My JVC HR-DD 858 VCR has the following problem. It shuts down the power
(stand by) just a few seconds after switching it on. When i put in a
tape, the power comes on, it lays the tape in correctly and then spits
it out again.

I payed the investigation price for the repairshop. Their conclusion is
that the drum unit needs to be replaced at a price for which I can buy
three new VCR's.
I have the strong feeling that this is their standard answer, in case
they can't find the problem. Anyone an idea what could cause the
problem, or if their conclusion could be right?

tia.
Fem Verbeek

"Femme Verbeek" FV2003 ( at ) cyberjet ( dot ) nl wrote in message
...
| My JVC HR-DD 858 VCR has the following problem. It shuts down the power
| (stand by) just a few seconds after switching it on. When i put in a
| tape, the power comes on, it lays the tape in correctly and then spits
| it out again.
|
| I payed the investigation price for the repairshop. Their conclusion is
| that the drum unit needs to be replaced at a price for which I can buy
| three new VCR's.
| I have the strong feeling that this is their standard answer, in case
| they can't find the problem. Anyone an idea what could cause the
| problem, or if their conclusion could be right?

Is it the moisture sensor causing this?

N

"NSM" schreef in bericht
news:JwEad.4180$z96.2060@clgrps12...

"Femme Verbeek" FV2003 ( at ) cyberjet ( dot ) nl wrote in message
...
| My JVC HR-DD 858 VCR has the following problem. It shuts down the
power
| (stand by) just a few seconds after switching it on. When i put in a
| tape, the power comes on, it lays the tape in correctly and then
spits
| it out again.
|
| I payed the investigation price for the repairshop. Their conclusion
is
| that the drum unit needs to be replaced at a price for which I can
buy
| three new VCR's.
| I have the strong feeling that this is their standard answer, in
case
| they can't find the problem. Anyone an idea what could cause the
| problem, or if their conclusion could be right?

Is it the moisture sensor causing this?

Is there any? If so shouldn't that give an error message? My house is
very dry. It just shuts down normally.

--
Fem

"Femme Verbeek" FV2003 ( at ) cyberjet ( dot ) nl wrote in message
...
|
| "NSM" schreef in bericht
| news:JwEad.4180$z96.2060@clgrps12...

| Is it the moisture sensor causing this?
|
| Is there any? If so shouldn't that give an error message? My house is
| very dry. It just shuts down normally.

The VCRs I am used to have this. If it malfunctions it might cause this.
It's supposed to eject the tape until the moisture condition is removed,
since running will cause damage. A very cold tape in a warm room may result
in condensation problems.

N

"Femme Verbeek" FV2003 ( at ) cyberjet ( dot ) nl writes:

My JVC HR-DD 858 VCR has the following problem. It shuts down the power
(stand by) just a few seconds after switching it on. When i put in a
tape, the power comes on, it lays the tape in correctly and then spits
it out again.

I payed the investigation price for the repairshop. Their conclusion is
that the drum unit needs to be replaced at a price for which I can buy
three new VCR's.
I have the strong feeling that this is their standard answer, in case
they can't find the problem. Anyone an idea what could cause the
problem, or if their conclusion could be right?

It could be many things, only very rarely the "drum unit".

See the VCR Repair Guide at the site below. "Play and Record Mechanical
Problems":

http://repairfaq.ece.drexel.edu/sam/vcrfaq.htm#vcrprm

--- 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.

"Sam Goldwasser" wrote in message
...

| Is the moisture sensor not meant for a camera? This is just a normal
| home vcr for playing vhs tapes.
|
| Forget the sensor. Unless you just brought the VCR in from freezing
| cold, it's something else. It wouldn't shut down but say "DEW" in the
| display.

Many VCRs have no display now and no 'Dew' light, so shutdown is the only
option. And clearly this unit has a fault.

N

"NSM" writes:

"Sam Goldwasser" wrote in message
...

| Is the moisture sensor not meant for a camera? This is just a normal
| home vcr for playing vhs tapes.
|
| Forget the sensor. Unless you just brought the VCR in from freezing
| cold, it's something else. It wouldn't shut down but say "DEW" in the
| display.

Many VCRs have no display now and no 'Dew' light, so shutdown is the only
option. And clearly this unit has a fault.

