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Free Vcr service info
10 MOST COMMON PROBLEMS
1)Snowy screen
2)Distorted picture
3)Lines in picture
4)VCR eats tapes
5)Tape does not play
6)Tape does not rewind or f-forward
7)Turning tracking knob has no effect
8)Cassette won't eject
9)Poor audio
10)No power
[HEAD CLEANING] [LUBRICATION] [SYMPTOMS] [TAPE ALIGNMENT]
WARNING---(There is up to 120 Volts inside the VCR..!! Do not attempt to go poking inside the VCR chassis when it is plugged in as serious damage to the unit may result, or shock to yourself causing serious injury. If you are not experienced in this type of equipment you should let the service center perform the repairs.)
INTRODUCTION:
Many VCR owners experience problems of some sort from time to time.
In most case's the VCR just needs a good cleaning. If a cleaning does not
restore the machine to normal operation then you have to dig a little deeper.
This trouble shooting guide is layed out for the novice person who has
some basic technical know how. If you feel you can not perform some of
the tasks outlined in this guide then by all means take the VCR to a reputable
shop. The mechanisms and electronic components are
quite delicate so be carefull when poking around inside the
chassis. Anyone can perform these simple procedures with the basic materials
and tools. Many of the maintenance,cleaning and adjustments tasks performed
by yourself would cost anywhere form $40 to $60 if a repair center
performed the repairs. Sometimes a poor quality picture is observed when
playing tapes. A good quality head cleaner can restore the picture. But
these head cleaners are abrasive by nature and can wear out the
video heads in the long run. They are a band aid solution. The use of these
tapes once every six months is more than enough in my experience. This
is where the manual cleaning comes in first step is to remove the top cover
which is normally attached by a couple phillips screws.
The first step you should take when you have removed the top cover
is check the loading bay,thats where the tape is inserted into the machine.
A lot of dust,hair,dirt,food particles,animal hair etc.reside in
this area. It is esential to clean this area very well,when a tape is inserted
into the machine it picks up all this dirt and eventually ends up around
the video heads. I recommend a light cleaning in this area periodically.
This avoids dirt from been lodged inside the VCR.
The basic service materials needed are Isopropanol 99% alcohol----grease----
preferably silicone variety----sewing machine oil is best and Electronic spray
cleaner. Most items can be purchased at your local hardware store
for about $12 and you will have enough cleaner to perform many services.
That is inexpensive considering a repair shop could charge $40 to $60.
VIDEO HEAD CLEANING:
Tip,never play a tape in the VCR until all the alcohol has evaporated
or the machine will eat the tape.
Many VCR service manuals recommend video head cleaning using a chamios
or sponge style q-tip,but what can happen cleaning this way is you can
embed more dirt into the head. In my years of servicing VCR's I have never
used this method. My personal VCR is over ten years old and the picture
quality is still very good. It has approximately 7000 hours use and I have
never replaced a part. I use the electronic spray cleaner for head cleaning.
Hold the nozzle about two inches away from the head and give it a quick
blast,spin the head and spray the other heads. You may have to repeat this
procedure a couple times depending how clogged the heads are. Should you
not notice a remarkable improvement then there is a possibility that the
video heads are damaged.
You should never come into contact with the video heads using a q-tip.
The q-tip has fine strands of cotton that can tangle around the heads and
cause damage. The q-tips are used for general cleaning of the rollers,pulleys
etc.
fig.3
below shows a typical video head,the exposed slot in the center
is where the head resides.
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LUBRICATION:
Oiling and greasing
the VCR is just as important as any other machine that has many moving
parts. There are many areas to grease and oil. For the inexperienced person
the easiest way to find out where to lubricate is to spot the old grease
on the mechanisms. Most grease from the factory is either blue or white.
All you have to do is give these areas a little dab of fresh grease. Don't
over do it. Sometimes to much grease can cause problems,it may smear onto
the rubber parts Creating slippage,then you have to go through the process
of removing all the grease and that is not easy.
To remove the bottom cover simply stand the VCR on it's side,you will
notice a metal cover attached by some phillips screws. The main belt and
other mechanisms are located here.
Check the belt for cracks and sloppiness. If the belt appears normal
then remove it and clean with alcohol same goes for all the pulleys that
the belt weaves around. If a new belt is required then your local electronic
supplier should have it. Most rubber parts are priced at about $2.
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SYMPTOMS
------------------------------------------------------->PROBABLE CAUSES
1) Snowy screen------------------------------------------------>
Dirty heads
2) Distorted picture-------------------------------------------->
Dirty heads,bad tape,tape align.
3) Lines in picture------------------------------------------------>
Tape align,pinch roller
Belt or Idler
4) VCR eats tapes----------------------------------------------->
Belt or idler, pinch roller
5) Tape does not play------------------------------------------->
Slipping belt, pinch roller, dirty Idler
6) No rewind or fforward---------------------------------------->
Bad Idler, worn belt
7) Tracking knob has no effect------------------------------->
Tape align,clogged heads,belts
8) Cassette won't eject---------------------------------------->
Cassette jammed, load motor belt
9) Poor audio---------------------------------------------------->
Poor belts, bad tape, audio head adj.
