I have a Panasonic SC-HT900 "home theatre in a box", about 2.5 years
old, that's developed a problem over the past couple of weeks.

I'll describe the problem and my troubleshooting efforts in a moment,
but I'm pretty sure it's a weak DVD laser. Since the pickup lists for
around $80US on the Panasonic parts site and this is a
theater-in-a-box that I've generally been happy with, it seems worth
repairing.

My questions a

1. Can someone with access to a service manual (or who's replaced the
pickup on this or a similar unit) tell me what's involved? Does
this require major realignment or just some ugly disassembly, gear
swapping, and a three-screw jitter adjustment at the end of it
all?

2. I'm located in Vancouver, Canada. Panasonic lists a few
independent service shops up here. Does anyone have any
experience with any of these guys?

3. If I decide to repair it myself, what's the best way to get
Panasonic parts up here? Is it best to order through Panasonic's
"www.pasc.panasonic.com" site? Will they ship here?

4. What's the best way to get a service manual for this unit?

Thanks very much in advance...

Anyway, onto the problem description:

When cold, the unit will play DVDs fine. After warming up for 30
minutes or so, I'll notice the playback freezing for a second or two
every once in a while. This isn't happening at a layer transition,
and it isn't always at the same point on any given DVD. It also
happens with different DVDs. At first, this happened once or twice,
and then the player was fine for another hour. Now, it usually starts
freezing every minute or so five or six times in a row before giving
up and ejecting the disk with a "DVD H05" error. After this,
sometimes the DVD can be immediately reinserted; sometimes it won't
recognize the DVD until the unit's cooled down again.

I tried cleaning the lens a couple of times (though I haven't tried to
reach the turning mirror), but the freeze problem persists. Anyway,
it certainly seems to be heat-related. It happens once the player has
warmed up, and running the machine without the cover reduces or
eliminates the problem, at least for now.

In an attempt to check for a marginal spindle motor (since I know some
Panasonic units have this problem), I tried applying light pressure to
the top "spindle clamp" while it was rotating to put a little stress
on the motor. This didn't have any effect on playback.

After much Googling, I was able to cobble together some information on
accessing some of the service mode displays. I ran the unit for a
while in its jitter check mode (with unit stopped, press "Tune
Mode/Stop" on main unit and "5" on remote) until it started failing.
The normal jitter with this particular DVD was around 10%, but at one
point I saw it rise to 15% when the unit warmed up. When I removed
the cover, the jitter dropped back down to 11% or so. However, with
the cover back on when the playback started freezing, the jitter was
still down at 10-11%, so I don't think jitter is a problem per se.
The error counter got bumped for each freeze, but at one point, though
there wasn't anything obviously wrong with the playback, the error
counter started counting up once a second or so until I paused and
restarted the playback.

The clincher was when I checked the laser current. I used the
following procedu with the player cold, turn on power to get "NO
DISC" display, press "Tune Mode/Stop" on unit and then "Display" on
remote. The display read:

LDD034 082

which I understand to mean the initial factory DVD laser current was
34mA and it's now 82mA. (WAH!) After I let the player warm up, the
laser current had risen to 90mA.

I also accessed the error log (with "Tune Mode/Stop" on unit and "0"
on remote). It showed a long list of "F0BF" and "H05" errors from my
testing, which are apparently "physical layer not recognizable" and
"seek error" respectively.

Anyway, I assume this has to just be a bad pickup problem, right?

Again, thanks in advance for any help.

--
Kevin Buhr

"Kevin Buhr" wrote in message
...
I have a Panasonic SC-HT900 "home theatre in a box", about 2.5 years
old, that's developed a problem over the past couple of weeks.

I'll describe the problem and my troubleshooting efforts in a moment,
but I'm pretty sure it's a weak DVD laser. Since the pickup lists for
around $80US on the Panasonic parts site and this is a
theater-in-a-box that I've generally been happy with, it seems worth
repairing.

