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It would be nice for your VCR if rental movies had never been invented. You have no idea of the history of any tape you bring home. The following may also apply to tapes in your video library or tapes given to you by friends or relatives: * The tape may be old and old tapes shed a lot more oxide and crud than newer tapes. A single playing may clog your video heads. * The tape may have been damaged by a prior viewing and one pass through may ruin your expensive video heads. A tape that has been seriously crinkled due to a VCR tape eating incident and then wound back into the cassette may be a ticking time bomb for your VCR. A tape with a partial break or one that has been improperly spliced is even more likely to cause serious damage. Do not splice tapes - see the section: "Recovering damaged or broken tapes". * The cassette mechanism itself may have been damaged (from being dropped or stored in a hot automobile) with unknown consequences for your VCR. Note: if you should ever damage a rental tape as a result of a cranky VCR or for any other reason, don't just give it back to the video store. Please let them know. Also, if your VCR should jam with a tape inside, do not forcibly extract it - read the appropriate sections later in this document. If in doubt, let the video store know what happened and follow their recommendations. Given that you are not likely to give up the movie couch potato addiction, some problems can be avoided by fast forwarding a couple of minutes into the tape before hitting PLAY. Damage to rental tapes often occurs near the start - and this will avoid some of the useless coming attractions as well! If you notice the video breaking up or deteriorating while you are watching, immediately ejecting the tape may be the most prudent option since the worst may be yet to come! While I cannot control your viewing habits, playing a lot of old, dirty, deteriorated tapes (rental or from your own tape library) will eventually take a toll on your VCR. At the very least, you should perform a general cleaning and inspection at more frequent intervals. (From: Jim Lagerkvist (jlager@tir.com)). Renting a video tape has all the same potential consequences as renting a hooker. That tape may pass to your machine anything from pizza grease to splices made from duct tape or staples. I keep two VCRs in my house. One for rental tapes and another for known trusted tapes.
Once you remove the cover(s) of a VCR (ignoring the warnings about no user serviceable parts, etc.), there are some risks to you and your VCR. You also, of course, void the warranty (at least in principle). Therefore, if the unit is still under warranty, having it serviced professionally may be your wisest option. Stay away from the line side of the power supply - put electrical tape over the exposed connections. To be doubly sure, tape a piece of cardboard or thick plastic over the power supply section. Other than that, there is more danger of damaging the VCR by accidentally shorting something out or breaking a little plastic doodad than of you getting hurt. * Don't wear any jewelry or other articles that could accidentally contact circuitry and conduct current, or get caught in moving parts (protect long hair as well). * If circuit boards need to be removed from their mountings, put insulating material between the boards and anything they may short to. Hold them in place with string or electrical tape. Prop them up with insulation sticks - plastic or wood. * Connect/disconnect any test leads with the equipment unpowered and unplugged. Use clip leads or solder temporary wires to reach cramped locations or difficult to access locations. * If you must probe live, put electrical tape over all but the last 1/16" of the test probes to avoid the possibility of an accidental short which could cause damage to various components. Clip the reference end of the meter or scope to the appropriate ground return. * Perform as many tests as possible with power off and the equipment unplugged. For example, the semiconductors in the switching power supply of a VCR can be tested for shorts and the fusable resistors can be tested for opens. * If you need to probe, solder, or otherwise touch circuits in a switching power supply with the power off, discharge (across) large power supply filter capacitors with a 2 W or greater 20-100K resistor and then verify with your voltmeter. * The use of GFCI (Ground Fault Circuit Interrupter) protected outlet is a good idea but will not protect you from shock from many points in a line connected power supply. A circuit breaker is too slow and insensitive to provide any protection for you or in many cases, your equipment. A GFCI may prevent your scope probe ground from melting should you accidentally connect it to a live circuit, however. * Don't attempt repair work when you are tired. Not only will you be more careless, but your primary diagnostic tool - deductive reasoning - will not be operating at full capacity. * Finally, never assume anything without checking it out for yourself! Don't take shortcuts!
