For contact info, please see the Sci.Electronics.Repair FAQ Email Links Page.
Copyright ©; 1997-2021
Reproduction of this document in whole or in part is permitted if both of the
following conditions are satisfied:
1. This notice is included in its entirety at the beginning.
However, if the cover of the VCR needs to be removed, there will be a few
additional precautions though most of these disappear if the VCR is unplugged
from the electric outlet (or in the case of a camcorder, the battery pack
is removed.
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.
Since nearly everything described below can and should be done with the plug
pulled from the outlet, there is little danger to you electrically as long as
you stay away from the power supply (usually where the cord connects) where
some large capacitors may retain a charge for as much as few minutes.
There are, however, various sharp sheet metal brackets which will be out to
attach you if you reach into the bowels of the VCR. Just be aware of this
hazard as you poke and prod (but only where directed!).
To avoid damage to the VCR, don't turn anything you don't understand fully
and stay away from the video drum (the roughly 2.5 inch diameter cylinder
mounted on an angle (this is normal, don't use Vise Grips in an attempt
to straighten it out!!!). The reason is that the parts of the VCR that scans
the tape - the video heads - are very fragile being little chips of ferrite -
a brittle ceramic material.
We will not be responsible for damage to equipment, your ego, county wide
power outages, spontaneously generated mini (or larger) black holes, planetary
disruptions, or personal injury or worse that may result from the use of this
material.
All Rights Reserved
2. There is no charge except to cover the costs of copying.
SAFETY:
If all you are doing will be working on a video cassette, then common sense
use of small screwdrivers and sticky tape will be all that is needed. :)
DISCLAIMER
Once a VCR becomes hungry or a long neglected tape turns to a pile of what
looks more like adhesive tape, there is no guarantee that the situation can
be resolved with damaged to either the VCR or partial or total loss of
irreplacible family memories. For tapes you consider to be really valuable
(or just those Tom and Jerry cartoons you treasure!), consider a professional
video recovery service. They won't be cheap but will probably have a better
chance of success than you will if you've never seen the inside of a VCR or
cassette before.
Introduction
This section only deals with getting the cassette out without damaging either your (or the video store's) valuable recording or VCR.
Under no circumstances should you force anything - both your tape and your VCR will be history! If the rental tape really needs to be go back and you are unable or unwilling to risk going into your VCR, explain the situation to the video store - they would rather you get it out in such a way that it is not damaged just as much as you do.
First, see if the VCR just got into a confused state - pull the plug and patiently wait a minute or two. This will seem like an eternity but may reset the microcontroller and all will be well. These things happen.
If this is not successful, you will need to open up the VCR (unplug it first!) and attempt to cycle the mechanisms by hand. Probably, both the top and bottom covers will need to be removed. This will require a medium size philips screwdriver. There are usually 2 to 4 screws on top and 2 to 10 screws on the bottom. Don't be tempted to turn anything you see in there just yet!
CAUTION: Do not plug the VCR into the AC outlet while in the middle of this treament as there is no telling what it will do. The end result might be more of a mess than what you had originally! The VCR might in its infinite wisdom decide to complete the eject cycle but catch the tape on some guidepost or crinkle it in some other creative manner.
The following procedures assume that there are no broken parts, foreign objects, or other damage which might prevent manual cycling of the tape loading and cassette loading mechanism. (Inspect for toys and rocks.) Also note that some VCR designs use solenoids to engage various operations. This will complicate your task (to put it mildly) as locating and activating the proper ones at the appropriate time is, well, a treat.
Please refer to the photo: Typical VHS VCR Tape Transport Components for parts identification. (Photo courtesy of: Brian Siler (bsiler@PROMUS.com).) This VCR is shown in the fully unloaded position. The roller guides are in their retracted position. The cassette itself and cassette mechanism (called the basket or carriage) have been removed. Assuming that your cassette is in and down in the loaded position, its front-end would be just covering the roller guides, backtension arm, and capstan.
Depending on what the VCR was doing or attempting to do when it got confused, you may need to do both (1) and (2) or just (2). (For Panasonic and clone VCRs, see the section: Removing the cassette from Panasonic and clone VCRs.
It will take many revolutions - be persistent. If you feel any significant resistance or the roller guides move out toward the drum, turn the other way. The tape is fully unloaded when the roller guides are all the way into the cassette and the tape is straight across the cassette's stationary guideposts.
If turning the shaft is impossible, you can disconnect the wire leads going to the motor from the circuit board and apply 6 to 12 VDC from a battery, power supply, or wall adapter directly to the motor. It is essential to disconnect the motor completely to prevent damage to the circuitry in other parts of the VCR. Take care - reverse the connections if it seems to spin in the wrong direction and don't let it force anything. Motion should be smooth.
If a single motor performs both the tape loading and cassette loading functions, stop turning as soon as you see the cassette start to rise and read the next section before proceeding.
