Hitachi Projection TV - CRT Contamination

J

Joe R.

Guest
I have a Hitachi Projection TV, Model 50ux7k, that has contamination
inside the Green CRT. It show up on the screen as a red line from the
top to the center of the screen. Also, the red and blue CRT's have a
small amount that shows up as a blue dot (1/8") and a yellow mark
(3/8") near the center of the screen. You can see a black residue
inside the crt's when the top lens is removed. I know that the lens
can be opened and this can probabaly be cleaned out. My question is:
has anyone had the same issue and successfully cleaned it out? If so,
what type of oil do I refilled with? Is there a proper procedure to
follow when re-filling? Any help would be greatly appreaciated.

Thank you!

Joe R.
 
"Joe R." <jir@fngp.com> wrote in message
news:efd51c51.0401082041.79a15c5d@posting.google.com...
I have a Hitachi Projection TV, Model 50ux7k, that has contamination
inside the Green CRT. It show up on the screen as a red line from the
top to the center of the screen. Also, the red and blue CRT's have a
small amount that shows up as a blue dot (1/8") and a yellow mark
(3/8") near the center of the screen. You can see a black residue
inside the crt's when the top lens is removed. I know that the lens
can be opened and this can probabaly be cleaned out. My question is:
has anyone had the same issue and successfully cleaned it out? If so,
what type of oil do I refilled with? Is there a proper procedure to
follow when re-filling? Any help would be greatly appreaciated.

Thank you!

Joe R.
Click to expand...
That sounds a lot like phosphor burn which you can't fix without replacing
the tubes. It's hard to say without looking though, it could indeed be
contamination. You should refill it with projection TV coolant, you can buy
it from MCM.
 
James,
I will try to wipe it clean and refill before trying replacing the
tube. Is there any procedure to follow to drain and refill? What
about wiping/cleaning the contamination, any precautions?
Thanks!

Joe R.


"James Sweet" <jamessweet@hotmail.com> wrote in message news:<bUrLb.4516$xy6.16397@attbi_s02>...
"Joe R." <jir@fngp.com> wrote in message
news:efd51c51.0401082041.79a15c5d@posting.google.com...
I have a Hitachi Projection TV, Model 50ux7k, that has contamination
inside the Green CRT. It show up on the screen as a red line from the
top to the center of the screen. Also, the red and blue CRT's have a
small amount that shows up as a blue dot (1/8") and a yellow mark
(3/8") near the center of the screen. You can see a black residue
inside the crt's when the top lens is removed. I know that the lens
can be opened and this can probabaly be cleaned out. My question is:
has anyone had the same issue and successfully cleaned it out? If so,
what type of oil do I refilled with? Is there a proper procedure to
follow when re-filling? Any help would be greatly appreaciated.

Thank you!

Joe R.

That sounds a lot like phosphor burn which you can't fix without replacing
the tubes. It's hard to say without looking though, it could indeed be
contamination. You should refill it with projection TV coolant, you can buy
it from MCM.
Click to expand...
 
That is a phosphor burn on the face of the tubes. A common fault on that
model due to a certain type of failure . You are correct in saying it needs
all three picture tubes replaced to correct the problem. Around a $1000 job
as the tubes are around $300 each.

David

"James Sweet" <jamessweet@hotmail.com> wrote in message
news:bUrLb.4516$xy6.16397@attbi_s02...
"Joe R." <jir@fngp.com> wrote in message
news:efd51c51.0401082041.79a15c5d@posting.google.com...
I have a Hitachi Projection TV, Model 50ux7k, that has contamination
inside the Green CRT. It show up on the screen as a red line from the
top to the center of the screen. Also, the red and blue CRT's have a
small amount that shows up as a blue dot (1/8") and a yellow mark
(3/8") near the center of the screen. You can see a black residue
inside the crt's when the top lens is removed. I know that the lens
can be opened and this can probabaly be cleaned out. My question is:
has anyone had the same issue and successfully cleaned it out? If so,
what type of oil do I refilled with? Is there a proper procedure to
follow when re-filling? Any help would be greatly appreaciated.

Thank you!

Joe R.

That sounds a lot like phosphor burn which you can't fix without replacing
the tubes. It's hard to say without looking though, it could indeed be
contamination. You should refill it with projection TV coolant, you can
buy
it from MCM.
Click to expand...
 
Joe,

If these marks resemble Red, Green or Blue crayon marks on the screen,
then it's a certainty that you have etched CRTS. There is no fix aside
from replacing the burned tubes. I would recommend against this based
on the age of the set. Simply not worth it. There is also the matter
of what caused this. Normally it is caused by loss of deflection but
this can be from a number of other sources. If the set lost drive
voltage and was allowed to go into OC shutdown (screen got too bright)
would be my first guess..

To replace the glycol is a VERY involved job. To do it correctly ,the
tubes must be completely removed from the set and disassembled. If you
are a novice this is not the job for you. If you attempt to drain the
tubes in place all you will get is a nasty mess and a junk TV. IF the
tubes are etched then replacing the glycol is an exercise in futility.

