Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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Default VCR image only when fast-forwarding (tried cleaning heads)

Hi,

The VCR quit playing tapes (all of them), but the sound still works.
When fast forwarding, the picture is crystal clear (except for the
normal static bar). When I switch from fast-forward to play, the
picture goes to 3/4 static (where I can still make out the picture,
which is no longer fast-forwarding), for a half-second (or less),
before going to full static, then just blue.

I tried cleaning the heads, which had no effect.

The VCR is as ESA. Any ideas?

A note on head cleaning: Did I do it right? I must have spent an hour
on Google trying to find a picture of VCR heads IN a VCR, before giving
up. I had some VCR cleaning fluid and chamois cleaning sticks someone
left behind long ago. So I just opened it up and guessed. There's a
cylinder that has horizontal lines on the top half, with none at the
bottom. At two points 180 deg. apart, in the middle of the cylinder,
there are small openings. I assume those are the video heads. I moved
the cleaning stick back and forth horizontally over these two areas, as
I had read about (no pictures...). I tried this three times, checking
with a tape in between. No effect. I still only get an image while
fast-forwarding. (So I apparently didn't do additional damage...) I
checked the manual, and this is supposed to be a 4-head VCR. Are the
heads paired up, with two in each of those two small holes?

  #2   Report Post  
 
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tim:
Either the heads are still dirty or clogged..... or the heads are
damaged or broken. An improper or haphazard cleaning can easily damage
the fragile head chips.
A quick examination by a service shop tech can give you the answer....
many times a small shop can give you a fairly inexpensive diagnosis for
the price of a cleaning or less.... and if it just needs to be
cleaned, it will be done properly and safely by a shop tech.... and of
course, expect to be charged for a cleaning.... and then your VCR will
work properly.
electricitym
..
..
..

  #3   Report Post  
nolsar
 
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Try adjusting the tape guide posts, white plastic cylinders on chrome posts,
up or down may need tightening with small flat screwdriver or hex tool,
sometimes they become loose and the picture will be half missing.
wrote in message
oups.com...
tim:
Either the heads are still dirty or clogged..... or the heads are
damaged or broken. An improper or haphazard cleaning can easily damage
the fragile head chips.
A quick examination by a service shop tech can give you the answer....
many times a small shop can give you a fairly inexpensive diagnosis for
the price of a cleaning or less.... and if it just needs to be
cleaned, it will be done properly and safely by a shop tech.... and of
course, expect to be charged for a cleaning.... and then your VCR will
work properly.
electricitym
.
.
.



  #4   Report Post  
Sam Goldwasser
 
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"nolsar" writes:

Try adjusting the tape guide posts, white plastic cylinders on chrome posts,
up or down may need tightening with small flat screwdriver or hex tool,
sometimes they become loose and the picture will be half missing.


DON'T touch the alignment! I'd quicker go with clogged heads if it's
a 4 (or more) head VCR. Then, a different set of heads is used for
normal play and FF, and for different speeds. Have you tried playing
back tapes recorded at both SP and EP speed?

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.

wrote in message
oups.com...
tim:
Either the heads are still dirty or clogged..... or the heads are
damaged or broken. An improper or haphazard cleaning can easily damage
the fragile head chips.
A quick examination by a service shop tech can give you the answer....
many times a small shop can give you a fairly inexpensive diagnosis for
the price of a cleaning or less.... and if it just needs to be
cleaned, it will be done properly and safely by a shop tech.... and of
course, expect to be charged for a cleaning.... and then your VCR will
work properly.
electricitym
.
.
.

  #5   Report Post  
Laurence Payne
 
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On Tue, 20 Sep 2005 06:14:18 -0400, "nolsar"
wrote:

Try adjusting the tape guide posts, white plastic cylinders on chrome posts,
up or down may need tightening with small flat screwdriver or hex tool,
sometimes they become loose and the picture will be half missing.


Don't fiddle with those unless you know exactly what you're doing and
have the necessary equipment. You'll only make things a lot worse.

Are you sure you're actually cleaning the heads, not just polishing
the drum? Again, if you don't know what you're doing, don't do
anything. A professional clean is cheaper than new heads.


  #6   Report Post  
nolsar
 
Posts: n/a
Default

Try adjusting the tape guide posts, white plastic cylinders on chrome
posts,
up or down may need tightening with small flat screwdriver or hex
tool,
sometimes they become loose and the picture will be half missing.
wrote in message
oups.com...
tim:
Either the heads are still dirty or clogged..... or the heads are
damaged or broken. An improper or haphazard cleaning can easily

damage
the fragile head chips.
A quick examination by a service shop tech can give you the

answer....
many times a small shop can give you a fairly inexpensive diagnosis

for
the price of a cleaning or less.... and if it just needs to be
cleaned, it will be done properly and safely by a shop tech.... and

of
course, expect to be charged for a cleaning.... and then your VCR

will
work properly.
electricitym
.
.
.