Yes, but why is everyone jumping on the sensor bandwagon?

--- 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.

"Sam Goldwasser" wrote in message
...

| Many VCRs have no display now and no 'Dew' light, so shutdown is the
only
| option. And clearly this unit has a fault.

He is looking for suggestions. This is one. You may have others.

N

The problem with your JVC vcr has nothing to do with the drum unit,
accepting the tape and shutting down is about 95% mode switch problems, or
voltage regulator STK etc.......... clean the mode switch, or have someone
clean it for you.
"Femme Verbeek" FV2003 ( at ) cyberjet ( dot ) nl wrote in message
...
My JVC HR-DD 858 VCR has the following problem. It shuts down the power
(stand by) just a few seconds after switching it on. When i put in a
tape, the power comes on, it lays the tape in correctly and then spits
it out again.

I payed the investigation price for the repairshop. Their conclusion is
that the drum unit needs to be replaced at a price for which I can buy
three new VCR's.
I have the strong feeling that this is their standard answer, in case
they can't find the problem. Anyone an idea what could cause the
problem, or if their conclusion could be right?

tia.
Fem Verbeek

"Sam Goldwasser" wrote in message
...
"Femme Verbeek" FV2003 ( at ) cyberjet ( dot ) nl writes:

My JVC HR-DD 858 VCR has the following problem. It shuts down the power
(stand by) just a few seconds after switching it on. When i put in a
tape, the power comes on, it lays the tape in correctly and then spits
it out again.

I payed the investigation price for the repairshop. Their conclusion is
that the drum unit needs to be replaced at a price for which I can buy
three new VCR's.
I have the strong feeling that this is their standard answer, in case
they can't find the problem. Anyone an idea what could cause the
problem, or if their conclusion could be right?

It could be many things, only very rarely the "drum unit".

See the VCR Repair Guide at the site below. "Play and Record Mechanical
Problems":

http://repairfaq.ece.drexel.edu/sam/vcrfaq.htm#vcrprm

SNIP Links to Sam's very good web site

Hi,

The short answer is that the repair shop's conclusion may be correct.

The longer answer is that the HR-DD858 is a Hi-FI VCR with "Dynamic Drum".
Simply this feature tilts the angle of the whole drum assembly (Read: Upper
and lower drum, including drum motor) so you can cue and review a tape
without the noise bars that are typical with units that do not have this
feature. It also has a audio delay circuit so you can listen to the sound at
normal speed while performing cue at x7 speed!

If the capstan motor, drum motor or the Dynamic Drum do not initialise
(Read: Send capstan FG, Drum PG or DD Tilt signals back to the
microcontroller) when the unit is brought out of stand-by then you will get
the problem you mention.

So, as Sam say's it's possible for the drum to cause this problem, but there
are many other possible causes. You need to speak with the repair shop and
ask them to explain to you what's wrong with the drum unit that it needs
replacement. If you're satisfied with their answer then they are probably
correct.

However if it sound like bull**** and smells like bull****, chances are it's
bull****.

Perhaps the unit is in timer mode? Are there and strange lights lit on the
front of the unit that were not lit before?

Hope this helps!
James

Hi,

The short answer is that the repair shop's conclusion may be correct.

The longer answer is that the HR-DD858 is a Hi-FI VCR with "Dynamic
Drum".
Simply this feature tilts the angle of the whole drum assembly (Read:
Upper
and lower drum, including drum motor) so you can cue and review a tape
without the noise bars that are typical with units that do not have
this
feature. It also has a audio delay circuit so you can listen to the
sound at
normal speed while performing cue at x7 speed!


Very correct.

If the capstan motor, drum motor or the Dynamic Drum do not initialise
(Read: Send capstan FG, Drum PG or DD Tilt signals back to the
microcontroller) when the unit is brought out of stand-by then you
will get
the problem you mention.


The drum starts to rotate. I did not see any other movements.
Could it be that one of the motors is mechanically blocked. So helping
it at startup could unblock it?


So, as Sam say's it's possible for the drum to cause this problem, but
there
are many other possible causes. You need to speak with the repair shop
and
ask them to explain to you what's wrong with the drum unit that it
needs
replacement. If you're satisfied with their answer then they are
probably
correct.