Many problems have simple solutions. Don't immediately assume that your problem is some combination of esoteric complex convoluted failures. For a VCR, it may just be a bad belt or an experiment in rock placement by your 3-year old. Try to remember that the problems with the most catastrophic impact on operation (a VCR that eats tapes) usually have the simplest solutions (replace the idler tire). The kind of problems we would like to avoid at all costs are the ones that are intermittent or difficult to reproduce: the occasional interference or a VCR that sometimes will not record your favorite soaps on alternate Thursdays before a full moon. If you get stuck, sleep on it. Sometimes, just letting the problem bounce around in your head will lead to a different more successful approach or solution. Don't work when you are really tired - it is both dangerous and mostly non-productive (or possibly destructive). Whenever working on precision equipment, make copious notes and diagrams. You will be eternally grateful when the time comes to reassemble the unit. Most connectors are keyed against incorrect insertion or interchange of cables, but not always. Apparently identical screws may be of differing lengths or have slightly different thread types. Little parts may fit in more than one place or orientation. Etc. Etc. Pill bottles, film canisters, and plastic ice cube trays come in handy for sorting and storing screws and other small parts after disassembly. Select a work area which is well lighted and where dropped parts can be located - not on a deep pile shag rug. Something like a large plastic tray with a slight lip may come in handy as it prevents small parts from rolling off of the work table. The best location will also be relatively dust free and allow you to suspend your troubleshooting to eat or sleep or think without having to pile everything into a cardboard box for storage. Another consideration is ESD - Electro-Static Discharge. The electronic components in a VCR are vulnerable to ESD. There is no need to go overboard but taking reasonable precautions such as getting into the habit of touching the chassis first before any of the electronic components is a good practice. The use of an antistatic wrist strap would be further insurance. A basic set of precision hand tools will be all you need to disassemble a VCR and perform most adjustments. These do not need to be really expensive but poor quality tools are worse than useless and can cause damage. Needed tools include a selection of Philips and straight blade screwdrivers, needlenose pliers, wire cutters, tweezers, and dental picks. A jeweler's screwdriver set is a must particularly if you are working on a portable VCR or camcorder. For adjustments, a miniature (1/16" blade) screwdriver with a non-metallic tip is desirable both to prevent the presence of metal from altering the electrical properties of the circuit and to minimize the possibility of shorting something from accidental contact with the circuitry. You should not need any VCR specific tools with the possible exception of a miniature metric hex key wrench set for loosening the set screws on the roller guides should you need to perform a tape path alignment. I have never needed a VCR head puller. You can make a tool for the special nut found on many A/C head assemblies for tracking adjustment by filing a slot in the blade of a straight blade screwdriver. A low power fine tip soldering iron and fine rosin core solder will be needed if you should need to disconnect any soldered wires (on purpose or by accident) or replace soldered components. See the document: "Troubleshooting and Repair of Consumer Electronics Equipment" for additional info on soldering and rework techniques. For thermal or warmup problems, a can of 'cold spray' or 'circuit chiller' (they are the same) and a heat gun or blow dryer come in handy to identify components whose characteristics may be drifting with temperature. Using the extension tube of the spray can or making a cardboard nozzle for the heat gun can provide very precise control of which components you are affecting. For info on useful chemicals, adhesives, and lubricants, see "Repair Briefs, an Introduction" as well as other documents available at this site. If you have several VCRs or do repairs for friends (former friends?), there are inexpensive kits of VCR mechanical parts like washers and springs that come in handy. General belt or similar kits are not worthwhile unless you are in the service business - there is too much variety in the sizes and other characteristics of these types of parts to make an assortment a good investment. Note: while working with the top off, you may need to put pieces of strategically located cardboard over the area of the cassette to block extraneous light from causing erratic behavior (modes aborting, not starting at all, etc.) with the start/end-of-tape sensors. Not all VCRs are sensitive to extraneous illumination but I have been bitten more than once by not doing this. Using overhead instead of direct illumination will probably help as well. In extreme cases, placing electrical tape over the end sensors may be needed but this will likely confuse the microcontroller under certain conditions into thinking that a non- existent tape is present - or if your troubleshooting will permit, leave a cassette in the transport. (I have heard of at least one case where this was a problem even for normal operation - apparently, light was falling on the VCR in just the wrong way where it happened to be located. The VCR would enter rewind mode regardless of what the helpless human wanted unless tipped on end!)