  #7   Report Post  
Sam Goldwasser
 
Posts: n/a
Default

"nolsar" writes:

Try adjusting the tape guide posts, white plastic cylinders on

chrome posts,
up or down may need tightening with small flat screwdriver or hex

tool,
sometimes they become loose and the picture will be half missing.

DON'T touch the alignment! I'd quicker go with clogged heads if it's
a 4 (or more) head VCR. Then, a different set of heads is used for
normal play and FF, and for different speeds. Have you tried playing
back tapes recorded at both SP and EP speed?

--- sam | Sci.Electronics.Repair FAQ Mirror:
http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents:
http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ:
http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites:
http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the
excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header
above is
ignored unless my full name is included in the subject line. Or, you
can
contact me via the Feedback Form in the FAQs.

wrote in message
oups.com...
tim:
Either the heads are still dirty or clogged..... or the heads are
damaged or broken. An improper or haphazard cleaning can easily

damage
the fragile head chips.
A quick examination by a service shop tech can give you the

answer....
many times a small shop can give you a fairly inexpensive diagnosis

for
the price of a cleaning or less.... and if it just needs to be
cleaned, it will be done properly and safely by a shop tech.... and

of
course, expect to be charged for a cleaning.... and then your VCR

will
work properly.
electricitym
.
.
.


  #8   Report Post  
 
Posts: n/a
Default


wrote:
tim:
Either the heads are still dirty or clogged..... or the heads are
damaged or broken. An improper or haphazard cleaning can easily damage
the fragile head chips.
A quick examination by a service shop tech can give you the answer....
many times a small shop can give you a fairly inexpensive diagnosis for
the price of a cleaning or less.... and if it just needs to be
cleaned, it will be done properly and safely by a shop tech.... and of
course, expect to be charged for a cleaning.... and then your VCR will
work properly.
electricitym
.
.
.


I'm not taking this thing to a repair shop. It was junk right out of
the box, and the person who bought it didn't keep the box or receipt.
I suggested taking it back a week after it was purchased (again it's an
ESA). It would constantly not fully rewind tapes, you would have to
stop and then hit rewind again a couple times on most tapes. The time
it takes to spit out a tape is extremely annoying, who know what the
*** it's doing before it just ejects the stupid tape. About 4 months
later is quit recording - everything came out as just noise, like you
are tuned to a non-existant channel - and we had recorded with it
infrequently. Now it has quit playing our daughters cartoon tapes,
which is its main use. (It's only a few months old.) I'd just throw the
thing away right now, except the TV gets broadcast channels better when
the antenna goes through the VCR - the ONLY thing that still works. I'm
looking for a replacement. If I can't easily fix it, it's going in the
trash.

  #9   Report Post  
 
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nolsar wrote:
Try adjusting the tape guide posts, white plastic cylinders on chrome posts,
up or down may need tightening with small flat screwdriver or hex tool,
sometimes they become loose and the picture will be half missing.
wrote in message
oups.com...
tim:
Either the heads are still dirty or clogged..... or the heads are
damaged or broken. An improper or haphazard cleaning can easily damage
the fragile head chips.
A quick examination by a service shop tech can give you the answer....
many times a small shop can give you a fairly inexpensive diagnosis for
the price of a cleaning or less.... and if it just needs to be
cleaned, it will be done properly and safely by a shop tech.... and of
course, expect to be charged for a cleaning.... and then your VCR will
work properly.
electricitym
.


There doesn't seem to be a way to adjust that. Like the heads, I can't
find a picture of "guide posts" with Google. Are you talking about
those two pieces that move to push the tape against the cylinder? Those
seem to be fixed, and I don't see any other parts that could effect the
tapes position on the cylinder.

  #10   Report Post  
 
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DON'T touch the alignment! I'd quicker go with clogged heads if it's
a 4 (or more) head VCR. Then, a different set of heads is used for
normal play and FF, and for different speeds. Have you tried playing
back tapes recorded at both SP and EP speed?


The VCR quit recording 3-4 months ago, and there isn't another VCR
around to make a tape to test SP/EP. This VCR was junk right out of the
box - see my reply to the first reply in this thread.



  #11   Report Post  
 
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Are you sure you're actually cleaning the heads, not just polishing
the drum? Again, if you don't know what you're doing, don't do
anything. A professional clean is cheaper than new heads.


