Samsung DLP tv HLM617W color wheel

[[email protected]]

Doesn't the color wheel get sync'd up with the scan?
If so any failure in the sync would affect the motor on the color
wheel, wouldn't it?

 

[Guest]

Hi. Got a Samsung HLM617W dlp set here. Runs good for 10 minutes or so, then
picture begins breaking up, with a corresponding uneven sound from color
wheel motor housing. I reckon color wheel motor is the problem, but figured
to see if any of you guys have had similar issues with this model before.
Samsung parts place says they sell many of the color wheels. Sound right?
Just trying to be sure before I order parts, and it is possible it could be
mirror chip. All fans are good and running. Bulb is strong and not
flickering. It affects all parts of picture, including menu.

Danny

 

[[email protected]]

I don't mean the scan, but the sync pulses from the control sending the
different color information to the dlp.

I was thinking the scan as it relates to scanning between red, green,
and blue.

FYI color wheel motors do commonly have problems, but I have seen
control problems exhibit similar issues.

 

[Sam Goldwasser]

I don't mean the scan, but the sync pulses from the control sending the
different color information to the dlp.

I was thinking the scan as it relates to scanning between red, green,
and blue.

FYI color wheel motors do commonly have problems, but I have seen
control problems exhibit similar issues.

The color wheel and DLP/DMD chip are slaves to the incoming sync. So, yes,
could be the motor but could also be a video/sync issue. It's not likely
the DMD chip itself.

If you can locate the sync pulses driving the color wheel servo, start
there. If the motor isn't expensive, then, sure, try a replacement or
swap one in from another unit.

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[Art]

Normally, if you hear the Colour Wheel screaming, sounding like a small buzz
saw at times, then it is time to replace it. Rarely the DMD assembly will
cause problems if signals to the Colour Wheel become distorted. Excessive
dirt within the sets, dust buildup around the fans and ingressing into the
housing of the colour wheel also will contribute to the problems. Normally
you will hear the Colour Wheel spin up when the set is powered up, then most
of the mechanical noises are produced by the cooling fans.

 

[Art]

Disabling the Colour wheel and/or taking it out of the light path will
probably ender the flippin thing inoperable.

 

[Guest]

What I was going to try and do is this -- get the color wheel out of the way
of the light path and see if set runs stable as a black and white. I know
the high speed of this wheel, near 11000 rpm, will require great care in
this plan. Samsung gets like 130 for the wheel motor. Lady has had no end of
trouble with set and Samsung will no longer warranty it, therefore I have it
to look into. Other than 2 bulbs and a new ballast I don't know what else
has been done to it. She wants a firm estimate of repairs, so she can decide
then. In other words, I must be dead on before I spends her money. Perhaps
set will run with color wheel unpluged and out of the way. I should then be
able to tell if it is a sync or mechanical problem with color wheel moved,
at any rate.

Danny

 

[James Sweet]

What I was going to try and do is this -- get the color wheel out of the way
of the light path and see if set runs stable as a black and white. I know
the high speed of this wheel, near 11000 rpm, will require great care in
this plan. Samsung gets like 130 for the wheel motor. Lady has had no end of
trouble with set and Samsung will no longer warranty it, therefore I have it
to look into. Other than 2 bulbs and a new ballast I don't know what else
has been done to it. She wants a firm estimate of repairs, so she can decide
then. In other words, I must be dead on before I spends her money. Perhaps
set will run with color wheel unpluged and out of the way. I should then be
able to tell if it is a sync or mechanical problem with color wheel moved,
at any rate.

Danny

No need to take it out of the way, just unplug it, the screen will be all
one color but otherwise no different than it removed entirely. The unit may
wait until the wheel is spun up before doing anything though.

 

[Art]

Control circuitry senses the rotation of the Colour Wheel before allowing
lamp igniton in these devices. Disabeling the Colour Wheel or it's
interconection with the DMD and control circuitry probably will result in
not allowing any light, theferore display to be produced. Diagnostics
normally confirm rotation of the colour wheel, hearing it spin up or
visually confirming that fact if there is a failure to ignite the lamp in
these sets.

 

[Guest]

Yeah, I found that out today. Demounted wheel and bolted to frame to keep it
from wandering about. It is distinctly noisy when it spins up. You are
right, lamp won't come on with color wheel removed, even with cables
connected. Guess I should remount properly and make sure nothing else has
gone awry. These DLP sets are new to me so I am learning their ins and outs.

Danny

 

[Guest]

Disregard my last post. I had forgotten to plug ballast power back in. Light
works better with electricity attached.

Latest DLP experiments and results --

Samsung DLP set will run fine with color wheel mounted outside of light
tunnel, and shows in black and white, but will not run if color wheel motor
is unplugged.

After this test, set runs and picture very jittery as before. Took color
wheel out of motor mount. I then see a small infrared sensor, like used in
vcrs. It had some dust on it. I cleaned away the dust, and gently dusted the
wheel, but it looked clean anyway. I remounted wheel to frame and
restarted --

At this point picture is perfect, in black and white. I allowed to run some
hours while I did other work and errands. Stable as can be. I will remount
in light tunnel tomorrow and allow to run the day. If solid, will reassemble
and see how she does.

Cheers, Danny