C
Colin McCormick
Guest
x-no-archive:yes
J
Jason D.
Guest
On Tue, 24 Feb 2004 01:53:48 GMT, "David W. McGaffney"
<kvm@neo.rr.com> wrote:
cracked board is also due to the to drop that also broke free shadow
mask internal to CRT. Shake the TV and see the bars wiggle.
Hope you didn't pay lot for that wrecked set, like 25 or so. These
27" sets is not that much, about 200 to 250 US.
Samsung is only one that doesn't sell CRTs. They want you to exchange
whole unit not just crt.
If was RCA or JVC, you can buy a new tube but that is madness because
you can get ANOTHER set with warrenty!
Cheers,
Wizard
<kvm@neo.rr.com> wrote:
Viewed your jpg of this, This is sure sign that CRT is wrecked. The
cracked board is also due to the to drop that also broke free shadow
mask internal to CRT. Shake the TV and see the bars wiggle.
Hope you didn't pay lot for that wrecked set, like 25 or so. These
27" sets is not that much, about 200 to 250 US.
Samsung is only one that doesn't sell CRTs. They want you to exchange
whole unit not just crt.
If was RCA or JVC, you can buy a new tube but that is madness because
you can get ANOTHER set with warrenty!
Cheers,
Wizard
D
David W. McGaffney
Guest
No... didn't pay much... It came with a bunch of other "repairable" sets...
It's a shame though.... Maybe I'll find one that has another problem...
Weird how the screen has "colorbars" though...
Usually you would see a "purity" problem in the corners of the tube...
Have you seen this on non-HDTV Samsungs or other mfrs??
Thanks... You saved me from spending more on it.
Well... I at least have a good chassis to work with
PS you CAN get the crt from Samsung for $296 but why would anyone want to???
Dave
"Jason D." <jpero@sympatico.ca> wrote in message
news:403ab6f2.9720386@news1.on.sympatico.ca...
It's a shame though.... Maybe I'll find one that has another problem...
Weird how the screen has "colorbars" though...
Usually you would see a "purity" problem in the corners of the tube...
Have you seen this on non-HDTV Samsungs or other mfrs??
Thanks... You saved me from spending more on it.
Well... I at least have a good chassis to work with
PS you CAN get the crt from Samsung for $296 but why would anyone want to???
Dave
"Jason D." <jpero@sympatico.ca> wrote in message
news:403ab6f2.9720386@news1.on.sympatico.ca...
On Tue, 24 Feb 2004 01:53:48 GMT, "David W. McGaffney"
kvm@neo.rr.com> wrote:
Hi guys....
Any thoughts/ideas are welcome
Thanks!
Dave Mc
Viewed your jpg of this, This is sure sign that CRT is wrecked. The
cracked board is also due to the to drop that also broke free shadow
mask internal to CRT. Shake the TV and see the bars wiggle.
Hope you didn't pay lot for that wrecked set, like 25 or so. These
27" sets is not that much, about 200 to 250 US.
Samsung is only one that doesn't sell CRTs. They want you to exchange
whole unit not just crt.
If was RCA or JVC, you can buy a new tube but that is madness because
you can get ANOTHER set with warrenty!
Cheers,
Wizard
J
Jason D.
Guest
On Tue, 24 Feb 2004 02:55:40 GMT, "David W. McGaffney"
<kvm@neo.rr.com> wrote:
but yours was the winner for "beauty looks" damage.
Samsung only want us to exchange sets if CRT is the issue or excessive
service under warrenty.
That's extreme pricing. RCA & JVC is slightly reasonable for CRT
prices.
How did you get those "newish" stuff through? I'd love to find few
newer chassis for pulling parts and maybe a CRT.
Cheers,
Wizard
<kvm@neo.rr.com> wrote:
I had seen one or two flat crt dropped set and all showed similar lookNo... didn't pay much... It came with a bunch of other "repairable" sets...
It's a shame though.... Maybe I'll find one that has another problem...
Weird how the screen has "colorbars" though...
Usually you would see a "purity" problem in the corners of the tube...