I don't know. That's why I included all those details. Are the heads
180 deg apart in the middle of the drum? There are only two "holes" in
the drum, and it's supposed to be a 4-head VCR.

  #12   Report Post  
sofie
 
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????? why would anyone tell a non-technical person who is having difficulty
with a simple task of cleaning the heads tell them to adjust the roller
guides or alter any other critical alignment????
More than likely the heads are still dirty or clogged.... or have been
damaged by improper cleaning or a defective tape?
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -


"nolsar" wrote in message
eenews.net...
Try adjusting the tape guide posts, white plastic cylinders on chrome
posts,
up or down may need tightening with small flat screwdriver or hex
tool,
sometimes they become loose and the picture will be half missing.
wrote in message
oups.com...
tim:
Either the heads are still dirty or clogged..... or the heads are
damaged or broken. An improper or haphazard cleaning can easily

damage
the fragile head chips.
A quick examination by a service shop tech can give you the

answer....
many times a small shop can give you a fairly inexpensive diagnosis

for
the price of a cleaning or less.... and if it just needs to be
cleaned, it will be done properly and safely by a shop tech.... and

of
course, expect to be charged for a cleaning.... and then your VCR

will
work properly.
electricitym
.
.
.




  #14   Report Post  
Leonard Caillouet
 
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Bad advice. Unless one understands the principles of operation quite well,
tweaking alignment on a VCR is almost certainly not going to solve a
problem. If the guides are loose, that needs to be fixed, not just
adjusted. Likely still a clogged head or a damaged head.

Leonard

"nolsar" wrote in message
...
Try adjusting the tape guide posts, white plastic cylinders on chrome
posts,
up or down may need tightening with small flat screwdriver or hex tool,
sometimes they become loose and the picture will be half missing.
wrote in message
oups.com...
tim:
Either the heads are still dirty or clogged..... or the heads are
damaged or broken. An improper or haphazard cleaning can easily damage
the fragile head chips.
A quick examination by a service shop tech can give you the answer....
many times a small shop can give you a fairly inexpensive diagnosis for
the price of a cleaning or less.... and if it just needs to be
cleaned, it will be done properly and safely by a shop tech.... and of
course, expect to be charged for a cleaning.... and then your VCR will
work properly.
electricitym
.
.
.





  #15   Report Post  
Kevin Buhr
 
Posts: n/a
Default

writes:

When fast forwarding, the picture is crystal clear (except for the
normal static bar). When I switch from fast-forward to play, the
picture goes to 3/4 static (where I can still make out the picture,
which is no longer fast-forwarding), for a half-second (or less),
before going to full static, then just blue.


The problem you described certainly sounds like dirty heads, and guck
that gets into heads can sometimes be difficult to remove, so it's not
all that unusual that your first attempt at cleaning didn't do the job.

A note on head cleaning: Did I do it right? I must have spent an
hour on Google trying to find a picture of VCR heads IN a VCR,
before giving up.


Try
http://images.google.com and search for vcr heads.

So I just opened it up and guessed. There's a cylinder that has
horizontal lines on the top half, with none at the bottom. At two
points 180 deg. apart, in the middle of the cylinder, there are
small openings. I assume those are the video heads.


Yes, that's where the heads are. As you guessed, many 4-head VCRs
have two openings with two heads each.

I moved the cleaning stick back and forth horizontally over these
two areas, as I had read about (no pictures...).


I've personally found the "dry paper" method very effective for
removing really stubborn dirt. In the usual version, one presses a
dry strip of plain white (copier or laser printer) paper against the
drum and applies moderate-to-strong pressure while turning the drum by
hand back and forth to bring the heads across the paper horizontally.

In the "I don't care if I break this crappy VCR" variation that I use,
I press the strip of paper against the drum while the tape is playing
and the drum is spinning normally. In using this version, one must
pay attention to which way the drum is spinning (because catching the
edge of the paper with a head would be bad) and to the pointy bits on
top of the drum (which are flying around at 1800 RPM ready to shred an
unwary knuckle).

A note on head cleaning: Did I do it right? I must have spent an
hour on Google trying to find a picture of VCR heads IN a VCR,
before giving up.


Try:

http://images.google.com/

and search for "vcr heads". Also, see the VCR FAQ he

http://www.repairfaq.org/sam/vcrfaq.htm

which has a whole chapter devoted to video heads including a
description of the dry paper method.