FYI -None of the rubber gaskets or diaphragms are available for
Hitachi projection sets. If they where to be damaged in the job you
would be SOL.

I know etched CRTs can be distracting, but there really is no easy
fix.

Regards

Jim

On 8 Jan 2004 20:41:54 -0800, jir@fngp.com (Joe R.) wrote:

I have a Hitachi Projection TV, Model 50ux7k, that has contamination
inside the Green CRT. It show up on the screen as a red line from the
top to the center of the screen. Also, the red and blue CRT's have a
small amount that shows up as a blue dot (1/8") and a yellow mark
(3/8") near the center of the screen. You can see a black residue
inside the crt's when the top lens is removed. I know that the lens
can be opened and this can probabaly be cleaned out. My question is:
has anyone had the same issue and successfully cleaned it out? If so,
what type of oil do I refilled with? Is there a proper procedure to
follow when re-filling? Any help would be greatly appreaciated.

Thank you!

Joe R.
Click to expand...
 
Giluxis <dude@dude.com> wrote in message news:<m1k00056i19ndin4t39f5he56e915g64tl@4ax.com>...
Joe,

If these marks resemble Red, Green or Blue crayon marks on the screen,
then it's a certainty that you have etched CRTS. There is no fix aside
from replacing the burned tubes. I would recommend against this based
on the age of the set. Simply not worth it. There is also the matter
of what caused this. Normally it is caused by loss of deflection but
this can be from a number of other sources. If the set lost drive
voltage and was allowed to go into OC shutdown (screen got too bright)
would be my first guess..

To replace the glycol is a VERY involved job. To do it correctly ,the
tubes must be completely removed from the set and disassembled. If you
are a novice this is not the job for you. If you attempt to drain the
tubes in place all you will get is a nasty mess and a junk TV. IF the
tubes are etched then replacing the glycol is an exercise in futility.

FYI -None of the rubber gaskets or diaphragms are available for
Hitachi projection sets. If they where to be damaged in the job you
would be SOL.

I know etched CRTs can be distracting, but there really is no easy
fix.

Regards

Jim

On 8 Jan 2004 20:41:54 -0800, jir@fngp.com (Joe R.) wrote:

I have a Hitachi Projection TV, Model 50ux7k, that has contamination
inside the Green CRT. It show up on the screen as a red line from the
top to the center of the screen. Also, the red and blue CRT's have a
small amount that shows up as a blue dot (1/8") and a yellow mark
(3/8") near the center of the screen. You can see a black residue
inside the crt's when the top lens is removed. I know that the lens
can be opened and this can probabaly be cleaned out. My question is:
has anyone had the same issue and successfully cleaned it out? If so,
what type of oil do I refilled with? Is there a proper procedure to
follow when re-filling? Any help would be greatly appreaciated.

Thank you!

Joe R.
Click to expand...

Thanks everyone for all the information!

Everyone was correct. The tubes are burned (green has about a 1.5"
line from the center to outer edge and blue has one small round spot
in center). This set had a couple of cold solder joints on the
deflection board which more that likely caused the burns. After
repairing the solder joints, burned tubes were discovered. I was only
able to locate one source for new tubes at approx $360 each. I could
get away with only replacing the green and blue, but probably not
worth it at over $700 (plus shipping) just for parts. Anyone know of
any other sources for lower cost for Hitachi tubes? Any place
specializing in salvage assy's?

Thanks!

Joe R.
 
Thanks everyone for all the information!

Everyone was correct. The tubes are burned (green has about a 1.5"
line from the center to outer edge and blue has one small round spot
in center). This set had a couple of cold solder joints on the
deflection board which more that likely caused the burns. After
repairing the solder joints, burned tubes were discovered. I was only
able to locate one source for new tubes at approx $360 each. I could
get away with only replacing the green and blue, but probably not
worth it at over $700 (plus shipping) just for parts. Anyone know of
any other sources for lower cost for Hitachi tubes? Any place
specializing in salvage assy's?

Thanks!
Click to expand...

Doesn't it suck how a few cold solder joints can do so much damage? If you
post the model number of the set or the numbers off the tubes periodically
someone may be able to help you, depending on the condition and features of
the rest of the set, it may be worthwhile to put a set of new tubes in it,
the tubes are the only thing that really wears out and ages, if the set
doesn't have a history of toasting expensive or impossible to get parts, you
may want to consider a set of rebuilt tubes, yeah it's expensive, but it may
be a few hundred cheaper than a comparable new set, you'll have to use your
judgement there.
 
i heard that letting the TV run for hours on a snowy screen causes the burns
to be a lot less noticable, but on the contrary, its very hard on the CRTs.
nothing to loose, so give it a shot.









"James Sweet" <jamessweet@hotmail.com> wrote in message
news:QQYMb.42735$Rc4.167402@attbi_s54...
Thanks everyone for all the information!

Everyone was correct. The tubes are burned (green has about a 1.5"
line from the center to outer edge and blue has one small round spot
in center). This set had a couple of cold solder joints on the
deflection board which more that likely caused the burns. After
repairing the solder joints, burned tubes were discovered. I was only
able to locate one source for new tubes at approx $360 each. I could
get away with only replacing the green and blue, but probably not
worth it at over $700 (plus shipping) just for parts. Anyone know of
any other sources for lower cost for Hitachi tubes? Any place
specializing in salvage assy's?