Don't start with the electronic test equipment, start with some analytical thinking. Many problems associated with consumer electronic equipment do not require a schematic (though one may be useful). The majority of problems with VCRs are mechanical and can be dealt with using nothing more than a good set of precision hand tools; some alcohol, degreaser, contact cleaner, light oil and grease; and your powers of observation (and a little experience). Your built in senses and that stuff between your ears represents the most important test equipment you have. A DMM or VOM is necessary for checking of power supply voltages and testing of sensors, LEDs, switches, and other small components. Unless you get deep into the electronic repair of VCRs, an oscilloscope is not required. There are two items of important test equipment that you probably already have: * A video signal source - both RF and baseband (RCA jacks). Unless you are troubleshooting tuner or video/audio input problems, either one will suffice. RF sources include a pair of rabbit ears or an outdoor antenna, a cable connection, or a VCR with a working RF modulator. Similarly, a working VCR makes a handy baseband or RF signal source. * A display device. A video monitor or TV makes an excellent video signal display. Many video problems can be diagnosed by just examining the picture. If you have an old TV with a vertical hold control, this is useful when adjusting backtension, should the need arise. A B/W TV is adequate for many of the tests you will be performing.
If you have no prior experience with precision electromechanical repair, don't just jump in as the following actual experience demonstrates: (From: someone who would prefer not to be identified). "Ok, I did something dumb. I was given an old VCR (early 80s) a couple weeks ago (JVC-7100U). It stopped playing and recording, but FF and rewind worked fine. Reading the FAQ, I decided to check it out. I took the top off, and was trying to make the motor run so I could see the problem. There was an incandescent light, and I figured there was a light sensor, so I moved the lamp out of the way. The FAQ suggests electrical tape over the lamp, but I hadn't read it yet. My manipulation caused the lamp to fail. Until I could replace it, I just jumped the connection, which worked fine for awhile. I had just figured out the problem with play/record was a drive wheel not making contact with the take-up reel. It seemed to be a result of a weak spring, and I was trying to figure out which one, when the screwdriver I was manipulating the arm with slipped, and contacted the back side of a circuit board. Lesson number two: Use a chopstick for that purpose. I believe it was at this point I realized I got no reaction from any of the VCR control buttons, so maybe I shorted something out. All the buttons worked before. Even worse, as I was reinstalling the tape loading mechanism, the screwdriver slipped again, in a different place, and I did see a flash when it contacted the back of the circuit board. Whoops." Don't let this happen to you. Or, at least start out with an old expendable VCR and accept the hits to your pride!
When troubleshooting mechanical problems in a VCR, one of the handiest accessories is a cassette cheater - a frame to fool the VCR into thinking there is a cassette in place so that you have access to the reel spindles and idler. You can buy these for $6-12 but you can make one that is almost as nice: * Take a discarded cassette, open it up and throw away everything but the top and bottom halves and the screws. * Punch out the plastic windows - and somewhat more of the top and bottom if you are so inclined - relatively little of the original structure is actually needed to fool the microbrain of the VCR! The more open the cheater is, the easier it will be to see and access guts of the VCR while running. * Reassemble the two halves of the cassette with the screws (you did save the screws, right?). * Put a bit of black tape over the sensor holes on the sides of the cassette (near where the hinge pins of the flap went). These cheaters will load and 'play' just fine except that some machines actually sense that the supply reel is being turned by the tape movement during loading or always and will shut down if it isn't (among other peculiarities) so you may have to do this by hand. There are several benefits to using one of these, one of which is that there is no chance of ruining a prized tape due to a hungry VCR. You will also be able to feel the spindles to get an idea whether they are turning properly and with enough torque in all modes. If you break out enough of the top and bottom, you will have access to the idler and other under-cassette parts at the same time. If you examine one of the commercial cassette cheaters, you will see that very little is needed beyond the outer frame as long as it sits properly on the indexing posts and doesn't jam the mechanism when loading/ejecting.
When aligning the tape path, a test tape will be needed as a reference. Actually, you want two - one recorded at the SP (2 hour) speed and another recorded at the EP (6 hour) speed. These do not need to be exorbitantly priced professional alignment tapes. A couple of recordings made on a known working VCR will get you close enough for most purposes. Do not use these same tapes for diagnosing or testing of mechanical problems, your VCR may be hungry and they may get eaten. For general video diagnosis including mechanical and tape eating problems, a bunch of sacrificial tapes is handy - advertising, promos, feature shorts - anything you do not care about but have been recorded on working VCRs. Very often they get mangled and you do not want to continue to use mangled tapes which may damage the VCR - in particular the video heads. However, once you have the VCR basically working, you will want to test it start to finish on a T120 cassette. This is because the reel hub size on those short video cassettes is not the same as a standard (most commonly used) T120 cassette and may mask problems if the VCR is mechanically marginal in some respects.