My questions a

1. Can someone with access to a service manual (or who's replaced the
pickup on this or a similar unit) tell me what's involved? Does
this require major realignment or just some ugly disassembly, gear
swapping, and a three-screw jitter adjustment at the end of it
all?

2. I'm located in Vancouver, Canada. Panasonic lists a few
independent service shops up here. Does anyone have any
experience with any of these guys?

3. If I decide to repair it myself, what's the best way to get
Panasonic parts up here? Is it best to order through Panasonic's
"www.pasc.panasonic.com" site? Will they ship here?

4. What's the best way to get a service manual for this unit?

Thanks very much in advance...

Anyway, onto the problem description:

When cold, the unit will play DVDs fine. After warming up for 30
minutes or so, I'll notice the playback freezing for a second or two
every once in a while. This isn't happening at a layer transition,
and it isn't always at the same point on any given DVD. It also
happens with different DVDs. At first, this happened once or twice,
and then the player was fine for another hour. Now, it usually starts
freezing every minute or so five or six times in a row before giving
up and ejecting the disk with a "DVD H05" error. After this,
sometimes the DVD can be immediately reinserted; sometimes it won't
recognize the DVD until the unit's cooled down again.

I tried cleaning the lens a couple of times (though I haven't tried to
reach the turning mirror), but the freeze problem persists. Anyway,
it certainly seems to be heat-related. It happens once the player has
warmed up, and running the machine without the cover reduces or
eliminates the problem, at least for now.

In an attempt to check for a marginal spindle motor (since I know some
Panasonic units have this problem), I tried applying light pressure to
the top "spindle clamp" while it was rotating to put a little stress
on the motor. This didn't have any effect on playback.

After much Googling, I was able to cobble together some information on
accessing some of the service mode displays. I ran the unit for a
while in its jitter check mode (with unit stopped, press "Tune
Mode/Stop" on main unit and "5" on remote) until it started failing.
The normal jitter with this particular DVD was around 10%, but at one
point I saw it rise to 15% when the unit warmed up. When I removed
the cover, the jitter dropped back down to 11% or so. However, with
the cover back on when the playback started freezing, the jitter was
still down at 10-11%, so I don't think jitter is a problem per se.
The error counter got bumped for each freeze, but at one point, though
there wasn't anything obviously wrong with the playback, the error
counter started counting up once a second or so until I paused and
restarted the playback.

The clincher was when I checked the laser current. I used the
following procedu with the player cold, turn on power to get "NO
DISC" display, press "Tune Mode/Stop" on unit and then "Display" on
remote. The display read:

LDD034 082

which I understand to mean the initial factory DVD laser current was
34mA and it's now 82mA. (WAH!) After I let the player warm up, the
laser current had risen to 90mA.

I also accessed the error log (with "Tune Mode/Stop" on unit and "0"
on remote). It showed a long list of "F0BF" and "H05" errors from my
testing, which are apparently "physical layer not recognizable" and
"seek error" respectively.

Anyway, I assume this has to just be a bad pickup problem, right?

Again, thanks in advance for any help.

--
Kevin Buhr

You've done all of the right things to prove a bad pickup. Replacement is as
you say, just a case of swapping it, and checking / adjusting the jitter
factor - as you say, three tilt screws. Don't forget the shorting points on
the new laser.

In normal operation, with a good pickup, you should be able to obtain a
jitter figure well below 10% - often as low as 7% - measured around the
centre of the outer layer, say 20 minutes into the disc, and using a full
quality full priced pressed disc, that is, not a newspaper freebie. You
should be able to leave the player running from cold, from the start of the
disc, and not see the jitter figure rise more than 1.5%. A steadily
increasing jitter figure as play progresses, and the player warms up, is
usually a good sign of a bad laser.

Arfa

Be very careful about static whilst fitting it !! DVD lasers are easily
killed by off, even though there is a shorting link which you only remove
after its wiring is connected !!

AW

"Arfa Daily" wrote in message
...

"Kevin Buhr" wrote in message
...
I have a Panasonic SC-HT900 "home theatre in a box", about 2.5 years
old, that's developed a problem over the past couple of weeks.

