Hi,

I have an old (I believe it was made around 1990/91ish) VCR. It's an
SVHS model - a Sanyo VHR-S700E (Stereo, PAL; I'm in the UK). I'm trying
to repair this vcr but I can't pinpoint exactly what the trouble is or
where I should look.

These are the problems:

* The VU LEDs don't light up at all ( they should light up to show the
volume levels; so far I've never seen them light up at all).

* The tape refuses to rewind, forward wind or play - the video tries to
but aborts the attempt.

There is another problem which I will come to in a moment.

First of all I thought that the second problem (regarding forward wind,
etc) might have been the capstan and that it might have ceased up or
needed oiling. I tried to do this with some sweing machine oil but it
seems to have had no effect (though I did this with the capstan still in
the machine).

However the LED problem points to (I'm guessing) a possible power
supply. Here is a picture of the inside of the VCR with the cable (I'm
guessing) carries the power for the LEDs; there's a ribbon cable that
connects nearby I guess this carries the signals to light up which LEDs
need to be lit;

http://img21.exs.cx/img21/9621/11142.jpg

You can see another picture of the power supply section here - note the
power supply is hard to get to and most of it inside a metal can:

http://img21.exs.cx/img21/9408/11143.jpg

There is a third problem though. I've noticed while I've had the video
apart that any usage of the tape (eg trying to wind forward, back, etc)
I have found one chip near the bottom of the capstan (on the underside
of the video) seems to get very hot very quicky. Here's a pictu

http://img21.exs.cx/img21/7159/3a4.jpg

I'm guessing the big wheel in that picture with the belt on it is the
underside of the capstan.

Incidentally, here are some pictures of the capstan:
http://img21.exs.cx/img21/8303/11144.jpg
http://img4.exs.cx/img4/1299/13031.jpg

And the left hand side of the VCR with the non-functioning VU meters:
http://img4.exs.cx/img4/7922/13032.jpg

Can anyone figure out what the problem is exactly? Are all these faults
seperate or interlinked in some way? I'm guessing this might all be down
to a power supply problem but where do I start looking? Does the fact
the chip gets hot mean it is dead or just being fed bad voltages?



Thanks for any help.

ljones

"ljones" wrote in message
...
|
| Hi,
|
| I have an old (I believe it was made around 1990/91ish) VCR. It's an
| SVHS model - a Sanyo VHR-S700E (Stereo, PAL; I'm in the UK). I'm trying
| to repair this vcr but I can't pinpoint exactly what the trouble is or
| where I should look.
....
| First of all I thought that the second problem (regarding forward wind,
| etc) might have been the capstan and that it might have ceased up or
| needed oiling. I tried to do this with some sweing machine oil but it
| seems to have had no effect (though I did this with the capstan still in
| the machine).
....

Sewing machine oil? Might as well shotgun it to death now.

N

NSM wrote:
"ljones" wrote in message
...
|
| Hi,
|
| I have an old (I believe it was made around 1990/91ish) VCR. It's an
| SVHS model - a Sanyo VHR-S700E (Stereo, PAL; I'm in the UK). I'm trying
| to repair this vcr but I can't pinpoint exactly what the trouble is or
| where I should look.
...
| First of all I thought that the second problem (regarding forward wind,
| etc) might have been the capstan and that it might have ceased up or
| needed oiling. I tried to do this with some sweing machine oil but it
| seems to have had no effect (though I did this with the capstan still in
| the machine).
...

Sewing machine oil? Might as well shotgun it to death now.

N





I found a FAQ on the internet which mentioned doing this and not to use
something like WD40. It suggested (from memory) using a thicker oil or
lubricant, not WD40 but sewing machine oil or machine oil.

I do notice that with the brake disengaged the capstan moves quite
freely by hand - but how free is free? I don't know if it moves enough.

ljones writes:

NSM wrote:
"ljones" wrote in message
...
|
| Hi,
|
| I have an old (I believe it was made around 1990/91ish) VCR. It's an
| SVHS model - a Sanyo VHR-S700E (Stereo, PAL; I'm in the UK). I'm trying
| to repair this vcr but I can't pinpoint exactly what the trouble is or
| where I should look.
...
| First of all I thought that the second problem (regarding forward wind,
| etc) might have been the capstan and that it might have ceased up or
| needed oiling. I tried to do this with some sweing machine oil but it
| seems to have had no effect (though I did this with the capstan still in
| the machine).
...
Sewing machine oil? Might as well shotgun it to death now.
N


I found a FAQ on the internet which mentioned doing this and not to
use something like WD40. It suggested (from memory) using a thicker
oil or lubricant, not WD40 but sewing machine oil or machine oil.

I do notice that with the brake disengaged the capstan moves quite
freely by hand - but how free is free? I don't know if it moves enough.



If you tried lubricating it and nothing much changed, that wasn't the problem
(whether you made it better or worse doesn't matter for this conclusion!).

Since I believe you had multiple symptoms, if they all happened at the same
time one must search for a common problem. It could all be power supply
related.

If the machine was sitting around for a couple years and now has these
problems, then they might be unrelated.

First, do the cleaning and checking in the FAQ.

Check the power supply voltages at standstill and while it's trying to
move the tape.

Sorry, I don't recall the other specific problems.

--- 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 is ignored.
To contact me, please use the feedback form on the S.E.R FAQ Web sites.

"ljones" wrote in message
...
| NSM wrote:

| Sewing machine oil? Might as well shotgun it to death now.

| I found a FAQ on the internet which mentioned doing this and not to use
| something like WD40. It suggested (from memory) using a thicker oil or
| lubricant, not WD40 but sewing machine oil or machine oil.

WD-40 is not a lubricant - it's a rust penetrator. Sewing machine oil often
contains solvents or kerosene. Lubricants for electro mechanical devices
should be the ones recommended by the manufacturer, unless you are very
skilled and experienced in which case the brave may substitute.

| I do notice that with the brake disengaged the capstan moves quite
| freely by hand - but how free is free? I don't know if it moves enough.

Technicians use special equipment which can measure the torques etc. for
these devices.

Always fix the electrical problems first - the VU meters etc. It's possible
that this indicates why the rest doesn't work. These things are a nightmare
of motors, clutches, brakes etc., and if the power supply is faulty it's no
surprise things don't work right.

N

Thanks for that, but should I just take the entire power supply right
out of the VCR to test it, or should I try to do it within the VCR
first? The only problem is half of it seems to be mounted in a
hard-to-get-to tin box x.x

thanks

ljones

ljones writes:

Thanks for that, but should I just take the entire power supply
right out of the VCR to test it, or should I try to do it within the
VCR first? The only problem is half of it seems to be mounted in a
hard-to-get-to tin box x.x

You'll want to test it under normal load. So, if you can get at its outputs,
it should be left in the VCR. Of course, knowing WHAT the proper voltages
should be may be more challenging. But if what are obviously DC outputs
vary significantly as you attempt to run the various functions of the
VCR, the power supply will be suspect.

See the various FAQs on these topics.

--- 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 is ignored.
To contact me, please use the feedback form on the S.E.R FAQ Web sites.