If you are not fully successful or if there is still a tape loop outside the cassette even once you have been turning for what seems to be an eternity, you can still try to eject the cassette but will need to be extra careful not to crinkle the tape as the cassette door closes with the tape sticking out. Before proceeding on in this case, try to find a way to turn one of the reels to pull that tape back in as this will make your task a lot easier. There may be an idler that swings between the two reels and this may be accessible from the bottom (the cassette will block it on top).
Sometimes, if for some reason the tape in the cassette is a bit loose when you go to insert it into the VCR, the tape may jump over a guide post or the pinch roller as the cassette is lowered into position. This tape will then get caught when the VCR goes to eject the cassette - it may come half way out and get hang up on the tape loop. The VCR then tries in vain to complete the eject sequence but gives up after a few seconds. It then either just shuts down or pulls the cassette back into position on the transport. If this happens, the tape is almost certainly damaged enough to be unusable and cutting the tape may be the easiest option. If you want to save what is on the tape, see the section: Recovering damaged or broken tapes.
On a top loader, there is usually a solenoid specifically for EJECT or a simple mechanical pushbutton. Once the appropriate lever is pressed, the cassette should pop up - hold the basket with one hand as you do this to prevent any exposed tape loop from being crinkled.
On a front loader, locate the cassette loading motor and begin turning it in the appropriate direction - this will be fairly obvious assuming there are no broken gear teeth or other broken parts and that something isn't totally jammed. If this is the main capstan motor, then just continue turning as in (1). Eventually the cassette should raise up and out.
As above, applying external low voltage power (6 to 12 VDC) to the motor *after* disconnecting it is an alternative if you cannot gain access to its shaft to turn it by hand.
If you have a tape loop, be extra careful not to catch it on any guideposts or obstructions as you remove the cassette. Then, wind it back into the cassette by turning one of the reels (you may have to depress the release button on the bottom of the cassette with a pencil - this is the small hole in the center near the label side.)
And in some cases, just turning the VCR upside-down and gently easing the cassette out will work. But as noted, don't force anything.
Assuming the tape is not torn and not badly crinkled, it should be fine. If it is severely damaged, refer to the section: Recovering damaged or broken tapes.
To determine if your VCR was made by Matsushita, search for its FCC number at: List of FCC ID numbers. One way to identify this mechanism is to remove the top cover (power off!): A large circuit board covers nearly everything but the area of the cassette and a white plastic circular knob like thing (great description, huh?) is visible poking though near the right hand side just beyond the cassette (DON'T touch or turn it!).
You will need to remove the bottom cover.
On this design where a single motor operates everything, there is a little tab next to the main gear (underneath near the capstan motor). Gently pressing this tab sideways (away from the gear) allows the mechanism to cycle through the various tape and cassette loading and unloading operations.
With the tab in the engaged position, turning the main motor or the big flywheel counterclockwise unloads the tape from the video heads, retracts the roller guides, and winds the tape back into the cassette, and then ejects the cassette itself. The tab will have to be engaged several times to accomplish all these tasks. DON'T force anything as it will move easily unless there is something binding or you reach the end of its travel. Take care that a loop of tape doesn't get caught behind a guide post or pinch roller. With care, the cassette will pop out as though nothing were wrong :-).
WARNING: If the loop of tape is badly crinkled, mashed, at all torn, or damaged in any other way such that it could catch the spinning video heads, throw it away. If you must save the material, see the section: Recovering damaged or broken tapes.
There is a hole in the bottom of the cassette about 1/4" in diameter in the middle approximately 1 inch from the label side (front). Depress this with a suitable tool (a pencil will usually suffice), and the reels will be free to turn. Carefully wind the tape back into the cassette. That's it!
CAUTION: Read the following in its entirely to avoid an expensive lesson. Improper cleaning can ruin your expensive video heads. The head chips are very fragile and just rubbing them in the wrong direction (NEVER use an up-and-down motion) can break them completely off.
Manual cleaning using the proper head cleaning sticks is best but requires that you gain access to the interior of your VCR - i.e., take off the cover.
If you do not want to do this, you can try a wet type head cleaning tape. I do not recommend the dry type as they are much more abrasive and may cause premature wear of your video heads especially if used regularly. When using the wet type cleaning tapes, follow the directions and - very important - wait sufficient time for everything to dry out
CAUTION: If you do not wait long enough, the conseqauences can be unfortunate (and impressive) - wads of tape wrapped around the drum and caught in places where no tape should tread. Damage to the heads can also result. Needle to say, that tape will be ruined.
To clean by hand, you will need what are called 'head cleaning sticks'. These are covered by chamois and are safest. DO NOT USE QTIPS (COTTON SWABS). These can catch on the ferrite cores and damage them or leave fibers stuck in the heads. QTips can be used for cleaning the other parts like the rollers and audio/control head but not the video heads.
To use the cleaning stick, moisten it with head cleaner or alcohol. Pure isopropyl is best, however, the 91% medicinal stuff is ok as long as you dry everything pretty quickly. Don't flood it as it will take a long time to dry and you run the risk of any water in the alcohol sitting on surfaces and resulting in rust (very unlikely, but don't take the chance).