I'll describe the problem and my troubleshooting efforts in a moment,
but I'm pretty sure it's a weak DVD laser. Since the pickup lists for
around $80US on the Panasonic parts site and this is a
theater-in-a-box that I've generally been happy with, it seems worth
repairing.

My questions a

1. Can someone with access to a service manual (or who's replaced the
pickup on this or a similar unit) tell me what's involved? Does
this require major realignment or just some ugly disassembly, gear
swapping, and a three-screw jitter adjustment at the end of it
all?

2. I'm located in Vancouver, Canada. Panasonic lists a few
independent service shops up here. Does anyone have any
experience with any of these guys?

3. If I decide to repair it myself, what's the best way to get
Panasonic parts up here? Is it best to order through Panasonic's
"www.pasc.panasonic.com" site? Will they ship here?

4. What's the best way to get a service manual for this unit?

Thanks very much in advance...

Anyway, onto the problem description:

When cold, the unit will play DVDs fine. After warming up for 30
minutes or so, I'll notice the playback freezing for a second or two
every once in a while. This isn't happening at a layer transition,
and it isn't always at the same point on any given DVD. It also
happens with different DVDs. At first, this happened once or twice,
and then the player was fine for another hour. Now, it usually starts
freezing every minute or so five or six times in a row before giving
up and ejecting the disk with a "DVD H05" error. After this,
sometimes the DVD can be immediately reinserted; sometimes it won't
recognize the DVD until the unit's cooled down again.

I tried cleaning the lens a couple of times (though I haven't tried to
reach the turning mirror), but the freeze problem persists. Anyway,
it certainly seems to be heat-related. It happens once the player has
warmed up, and running the machine without the cover reduces or
eliminates the problem, at least for now.

In an attempt to check for a marginal spindle motor (since I know some
Panasonic units have this problem), I tried applying light pressure to
the top "spindle clamp" while it was rotating to put a little stress
on the motor. This didn't have any effect on playback.

After much Googling, I was able to cobble together some information on
accessing some of the service mode displays. I ran the unit for a
while in its jitter check mode (with unit stopped, press "Tune
Mode/Stop" on main unit and "5" on remote) until it started failing.
The normal jitter with this particular DVD was around 10%, but at one
point I saw it rise to 15% when the unit warmed up. When I removed
the cover, the jitter dropped back down to 11% or so. However, with
the cover back on when the playback started freezing, the jitter was
still down at 10-11%, so I don't think jitter is a problem per se.
The error counter got bumped for each freeze, but at one point, though
there wasn't anything obviously wrong with the playback, the error
counter started counting up once a second or so until I paused and
restarted the playback.

The clincher was when I checked the laser current. I used the
following procedu with the player cold, turn on power to get "NO
DISC" display, press "Tune Mode/Stop" on unit and then "Display" on
remote. The display read:

LDD034 082

which I understand to mean the initial factory DVD laser current was
34mA and it's now 82mA. (WAH!) After I let the player warm up, the
laser current had risen to 90mA.

I also accessed the error log (with "Tune Mode/Stop" on unit and "0"
on remote). It showed a long list of "F0BF" and "H05" errors from my
testing, which are apparently "physical layer not recognizable" and
"seek error" respectively.

Anyway, I assume this has to just be a bad pickup problem, right?

Again, thanks in advance for any help.

--
Kevin Buhr

You've done all of the right things to prove a bad pickup. Replacement is
as
you say, just a case of swapping it, and checking / adjusting the jitter
factor - as you say, three tilt screws. Don't forget the shorting points
on
the new laser.

In normal operation, with a good pickup, you should be able to obtain a
jitter figure well below 10% - often as low as 7% - measured around the
centre of the outer layer, say 20 minutes into the disc, and using a full
quality full priced pressed disc, that is, not a newspaper freebie. You
should be able to leave the player running from cold, from the start of
the
disc, and not see the jitter figure rise more than 1.5%. A steadily
increasing jitter figure as play progresses, and the player warms up, is
usually a good sign of a bad laser.

Arfa