I still have to pick up the vcr at the shop to have a better look.
It is a very large electronics shop, selling many brands, having their
own repair shop.
Chances are that the man at the desk can not answer any questions about
the investigation.

However if it sound like bull**** and smells like bull****, chances
are it's
bull****.

Perhaps the unit is in timer mode? Are there and strange lights lit on
the
front of the unit that were not lit before?

I would have noticed that.

Hope this helps!

Certainly. You confirmed clearly that the repair shop could be right.
There is another JVC specialised repairshop here in the area. But that
would take another investigation fee.


thank a lot

--
Fem

"awknod" schreef in bericht
...
The problem with your JVC vcr has nothing to do with the drum unit,
accepting the tape and shutting down is about 95% mode switch
problems, or
voltage regulator STK etc.......... clean the mode switch, or have
someone
clean it for you.

I tried to measure the voltage supply, see if it is weak. But it is hard
to disassemble the thing and find a good measuring point on the board. I
measured it over a resistor that becomes fairly hot. During tape inlay
the voltage went up a few volts from (what was it again) 6 to 8 V.
Nothing unexpected I think.


thanks

--
Fem

"Femme Verbeek" FV2003 ( at ) cyberjet ( dot ) nl writes:

I still have to pick up the vcr at the shop to have a better look.
It is a very large electronics shop, selling many brands, having their
own repair shop.
Chances are that the man at the desk can not answer any questions about
the investigation.

Note that if they are really in the business of *selling* new equipment,
they aren't going to be much interested in repair.

--- 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.

Hi For what its worth we here in the UK have had many problems with the
DD drum system.
They all have problems with the small black plastic gears inside the tilting
mech. Basically the plastic splits from the metal shaft to the outside,
possibly due to being too tight on the shaft!
Basically the mech when initialising runs fwd then back whilst reading the
opto pulses. If the count isn't correct/fast enough an error is assumed and
the VCR will go into standby mode. The gears seem to split easier when the
machine is used in hot and/or smoky environments.

As to diagnose this, you will usually hear ticking noises from the DDrum
when first powering up. If the gears are ok then it will sound smooth and
you need to look elsewhere.

I have had NO problems with mode switches on these units!

For whatever reason JVC do not supply new gears, and only a new drum is the
answer. As you say, it costs a fortune.
Having tried a few times to swap bits around to make a good unit, I can tell
you its dammed tricky to setup all 4 adjustment points so that it will track
the tape properly.

I think there may be a work around by disabling the gears, at least the unit
would initialise, but auto tracking and still/slo-mo might be adversely
affected.

Anyone else any experience on these DD mechs?

AW

"JVC dude" schreef in bericht
...
Hi For what its worth we here in the UK have had many problems with
the
DD drum system.
They all have problems with the small black plastic gears inside the
tilting
mech. Basically the plastic splits from the metal shaft to the
outside,
possibly due to being too tight on the shaft!
Basically the mech when initialising runs fwd then back whilst reading
the
opto pulses. If the count isn't correct/fast enough an error is
assumed and
the VCR will go into standby mode. The gears seem to split easier when
the
machine is used in hot and/or smoky environments.

As to diagnose this, you will usually hear ticking noises from the
DDrum
when first powering up. If the gears are ok then it will sound smooth
and
you need to look elsewhere.


I did not hear any ticking. So far the VCR worked always without error.
Just 1/2 a year after the end of 4 years warranty it breaks down.

I have had NO problems with mode switches on these units!

For whatever reason JVC do not supply new gears, and only a new drum
is the
answer. As you say, it costs a fortune.
Having tried a few times to swap bits around to make a good unit, I
can tell
you its dammed tricky to setup all 4 adjustment points so that it will
track
the tape properly.

I think there may be a work around by disabling the gears, at least
the unit
would initialise, but auto tracking and still/slo-mo might be
adversely
affected.

Anyone else any experience on these DD mechs?


Thanks to all for the answers.
I learned that this vcr has a tilting mechanism for the heads in order
to avoid striping, but is also weak in construction.
I'll try a closer inspection on this mechanism, but chances are that it
is beyond repair. Your answers convinced me that the repair shop could
be right.

regards
Fem Verbeek