape drags through it. The machine is not at fault in this case but it requires a major clean up effort. Worst case is if the spinning video heads slam against the tab, in which case they will be ruined. This tab design was changed in later cassette to eliminate this problem. This can be avoided by inspecting your cassette to make sure they don't have loose tabs. I have an article that covers the tab issue. It is available from the HOW TO USE panel that opened when you entered this section in the browser (the green dialog box). Failure can be corrected by having the VCR reconditioned or repaired. Click to the next picture. Picture 14 shows what can happen when a pop-n-stop type rewinder is used. The force and inertia required to stop the motor and pop the top open on these types of rewinders can cause the tape to bunch up, stretch, fold over or even break. These winders are so hard on tapes that movie rental providers abandoned their use altogether. Some even resorted to requiring renters to rewind the tapes before returning them. Remember back when their tapes had the label: Be Kind - Rewind? Never use a pop-n-stop rewinder if you care about your tapes (and your machine). Click the picture.  The next and final picture shows a video tape with no damage but the playback picture is flagging at the top. Called skew, this annoying event can occur for several reasons. One is if the tapes have become stretched from being stored in a fluctuating environment. Another is playing tapes back on a machine with a forward back tension setting that is different (in error) from the one on which it was recorded. Even though there is a factory standard for setting back tension many circumstances can upset this adjustment. Age of the tape, stretching and even the design of the VCRs video circuitry can all contribute to flagging. Also, the original machine may have been out of adjustment when the recordings were made. Another culprit can be the TV monitor itself. If the timing circuit isn't quick enough to start the picture scanning at the right moment, the resulting time lag can cause the start (top) of the picture to get delayed, causing it to bend over. This flagging issue has been around as long as video tape recording. Some of the first recorders even had a skew adjustment to compensate for differences from machine to machine. But as VCRs became more sophisticated and tension settings were standardized the skew adjustment was removed. Also televisions with transistorized timing circuits had faster scanning recovery times which is supposed to eliminate this event. Short of adjusting the machine to match the tapes (which can adversely affect new recordings) about the only solution to this problem is to try a different TV channel for playback, using a different television, or inserting a video timing correction device in the video out circuit. As a last resort using a different VCR might help. Why doesn't this problem affect television programs viewed off the air? Because that picture is being timed to the steady 60 cycles provided by your power company to both your home and the broadcast station. Something entirely different from your TV trying to match the timing coming from your VCR. More information on this subject is available by searching the Web. There is one last picture I want you to see. Click again and look at these sorry cassettes. Only put one of these into your precious VCR if you MUST see the content. This stuff is nasty, sticky mold. It is a biological organism and running it through the machine will smear plant residue everywhere. It will stick to the video heads and make viewing more difficult. It is slippery so tracking becomes a challenge. Repair or, at the very least, a thorough cleaning will be required after the incident. After all this warning If you still MUST run these cassettes do this, let them thoroughly dry out first. Then the mold comes off the tape as a dry powder. It is still messy and it will require a cleaning afterwards. But there is a little less chance of destroying your video heads this way. To dry them out place them in a plastic bag along with a bunch of desiccant. You are trying to kill the plant by depriving it of water. Information on drying can be found on the web. There is one last picture and it shows the mess it makes inside a Beta VCR. The white skeletal remains of the dry mold can be seen piled up in just these areas, but It would be like this throughout the tape path. Special information about older cassettes: Propelling a foreign object like a friction tab into your Beta is about the worst thing that can happen to it. Fortunately this is rare but it will become more common as time goes by. How can you tell? To see if a cassette is a suspect hold it top up with the lid away from you and look inside through the plastic window. All the way to the front you should be able to see the tab and how it is attached to the inside. (It helps if some of the tape is wound off the reel so you can also see through the top of the spool.) If you see bubbly glue or that the tab is coming loose then this cassette is going to cause enormous problems in the future. Is there a fix for this? If you are industrious you can remove the four bottom screws to open the cassette shell and press the tabs back down, there are two of them. It isn't a real repair but it will extend the time before they eventually come off. A more permanent fix is to remove the reels and super glue the tabs in place after pressing the down. If you want to attempt this it is best to remove the reels with the foil leader all the way to the end. This way there is less chance of the delicate tape being damage during reassembly. Once you're done you can rest assured that the tabs will not come out. If you want to speed the super glue up you can use an accelerant. It will cause crazing and the glue gets hot, but you don't have to wait forever for it to set up either (and I'm not saying super glue is the only glue you can use either). To open a panel about friction tabs repair click here. (This panel will be replaced by the new one.) To open a panel on how to properly store your cassettes click here. (This panel will be replaced.) |