You will void the warranty - at least in principle. There are usually no warranty seals on a VCR so unless you cause visible damage or mangle the screws, it is unlikely that this would be detected. You need to decide. A VCR still under warranty should probably be returned for warranty service for any covered problems except those with the most obvious and easy solutions. It is usually very easy to remove the top and bottom covers on VCRs. For the top cover, there are usually some very obvious screws on the back or sides, and in rare cases on the top. There may be a couple of screws on the bottom as well that secure the top cover. For top loaders, you will probably need to remove the cassette holder lid - there will be two screws, perhaps hidden by rubber plugs. Once all the screws are out, the top cover will lift up or slide back and then come off easily. If it still does not want to budge, recheck for screws you may have missed. For the bottom cover, there are usually a half dozen or so screws around its perimeter and sometimes in the middle as well. There may be one or two grounding screws as well which are of different length and threads - these should go back in the same location from where they came. Bottom covers are usually simple sheet metal. In rare cases, you will need to remove the front panel to free the bottom cover (or vice-versa). Circuit boards may prevent access to the top or bottom of the tape transport. Usually, removal of a few screws (often marked with red paint or arrows on the circuit board) and perhaps pressing of a couple of snaps will permit the board to be swung up on a hinge out of the way. Front panels usually snap off, possibly requiring the removal of a few screws on top or bottom. Make notes of screw location and type and store the screws away in a pill bottle, film canister, or ice cube tray. When reassembling the equipment make sure to route cables and other wiring such that they will not get pinched or snagged and possibly broken or have their insulation nicked or pierced and that they will not get caught in moving parts. Replace any cable ties that were cut or removed during disassembly and add additional ones of your own if needed. Some electrical tape may sometimes come in handy to provide insulation insurance as well.
There are various sensors in a VCR that are light sensitive - it is not a safety interlock (though it acts this way in some VCRs) but a result of the way the tape start and end sensors operate. VHS tapes have a clear leader and trailer. An LED or light bulb poking up near the center of the cassette shine towards sensors at either side of the cassette. When light is detected the VCR assumes that it is at the appropriate end of the tape and shuts off (or rewinds if in PLAY mode when it senses the end depending on model). During servicing, a piece of opaque cardboard or other insulating material should be placed above the cassette basket if any strange behavior is detected that was not present with the cover in place. Not all VCRs are particularly sensitive external illumination.
This should be the first step in any inspection and cleaning procedure. Do not be tempted to use compressed air! I would quicker use a soft brush to carefully dust off the circuit boards and power supply. Work in such a way that the resulting dust does not fall on the mechanical parts. For the deck itself, using compressed air could dislodge dirt and dust which may then settle on lubricated parts contaminating them. High pressure air could move oil or grease from where it is to where it should not be. If you are talking about a shop air line, the pressure may be much much too high and there may be contaminants as well. A Q-tip (cotton swab) moistened with politically correct alcohol can be used to remove dust and dirt from various surfaces of the deck (in addition to the normal proper cleaning procedures for the guides, rollers, heads, wheels, belts, etc.)
We have all done this: a tiny washer or spring pops off and disappears from sight inside the guts of the unit. Don't panic. First - unplug the VCR if it is plugged into the AC. Remove the battery pack from a camcorder. Try to locate the part with a bright light without moving the VCR. You may have gotten lucky (yeah, right). Next, over an area where a dropped part will be visible (not a shag carpet!), try any reasonable means to shake it loose - upside down, a little gently tapping and shaking, etc. A hard surface is better in some ways as you might hear the part drop. On the other hand it may bounce into the great beyond. If this does not work, you have two options: 1. Assume that the part has landed in a place that will not cause future problems. There could be electrical problems if it is metallic and shorts out some circuitry or there could be mechanical problems if it jams some part of the mechanism. There is an excellent chance that the part will never cause any harm. What chance? I don't know, maybe 99%. It is not worth taking the unit to pieces to locate the part. You are more likely to damage something else in the process. Obtain a replacement and get on with your life. The exception is, of course, if you now begin experiencing problems you **know** were not there before. 2. Take the unit to pieces in an attempt to locate the part. For all you know, it may be clear across the room and you will never find it inside. If all the gymnastics have not knocked it loose, then it may be really wedged somewhere and will stay there - forever. If the VCR behaves normally, then in all likelihood it will continue to do so. To prevent this sort of thing from happening in the future you will no doubt be much more careful. Sure you will! Some suggestions to prevent ejection of an E-clip, split washer, or spring into the great beyond: * Construct a paper dam around the area. * Tie a thread or fine wire around the part before attempting to remove it. Keep this 'safety line' on until after it has been reinstalled, then just pull it free. * Keep one finger on the part as you attempt to pop it free. * Hold onto the part with a pair of needlenose pliers or tweezers while prying with a small screwdriver.