--
Kevin


  #16   Report Post  
Gene E. Bloch
 
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wrote in
oups.com:


wrote:
tim:
Either the heads are still dirty or clogged..... or the heads are
damaged or broken. An improper or haphazard cleaning can easily
damage the fragile head chips.
A quick examination by a service shop tech can give you the
answer.... many times a small shop can give you a fairly
inexpensive diagnosis for the price of a cleaning or less....
and if it just needs to be cleaned, it will be done properly and
safely by a shop tech.... and of course, expect to be charged for
a cleaning.... and then your VCR will work properly.
electricitym
.
.
.


I'm not taking this thing to a repair shop. It was junk right out
of the box, and the person who bought it didn't keep the box or
receipt. I suggested taking it back a week after it was purchased
(again it's an ESA). It would constantly not fully rewind tapes,
you would have to stop and then hit rewind again a couple times on
most tapes. The time it takes to spit out a tape is extremely
annoying, who know what the *** it's doing before it just ejects
the stupid tape. About 4 months later is quit recording -
everything came out as just noise, like you are tuned to a
non-existant channel - and we had recorded with it infrequently.
Now it has quit playing our daughters cartoon tapes, which is its
main use. (It's only a few months old.) I'd just throw the thing
away right now, except the TV gets broadcast channels better when
the antenna goes through the VCR - the ONLY thing that still
works. I'm looking for a replacement. If I can't easily fix it,
it's going in the trash.


Sounds like you've got it figured out :-)

I would bet money (a dollar or two only) that the heads or their
associated wire leads or amplifiers have died. As one poster pointed
out, there are separate heads for different speeds, which would
explain why FF & REW still show a picture.

Looks like it's time to find a new one and hope it's better made.

Gino

--
Gene E. Bloch (Gino)
letters617blochg3251
replace the numbers by "at" and "dotcom"
  #17   Report Post  
Ken G.
 
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To get those heads clean put in a good movie get it playing then hold an
ordinary pencil erasor against the gap on the spinning heads somewhere
at the back where no tape is in the way .

  #18   Report Post  
Ken Weitzel
 
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Ken G. wrote:
To get those heads clean put in a good movie get it playing then hold an
ordinary pencil erasor against the gap on the spinning heads somewhere
at the back where no tape is in the way .



Hi Ken...

You have a real good name, but I'd sure like to disagree with you
anyway

I suggest that if you do that, you'll instantly destroy both the
heads and the 'good movie'.

Clean them properly and thoroughly instead. Piece of chamois,
little bit of isopropyl alcohol. Clean gently, look at the gap with
a good magnifying glass and flashlight. Repeat as necessary.

Give it a few minutes to dry before putting a tape in it.

Take care.

Ken

  #19   Report Post  
 
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Agree fully. A pencil eraser on the heads, spinning or not, will
usually result in destroyed head chips.....
electricitym

  #20   Report Post  
Ken G.
 
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You are both wrong . I have done this more times than i can remember on
very stuborn dirty heads . You dont force the erasor in there like
shoveling dirt .. you set it on there very light and let it rub for a
bit and watch the picture come back .
Have you ever tried it ?? no .. so you dont know .
It does not hurt the movie tape either .

Alcohol is useless to clean anything its just like using water .. throw
it out and forget it thats why many people dont get vcr heads clean .

The little heads on vcrs are only a problem if the rub up &down across
the gap instead of with the gap or push to hard and gouge . They will
not melt or absorb anything . I have repaired vcr`s sence the beginning
of the boat anchor top loads and work on brand new stuff of today and
not a drop of alcohol around .



  #21   Report Post  
Leonard Caillouet
 
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It may work, but why use a dry method that is likely to leave little bits of
eraser in the unit when you can use a chamois or other cleaning products
that will hold alcohol and leave no residue. Why take the risk?

As for alcohol not being an effective cleaner, I have to differ. It is a
lot better than water or dry methods. What do you use to clean the ridges
of oxide off of the capstan? I have cleaned many hundreds of VCRs, also
since the earliest days of the product, and have found denatured alcohol or
isopropanol to be very effective.

Leonard

"Ken G." wrote in message
...
You are both wrong . I have done this more times than i can remember on
very stuborn dirty heads . You dont force the erasor in there like
shoveling dirt .. you set it on there very light and let it rub for a
bit and watch the picture come back .
Have you ever tried it ?? no .. so you dont know .
It does not hurt the movie tape either .

Alcohol is useless to clean anything its just like using water .. throw
it out and forget it thats why many people dont get vcr heads clean .

The little heads on vcrs are only a problem if the rub up &down across
the gap instead of with the gap or push to hard and gouge . They will
not melt or absorb anything . I have repaired vcr`s sence the beginning
of the boat anchor top loads and work on brand new stuff of today and
not a drop of alcohol around .



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