10) No power----------------------------------------------------->
Circuitry, wall outlet, blown fuse
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BASIC SERVICE NOTES:
You will notice that most of the problems are caused by dirty heads,main
belt,Idler tire,pinch roller and the load belt. We won't go into the
more serious problems because that is beyond the scope of this guide. When
these parts and mechanisms act up they account for about 90% of the problems.
As I mentioned earlier a good cleaning of all the heads and rubber
parts is the first step. Then and only then should you proceed to perform
any adjustments. Having a jammed tape sometimes is a cause of something
more serious. A typical load motor and belt are shown in Fig.#4 below.
If your unit is jammed then try to turn the loading belt by hand. Or
flip the VCR up and try hand cycling it from here. Most times the cassette
will eject. Perform this procedure with the VCR unplugged. After the tape
is removed check the belt for wear. If that appears normal then insert
a tape again and watch the operation of the load motor. If the belt slips
then replace it. If the motor is dead then a new one is worth considering.
Also check that the gears under neath are not binding. Parts binding
are not that common but they can cause a lot of aggravating head scratching.
Fig.#2 below shows a typical Idler assembly and tire. The tire can be
removed easily just by prying it off with a blunt object. Check the tire
for cracks. Clean as required allthough removing the tire is not essential
for
Cleaning. This is the assembly that provides tape movement ,play,fforwrd,and
rewind. The pinch roller as well serves this
function. Fig.#1 below shows a typical pinch roller.
Clean the pinch roller thoroughly you will notice a lot off tape residue
on the q-tip,if the machine has not had a recent cleaning in this area
you will use up about 10 Q-TIPS in doing so. In front of the pinch
roller you will notice a bright shiny shaft,this is the capstan shaft. Clean
this shaft as well. At the base of the shaft you will notice a plastic
washer,if possible lift it up and apply a few drops of oil. Oiling this
part is very important. What you are doing is oiling the bearing
of the capstan motor. I would recommend servicing these components at least
once every six months. This is a very CRUCIAL MECHANISM and
of the VCR. It is basically the heart of the unit. Fig.below
shows a typical audio head. It consists of two parts,the actual audio portion
and the controll track function. Sometimes adjusting this head can restore
picture quality. You will notice a large bevelled brass screw in front
of the head or just a phillips screw,turning this screw will give you the
final adjustment. Do not adjust the other screws it is not necessary.
TAPE ALIGNMENT:
From the photo you will notice the basic tape path around the heads
and other parts. If the VCR needs a tape path adj. Insert a known good
tape to perform the tape path alignment. If your machine has a manual tracking
adjustment,place the knob dead center. If it is automatic tracking then
continue on. Either with a screw driver or allen wrench slowly turn the
left spindle counter clockwise.
. Pay close attention to the TV,you should notice the picture changing,with
a line on the bottom or the top,or the picture may totally improve. Either
way it won't take long to get the feel for adjusting the spindles. If the
left side shows no improvment proceed with the right side.
Be carefull when adjusting the right side the tape can start creasing.
If it starts creasing back off the screw slightly until the tape is just
on the video head drum ledge. You may have to go back and forth a few times
until the picture on the TV clears up. As mentioned earlier try adjusting
the audio head first you may see instant results.
If after doing the head adjustments and the picture returns to normal,you
may notice some old tapes do not play as well. That's because the VCR was
dirty and out of adjustment at the time. At times when you play your friends
tapes you can never adjust the tracking control to obtain a good picture.
Hardly no two machines are alike their adjustments are unique to each
individual unit.
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Tips
Don't store tapes laying flat,stand them on end.
Don't position the VCR near a heat source.
Make sure all cable connections are proper.
Dust the VCR weekly.
Always store tapes inside their covers.
Tapes should be kept away from magnetic sources,TV's,speakers.
Don't enclose the VCR inside a cabinet,it needs space to ventilate.
The three most common factors affecting VCR performance are heat, moisture
and dust!
OVERVIEW:
All the adjusment and service techniques discussed here are the basics.
If after permorming all these steps and the picture does not clear up then
I would recommend take your VCR to a reputable shop.
Many other service techniques involve jigs,meters etc. The repair shops
have all the necessary equipment,resources and
Service manuals and schematic diagrams. To go any further is pointless
unless you are experienced repairing electronic equipment. 90% of
the time this guide will follow you through the basic service techniques
therefore saving you a good sum of money.
You can also repair VCR's for friends and family,thus saving them money.
Make sure to grease up the loading tray where the tape is inserted. There
are a few gears and sliders that need grease. If a serious problem arises
it may not be worth the cost to have it repaired. Case in point the older
VCR's are very well built a majority of the parts are metal where the newer
ones contain much more plastic. Most fuses are located at the rear of the
VCR where the power supply is located.
Always change the fuse with the same rating. There again if the VCR
keeps blowing fuses for no apparent reason more than likely it is associated
with the power supply or electronic circuitry.
(fig.1) Pinch rolls
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(fig.2) Spindle & Idler Assy
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(fig.3)Video head
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(fig.4) Load motor
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.:TYPICAL TAPE PATH OF A VHS VIDEO RECORDER:.
[HEAD CLEANING] [LUBRICATION] [SYMPTOMS] [TAPE ALIGNMENT]
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