Thanks to Brian Siler (bsiler@PROMUS.com) for using his Snappy(tm) rig to capture the original photos. Please refer to the photo: Typical VHS VCR Tape Transport Components for parts identification. The following description applies to 99.9% of the VCRs in existence today. I have seen one that had a sideways loading mechanism - very weird. Looking at the unit from above with the front toward you: * Supply spindle - left hand side platform on which the supply tape reel (inside the cassette) sits. The edge which contacts the idler tire, and associated brake pad, should be cleaned. * Takeup spindle - right hand side platform on which the takeup tape reel (inside the cassette) sits. The edge which contacts the idler tire, and associated brake pad, should be cleaned. * Idler - assembly which swings between supply and takeup reels and transfers power to the appropriate reel to wind the tape up during play and record and often to drive FF and REW. This may use a rubber tire or a gear. * Idler tire - the black rubber ring on the outside of one part of the idler which actually contacts the reel edges. This is single most likely part to need replacement after a few years of use. Some VCRs use a gear instead of a tire, but the tire is most common, especially in older units. Clean and inspect - replace if in doubt. See VCR with Idler Tire for a typical tire-type idler assembly. Some VCRs use gears in place of rubber (as is the case with the VCR shown in the photo: Typical VHS VCR Tape Transport Components. Teeth can break off but these are generally quite reliable. Some high-end decks may have separate motors for reel rotation. * Roller guides - there are two, one on each side. These assemblies move from their retracted position toward front of machine to their loaded position for play and record. The white rollers should spin freely and be clean. When retracted, the roller guide assemblies will be slightly loose. However, when the tape is wound around the video head drum, they must be snug against the V-Stoppers - the brackets at the end of the tracks. Also on the same assembly are tilted metal guide posts - again one for each side. These sometimes fall out with obvious consequences. Proper functioning and adjustment of the roller guides is the most critical requirement for proper tracking. (However, do not touch their settings without being really sure that they are at fault and not until you have read the sections relating to tape path alignment.) Clean and inspect. * Roller guide tracks - combination of plastic and metal slots in which the roller guide assemblies slide during tape loading and unloading. Check to make sure there is still some healthy grease on the surfaces. If gummed up or excessively dirty, clean and relube with a dab of plastic-safe grease on each sliding surface. * Video head drum or upper cylinder - approximately 2.45 inches in diameter by .75 inches high. This rotating assembly contains the video heads (and HiFi audio and flying erase heads, if present). Stay away from this unit. as video heads are very delicate. If you must clean it, refer to the specific instructions on cleaning video heads elsewhere in this document. Video heads do not normally require cleaning despite what the cleaning tape people will have you believe. If you are not having video noise problems, they should be left alone. * Capstan - right side after tape exits from roller guide. The capstan is a shaft about 3/16" diameter which during play and record (and search) modes control tape movement forward or reverse when the pinch roller is pressed against it. Should be cleaned thoroughly to assure proper tape movement during play, record, and search modes. * Pinch roller - black rubber roller about 1/2" diameter, 3/4" high which spins freely and is pressed against the capstan during play, record, and search modes. It is constructed as a molded rubber sleeve fused to a metal roller on a small ball bearing. A hard, shiny, dried out pinch roller can lead to tape edge munching and erratic sound, speed, and tracking. Clean thoroughly. Inspect for cracked, hard, shiny, or otherwise deteriorated rubber and free and smooth rotation. Even if you have no obvious record or playback symptoms, if the pinch roller appears concave or with a distinct worn ridge, replacement is recommended - erratic behavior will soon be the result. A tape which runs off center due to a bad pinch roller may result in tape edge damage and over time can also alter the wear pattern of the audio/control head and various guide posts. * Audio/control Head