Have you seen this on non-HDTV Samsungs or other mfrs??
Thanks... You saved me from spending more on it.
Well... I at least have a good chassis to work with
but yours was the winner for "beauty looks" damage.
Thanks for letting me know. I thought it was the issue because
Samsung only want us to exchange sets if CRT is the issue or excessive
service under warrenty.
That's extreme pricing. RCA & JVC is slightly reasonable for CRT
prices.
How did you get those "newish" stuff through? I'd love to find few
newer chassis for pulling parts and maybe a CRT.
Cheers,
Wizard
T
The Al Bundy
Guest
"David W. McGaffney" <kvm@neo.rr.com> wrote
news:M2z_b.886$OE4.624@fe1.columbus.rr.com...
Shadow mask is like a thin sheet of metal as big as the screen. In this mask
are very tiny holes where the electron beam can go through. With a
Trinitron there are no holes but vertical metal stripes, holded in place by
2 horizontal thin wires (those you can see if you look closely!).
The colorbar is not weird if you know that the shadow mask is for
'selecting' the right electron beam to hit the right color of phosphor.
Otherwise it would be 'easy' to just use 1 electron beam for all 3 colors,
but then it is impossible to make sure that the gun hits exactly and only
the blue phosphor for all blue color data..
By using 3 guns for red/green/blue and a shadowmask it is sure that the
right color can be made.
When this shadowmask is gone or out of position any gun can reach any color
of phosphor and causing different colors on the screen.
The purity problem is caused by some magnetic field that just locally
misaligns the electron beams with the shadowmask and phosphor. Ever tried to
put a magnet next to the electron gun? Try it and you will see nice
colors.
But take care with magnets and a color CRT! You can easily pull the
shadowmask loose...
Al
news:M2z_b.886$OE4.624@fe1.columbus.rr.com...
Ok, you see colorbars but actually they are caused by a loose shadow mask.No... didn't pay much... It came with a bunch of other "repairable"
sets...
It's a shame though.... Maybe I'll find one that has another problem...
Weird how the screen has "colorbars" though...
Usually you would see a "purity" problem in the corners of the tube...
Have you seen this on non-HDTV Samsungs or other mfrs??
Thanks... You saved me from spending more on it.
Well... I at least have a good chassis to work with
PS you CAN get the crt from Samsung for $296 but why would anyone want
to???
Dave
Shadow mask is like a thin sheet of metal as big as the screen. In this mask
are very tiny holes where the electron beam can go through. With a
Trinitron there are no holes but vertical metal stripes, holded in place by
2 horizontal thin wires (those you can see if you look closely!).
The colorbar is not weird if you know that the shadow mask is for
'selecting' the right electron beam to hit the right color of phosphor.
Otherwise it would be 'easy' to just use 1 electron beam for all 3 colors,
but then it is impossible to make sure that the gun hits exactly and only
the blue phosphor for all blue color data..
By using 3 guns for red/green/blue and a shadowmask it is sure that the
right color can be made.
When this shadowmask is gone or out of position any gun can reach any color
of phosphor and causing different colors on the screen.
The purity problem is caused by some magnetic field that just locally
misaligns the electron beams with the shadowmask and phosphor. Ever tried to
put a magnet next to the electron gun?
Try it and you will see nicecolors.
But take care with magnets and a color CRT! You can easily pull the
shadowmask loose...
Al
B
Bill Jr
Guest
Try here: www.tritronicsinc.com
Do a part lookup and type in 143538611
Good Luck,
Bill Jr
P.S. This is a text only newsgroup. Attachments are frowned upon. If you
must show something please post a link to another place where the picture
can be found. Thank You.
"Philip Martin" <pjmartin.pyrenees@ntlworld.com> wrote in message
news:E5J1c.3202$zu.1256@newsfe1-win...
Do a part lookup and type in 143538611
Good Luck,
Bill Jr
P.S. This is a text only newsgroup. Attachments are frowned upon. If you
must show something please post a link to another place where the picture
can be found. Thank You.
"Philip Martin" <pjmartin.pyrenees@ntlworld.com> wrote in message
news:E5J1c.3202$zu.1256@newsfe1-win...