WARNING: Do not use any strong solvents like acetone (nail polish remover), paint thinner, fuming sulphuric acid, etc. Some of these may eat at the adhesives or plastic components of your VCR.
Gently hold the flat portion of the chamois against the upper cylinder where it is joined to the lower (non-rotating) cylinder. Rotate the upper cylinder be hand so that the heads brush up against the moist chamois.
WARNING: DO NOT MOVE THE HEAD CLEANING STICK UP-AND-DOWN - you will break the fragile ferrite of the heads - $$$$. Side-to-side is ok as long as you are gentle.
Depending on how dirty your heads are, a couple of passes may be enough. Let everything dry out for at least 1/2 hour. This process can be repeated. However, one pass will usually do it.
In addition, inspect and clean the drum itself staying safely away from the video head chips. The five fine grooves in the drum help control the air bearing that the tape rides on and helps to stabilize tape motion. These should be clear of dirt and tape oxide (DO NOT use anything sharp or hard - the moistened head cleaning sticks will work).
WARNING: Don't be tempted to try to clean the heads when they are spinning while playing a tape. Professionals may have their favorite technique but just stick to the recommendations above until you have cleaned your 1000th VCR!
If it is only slightly crinkled, the tape may be salvageable (though it will never likely play without some dropouts). How serious is 'serious'? Hard to say but ironing may help. See the section: Uncrinkling a crinkled tape.
However, if it is broken - even partially, or stretched and scrunched, I recommend you throw it away (and make sure no one else can pull it out of the trash and ruin *their* VCR!).. An imperfect splice or seriously crinkled section of tape can shatter your video heads - the most expensive single part in a VCR. If it is something you really treasure, than what I would do is to follow the procedure below.
Note: If you have never seen the inside of a video cassette, try the following on a couple you really don't care about first so that if you screw up, there is no great loss. Too bad AOL doesn't send out Internet software on video cassettes, huh?
CAUTION: The video tape itself is really really thin and easily crinkled. Be very gentle when handling it and avoid touching the oxide (dull side) if at all possible.
Use the little plastic plugs that came from the garbage tape reels or some adhesive tape to connect the tape to the reels.
Filip (I'll buy a vowel) Gieszczykiewicz (filipg@repairfaq.org) is a little more definitive about this: "I find the destruction of it more fulfilling :-) ... put it in a paper bag and smash the life out of it with a big, heavy hammer - or a small ball hammer for an even higher satistfaction ratio :-) "
The idea is to never have a splice in a VHS cassette. (Even a seriously crinkled tape such as might result from a tape eating incident can damage the heads.) It is possible to splice safely but as noted, it can be quite costly if you don't get it quite right.
If you really don't want to go to all the effort of the transplant and the tape is not so badly damaged that there are ragged or torn sections, here is a simpler technique that is probably relatively low risk:
(From: Mark Whitis.)
This is the technique I have used for years on crinkled tapes. It is safer than ironing or using the edge of a desk and your hands never need touch the media.
It helps to have more than two hands but I usually end up using just two and maybe a spare body part to hold the pen against the reel lock release when necessary. The actual un-creasing part is easily done with two hands, one to hold the tape and hold the door open and one to operate the burnishing tool.
Use an ordinary Bic (or similar) ball point pen, clean and preferably new, as a burnishing tool. Use alcohol to clean pen, if necessary, and allow to dry. Because the pen is clean, smooth, soft, and round it makes an ideal burnishing tool and can't damage the tape unless there is abrasive dust on the tape itself.
After using this technique, the tape should be smooth enough to be safely played. There will be some visible degradation in the damaged section but it will play better than if you had not un-crinkled the tape.
I always use this technique before attempting to play the damaged section and before winding it back onto the reel (if the VCR has not already done so).
Just winding the damaged section back into the cassette and then FFing or REWing as appropriate to put several layers of tape on top of it may help. Leave it like that for a few days and then carefully return to the crinkled section to see how it is doing. WARNING: Do all this on a VCR that DOESN'T have an instant response transport so that there is no chance of the video heads contacting the damaged part of the tape. You may have to do this a few times.
Passing the damaged section (backing side) around a blunt edge (like a table top) back and forth a few times may help as well.
(From: Paul K. Sagi (paul_sagi@astro.com.my).)
I had a go at a seriously crinkled VHS tape that my mom was wanting to show her class at temple. I put the crinkled section between pieces of the kind of paper that is sold for some kind of cooking use, can't remember what it is called. I then ironed it (heat only, no steam) and it worked OK except a couple of seconds dropout."
(From: Steven Van Assche (steven.vanassche@bluebottle.com).)
CAUTION: Use with care!!
I use the following: Get your iron, the one used for T-shirts, not your soldering iron! ;-)
What I do:
The most important factor here is heat: Too hot and you will burn the tape instantly while too cold and nothing will happen. It is best to start from cold to warm, and slowly increase the heat until you see an improvement...
When you reassemble the cassette, take care to avoid crunching the tape under the hinged door - depress the unlock button on the side and lift it clear if needed.
-- end V1.36 --