Stack - between right roller guide (when tape is loaded around drum) and capstan. Includes magnetic heads for non-HiFi (linear) audio and synchronization control track. Should be cleaned since tracking and non-HiFi audio performance is critically dependent on its performance. * Back tension arm - left side just as tape exits cassette - this is coupled to a felt Back Tension Band and serves to maintain a constant tension on the tape during play, record, and forward search. Retracts toward cassette when tape is unloaded. Back tension is somewhat critical and may need adjustment after long use. * Various other fixed guide posts - vertical stationary metal posts which tape contacts. Should be cleaned but rarely need adjustment. The positions of these vary somewhat by manufacturer. * Full erase head - left side towards rear which tape passes over just before going around roller guide, guide post, and drum. Rarely causes problems. Clean. * Impedance roller - left side near full erase head. Freely rotating roller stabilizes tape movement. Some VCRs lack this component. Clean. * Half loading arm - right side near capstan/pinch roller. On VCRs with 'rapid or instant access transports' this helps to position the tape in the intermediate (half loaded) position. A similar arm is usually present in other VCRs and helps to position the tape around the pinch roller. Check for free movement. Clean. Lubricate bearing if sluggish. * Belts - various size black rubber bands - a typical VCR will have between 0 and 12 of these on top and bottom. Typical is 3 or 4. Most are of square cross section though an occasional belt may be flat or round. The belts will need replacement after a few years. Clean and inspect. Replace any belts that are hard, cracked, stretched, or flabby. A good belt will feel soft and rubbery without cracks or other signs of deterioration. It will return to its relaxed length instantly if stretched by hand about 25%. Belt kits are generally available by VCR model but individual belts can be ordered as well. In either case, this is very low cost maintenance which can make an absolutely huge difference in the happiness of your VCR. New belts can often restore a comatose VCR to perfect health. For additional information on replacement rubber parts, see the section: "Determining belt, tire, and pinch roller specifications".
(From Alex (ramjam@globalserve.net)): 1. To confirm that a worn idler tire is causing a malfunction, without disassembly, I use a product called "Rubber Renue" (M.G.Chemicals Ltd. 13-80 Hale Road, Brampton, ON L6W 3M1 Canada 416 454-4178). First I clean the tire with isopropyl alcohol (99%) then using the other end of the Q-tip I apply Rubber Renue. You don't need much, I have had the same 100 ml (3.4 oz.) bottle for over 6 years. What the product does is rejuvenates and conditions the rubber (read: makes *sticky*) as to allow normal or near normal operation. I don't recommend this as a permanent fix, though it can be, it is a great diagnostic tool and the whole procedure takes about five minutes. 2. To fix squeaky pulley shafts and collars I use a pipe cleaner (most smoke shops sell them) to clean the collars, I then use transmission fluid (the same stuff you put in your car) as a lubricant on the shaft. It's lightweight, it doesn't gum up, it's cheap and can be bought just about anywhere. Just remember not to use too much as it spreads easily, which can be disastrous in a VCR.
* VCR refuses to FF or REW and shuts off. * VCR shuts off entering PLAY or REC or at random during PLAY or REC. * VCR eats tapes. * VCR doesn't accept tapes or ejects them without cause. * Sound is wavery, fluctuating, or muddy. The cause for all of these is very often a bad idler tire or other dirty, worn, or tired rubber parts. See the section below: "General guide to VCR cleaning and rubber parts replacement". A VCR that just munched down your favorite tape is very likely only in need of a little tender loving care. WARNING: Don't turn a simple repair into a full length double feature. Most tires and belts come off without extensive disassembly. However, if your VCR is the exception, DO NOT remove anything to get at the rubber part that may be part of a critical timing relationship - racks or gears, for example - before fully understanding the implications of this action. In some cases, if a gear is rotated even one tooth from where it should be, there can be unforeseen and catastrophic consequences. See the section: "Mechanical relationships in VCRs" for more information before proceeding any further!