E
Eric
Guest
Usually, consumer transformers have a fuse line. If transformers get too
hot or over current, it will break. I did repair some transformers just
simply solder a wire to reconnect. Be sure the wire has same rating.
Eric
"Philip Martin" <pjmartin.pyrenees@ntlworld.com> wrote in message
news:E5J1c.3202$zu.1256@newsfe1-win...
hot or over current, it will break. I did repair some transformers just
simply solder a wire to reconnect. Be sure the wire has same rating.
Eric
"Philip Martin" <pjmartin.pyrenees@ntlworld.com> wrote in message
news:E5J1c.3202$zu.1256@newsfe1-win...
J
Jay Levitt
Guest
In article <rltf40l1o353q22pvpiba6g6hsbutoa2ir@4ax.com>,
jadney@vwtype3.org says...
fairly clean, but did not follow that to its logical conclusion: "Boy,
that fan sure is quiet. You can hardly tell it's even... oh." With
that evidence of my powers of observation, and the caveat that this is
probably my first serious component-level troubleshooting project...
I did some experimenting with my Fluke 867B DMM/pseudo-scope on the fan
card. The card is getting a pretty steady 14.91V on the +15V input, but
other than that, the readings seemed to bear no relationship to what was
supposed to be seen:
The non-grounded end of R8058: was 3.39V and climbing slowly, should be
0.8V.
Pin 3 of the fan: was 4.28V and dropping slowly, should be 1.6V.
Pin 4 of the fan: was 3.84V, s/b 1.6V.
Pin 7 of the fan: was 4.81V, s/b 1.6V.
Q8067 base: was 14.78, s/b 14.5V.
Between C8064 and R8054: was 14.78V, s/b 5.4V.
So something is wrong with this board. I'm not really sure what to do
now.. should I just start desoldering components at random and seeing
what doesn't meet spec? I've tried testing in place but of course the
interconnections are throwing off most of the readings. Is there one
particular component that could fail and give me these results? The
theory-of-operation section on the fan is small and unhelpful on this
matter, and there's no troubleshooting flowchart for it.
Of course, my limited knowledge of electronics doesn't help; I'm not
even clear why I should see a fixed voltage coming out of the
transistor-capacitor network (is that the right term?), since the output
of the transistor should be temperature-dependent, but perhaps the
capacitor plays some role in this...
Maybe I oughta buy the calibrated, warranted 465B on eBay (listing for
only $70 more than I paid for this, of course) and save this one for
parts later when I know what I'm doing! I didn't really need the DM44
anyway...
--
Jay Levitt |
Wellesley, MA | Hi!
Faster: jay at jay dot eff-em | Where are we going?
http://www.jay.fm | Why am I in this handbasket?
jadney@vwtype3.org says...
Good call. I had noticed the fan filter, and even observed that it was
fairly clean, but did not follow that to its logical conclusion: "Boy,
that fan sure is quiet. You can hardly tell it's even... oh." With
that evidence of my powers of observation, and the caveat that this is
probably my first serious component-level troubleshooting project...
I did some experimenting with my Fluke 867B DMM/pseudo-scope on the fan
card. The card is getting a pretty steady 14.91V on the +15V input, but
other than that, the readings seemed to bear no relationship to what was
supposed to be seen:
The non-grounded end of R8058: was 3.39V and climbing slowly, should be
0.8V.
Pin 3 of the fan: was 4.28V and dropping slowly, should be 1.6V.
Pin 4 of the fan: was 3.84V, s/b 1.6V.
Pin 7 of the fan: was 4.81V, s/b 1.6V.
Q8067 base: was 14.78, s/b 14.5V.
Between C8064 and R8054: was 14.78V, s/b 5.4V.
So something is wrong with this board. I'm not really sure what to do
now.. should I just start desoldering components at random and seeing
what doesn't meet spec? I've tried testing in place but of course the
interconnections are throwing off most of the readings. Is there one
particular component that could fail and give me these results? The
theory-of-operation section on the fan is small and unhelpful on this
matter, and there's no troubleshooting flowchart for it.