Thanks!



Doesn't it suck how a few cold solder joints can do so much damage? If you
post the model number of the set or the numbers off the tubes periodically
someone may be able to help you, depending on the condition and features
of
the rest of the set, it may be worthwhile to put a set of new tubes in it,
the tubes are the only thing that really wears out and ages, if the set
doesn't have a history of toasting expensive or impossible to get parts,
you
may want to consider a set of rebuilt tubes, yeah it's expensive, but it
may
be a few hundred cheaper than a comparable new set, you'll have to use
your
judgement there.
Click to expand...
 
What are you smoking .


--
"Watch the return E-Mail addy its false"
"Mike" <temp@temp.com> wrote in message
news:4n_Mb.39456$RT.30613@fe2.columbus.rr.com...
i heard that letting the TV run for hours on a snowy screen causes the
burns
to be a lot less noticable, but on the contrary, its very hard on the
CRTs.
nothing to loose, so give it a shot.









"James Sweet" <jamessweet@hotmail.com> wrote in message
news:QQYMb.42735$Rc4.167402@attbi_s54...


Thanks everyone for all the information!

Everyone was correct. The tubes are burned (green has about a 1.5"
line from the center to outer edge and blue has one small round spot
in center). This set had a couple of cold solder joints on the
deflection board which more that likely caused the burns. After
repairing the solder joints, burned tubes were discovered. I was only
able to locate one source for new tubes at approx $360 each. I could
get away with only replacing the green and blue, but probably not
worth it at over $700 (plus shipping) just for parts. Anyone know of
any other sources for lower cost for Hitachi tubes? Any place
specializing in salvage assy's?

Thanks!



Doesn't it suck how a few cold solder joints can do so much damage? If
you
post the model number of the set or the numbers off the tubes
periodically
someone may be able to help you, depending on the condition and features
of
the rest of the set, it may be worthwhile to put a set of new tubes in
it,
the tubes are the only thing that really wears out and ages, if the set
doesn't have a history of toasting expensive or impossible to get parts,
you
may want to consider a set of rebuilt tubes, yeah it's expensive, but it
may
be a few hundred cheaper than a comparable new set, you'll have to use
your
judgement there.
Click to expand...
 
"Mike" <temp@temp.com> wrote in message
news:4n_Mb.39456$RT.30613@fe2.columbus.rr.com...
i heard that letting the TV run for hours on a snowy screen causes the
burns
to be a lot less noticable, but on the contrary, its very hard on the
CRTs.
nothing to loose, so give it a shot.
Click to expand...
If the burn is that severe then there's nothing you can do, a black mark on
the face of the CRT means there's zero phosphor left, the tubes are shot.
 
"James Sweet" <jamessweet@hotmail.com> wrote in message news:<QQYMb.42735$Rc4.167402@attbi_s54>...
Thanks everyone for all the information!

Everyone was correct. The tubes are burned (green has about a 1.5"
line from the center to outer edge and blue has one small round spot
in center). This set had a couple of cold solder joints on the
deflection board which more that likely caused the burns. After
repairing the solder joints, burned tubes were discovered. I was only
able to locate one source for new tubes at approx $360 each. I could
get away with only replacing the green and blue, but probably not
worth it at over $700 (plus shipping) just for parts. Anyone know of
any other sources for lower cost for Hitachi tubes? Any place
specializing in salvage assy's?

Thanks!
Click to expand...


Doesn't it suck how a few cold solder joints can do so much damage? If you
post the model number of the set or the numbers off the tubes periodically
someone may be able to help you, depending on the condition and features of
the rest of the set, it may be worthwhile to put a set of new tubes in it,
the tubes are the only thing that really wears out and ages, if the set
doesn't have a history of toasting expensive or impossible to get parts, you
may want to consider a set of rebuilt tubes, yeah it's expensive, but it may
be a few hundred cheaper than a comparable new set, you'll have to use your
judgement there.
Click to expand...


I've been checking around for projection tubes and have run into a
question that no one has been able to answer. The service manual for
Hitachi model # 50ux7k lists the following part numbers for each tube
assy:

Red - 4866381
green - 4866382
blue - 4866383

One source, Part solver.com, lists these three tubes for $353 each.
They also list these 3 additional part numbers:

red - 4869321
green - 4866385
blue - 4869323

The green is the only one that states it is a replacement for #
4866382 and is is $354.
The red and blue are $282 each and do not have any information about
them. I called Customer Service, but they could not tell me any
information about the difference.

Can anyone tell me what the difference is, or lead me to a source that
can clear up the confusion in these projection tube part numbers:

Red - 4866381 vs 4869321
green - 4866385 vs 4866385
blue - 4866383 vs 4869323

Another source also lists Part # 4866384 as a replacement for the
green projection tube.

Any information to clear up the difference in parts, will be very
helpful in my decision to repair or not to repair.

Thanks,
Joe R.
 
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