All the guideposts, wheels, and rubber parts of a VCR should be cleaned periodically - how often depends on usage. Of course, no one really does it unless something goes wrong. Do not attempt to clean the video heads until you follow the proper procedure given elsewhere in this document, you can break them - very expensive lesson. In most cases, they do not need attention anyhow. Q-tips and alcohol (91% medicinal is ok, pure isopropyl is better. Avoid rubbing alcohol especially if it contains any additives) can be used everywhere except the video heads. Just dry quickly to avoid leaving residue behind or damaging the rubber parts further. Cleaning may get your machine going well enough to get by until any replacement rubber parts arrive and to confirm your diagnosis. Things to clean: 1. Capstan and pinch roller. These collect a lot of crud mostly oxide which flakes off of (old rental) tapes. Use as many Q-tips (wet but not dripping with alcohol) as necessary to remove all foreign matter from the capstan (the shiny shaft that pulls the tape through the VCR for play and record). Just don't get impatient and use something sharp - the crud will come off with the Q-tips and maybe some help from a fingernail. Clean the pinch roller (presses against the capstan in Play, Record, and Search mode CUE and REVIEW) and until no more black stuff comes off. Use as many Q-tips as necessary until no more black gunk collects on Q-tip. If the pinch roller is still hard, shiny or cracked, it will probably need replacement. Many are available for about $6 from the sources listed at the end of this document. It is sometimes possible to put the pinch roller in an electric drill, drill press, or lathe, and carefully file off the hard shiny dried out rubber surface layer, but only use a last resort - and this fix is probably temporary at best. 2. Various guideposts including the roller guides (the white rollers on metal posts which are near the video head drum when in play or record mode). When in FF or REW, or with no tape present, these move on tracks to a position toward the front of the VCR. Note that the roller guides with the white rollers and tilted metal posts will be fairly loose when in the unloaded position (but you should not be able to lift them off the tracks). When actually playing or recording a tape, they will be snug against the stoppers at the end of the tracks. 3. Idler tire (idler swings between reels and transfers motor power to reels - clean until no more black stuff comes off. A dirty or worn idler tire is probably the single most common VCR problem. If the idler tire appears cracked, glazed, or dried out, it will need to be replaced. About $.50-$1.00. As a temporary measure, you can usually turn the tire inside-out and replace it. The protected inner (now outer) surface will grip well enough to restore functionality until a replacement tire arrives - and verify the diagnosis as to the cause of your problem. Also, the idler assembly includes a slip clutch. If this weakens, the idler may not have enough force to press on the reel table edges. If it becomes too tight, there may be audio, video, or crickled tape problems and/or excess wear of the idler tire. When in doubt, the entire idler assembly is often available as a replacement part. They can often be disassembled and adjusted if necessary. 4. Reel table edges - surface on the reel tables where the idler contacts. 5. Audio/control head (right side) and full erase head, (left side). Q-tips and alcohol are ok for these. 6. Anything else that the tape contacts on its exciting journey through your machine. 7. Rubber belts. Access to some of these will probably require the removal of the bottom cover. After noting where each belt goes, remove them individually (if possible) and clean with alcohol and Q-tips or lint free cloth. Dry quickly to avoid degrading the rubber from contact with the alcohol. If a belt is trapped by some assembly and not easy to remove, use the Q-tip on the belt and/or pulley in place. However, if it is stretched, flabby, or damaged, you will need to figure out how to free it. Make sure that there are no twists when a square cut belt or replacement is installed on its pulleys. On some models, you may need to unscrew circuit board(s) blocking access to either the top or bottom of the tape transport. Make notes of what went where - particularly different types of screws and routing of wires. Any belts that appear loose, flabby or do not return instantly to their relaxed size when stretched by 25% or so will need to be replaced and may be the cause of your problems. Belts cost about $.30-$2.00 and complete replacement belt kits are often available by model for $3.-$12. Meanwhile, the belts will function better once they are cleaned, maybe just enough to get by until your replacements arrive. 8. Video heads: READ CAREFULLY. Improper cleaning can ruin the expensive video heads. DO NOT attempt to clean the video heads without reading and following the procedure described in the section: "Video head cleaning technique". While VCRs should be cleaned periodically, the video heads themselves usually do not need cleaning unless you have been playing old or defective rental tapes which may leave oxide deposits on the tips of the delicate ferrite head chips. Unless you are experiencing video snow, intermittent color, or loss of or intermittent HiFi sound (HiFi VCRs only, the HiFi heads are located on the video head drum and for the purposes of cleaning, treated the same way) leave the video heads alone. If you really feel that video head cleaning is needed, refer to the sections on video head problem diagnosis and cleaning elsewhere in this document.Go to [Next] segment
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