Of course, my limited knowledge of electronics doesn't help; I'm not
even clear why I should see a fixed voltage coming out of the
transistor-capacitor network (is that the right term?), since the output
of the transistor should be temperature-dependent, but perhaps the
capacitor plays some role in this...
Maybe I oughta buy the calibrated, warranted 465B on eBay (listing for
only $70 more than I paid for this, of course) and save this one for
parts later when I know what I'm doing! I didn't really need the DM44
anyway...
--
Jay Levitt |
Wellesley, MA | Hi!
Faster: jay at jay dot eff-em | Where are we going?
http://www.jay.fm | Why am I in this handbasket?
J
Jim Yanik
Guest
Jay Levitt <jay+news@jay.fm> wrote in news:MPG.1ab44746271fa9d98971f@news-
central.giganews.com:
enough.There's a thermistor that controls fan speed,not the xstr.The driver
IC fails,and also the motor itself.Motor bearings also wore out,too.
I'd try to replace it with a simple miniature 12V fan and maybe a dropping
R (it runs on 15V unreg,IIRC) or even a 3-terminal regulator IC.You would
probably have to modify the rear plastic panel for such a fan.
--
Jim Yanik
jyanik-at-kua.net
central.giganews.com:
IIRC,The fan assembly for the 465/B is a Hall-Effect motor,and failed often
enough.There's a thermistor that controls fan speed,not the xstr.The driver
IC fails,and also the motor itself.Motor bearings also wore out,too.
I'd try to replace it with a simple miniature 12V fan and maybe a dropping
R (it runs on 15V unreg,IIRC) or even a 3-terminal regulator IC.You would
probably have to modify the rear plastic panel for such a fan.
--
Jim Yanik
jyanik-at-kua.net
J
Jay Levitt
Guest
In article <Xns94A4DA049855Cjyanikkuanet@204.117.192.21>,
jyanik@abuse.gov says...
would still be right, no?
that but somehow edited it out. The transistor gets +15V in, and the
base is attached directly to the thermistor IIRC, so I'm not sure why
the manual says there's a specific voltage on the output.
it's not a typical exhaust fan. More like a water wheel, and I can't
quite figure out the airflow. Hmm.
--
Jay Levitt |
Wellesley, MA | Hi!
Faster: jay at jay dot eff-em | Where are we going?
http://www.jay.fm | Why am I in this handbasket?
jyanik@abuse.gov says...
Yep, it is.. but if the motor itself were failing, the voltages to it
would still be right, no?
Right, but the thermistor drives that transistor.. sorry, I had said
that but somehow edited it out. The transistor gets +15V in, and the
base is attached directly to the thermistor IIRC, so I'm not sure why
the manual says there's a specific voltage on the output.
Yeah, probably.. not sure I've seen a fan quite like this one, though -
it's not a typical exhaust fan. More like a water wheel, and I can't
quite figure out the airflow. Hmm.
--
Jay Levitt |
Wellesley, MA | Hi!
Faster: jay at jay dot eff-em | Where are we going?
http://www.jay.fm | Why am I in this handbasket?
R
Rich Andrews.
Guest
Jay Levitt <jay+news@jay.fm> wrote in news:MPG.1ab49bcd925b7ed4989720
@news-central.giganews.com:
sucks, not blows.>
r
--
Nothing beats the bandwidth of a station wagon filled with DLT tapes.
@news-central.giganews.com:
The fan is not an exhaust fan but an intake fan. In other words the fan
sucks, not blows.
>r
--
Nothing beats the bandwidth of a station wagon filled with DLT tapes.
J
Jim Adney
Guest
On Sat, 6 Mar 2004 20:39:05 -0500 Jay Levitt <jay+news@jay.fm> wrote:
IIRC, that board, etc, is pretty hard to get to on the 465B. Mine was
a bit noisy and I just decided to live with it.
465B, but that's the one I have. BOTH are very good scopes, however.
-
-----------------------------------------------
Jim Adney jadney@vwtype3.org
Madison, WI 53711 USA
-----------------------------------------------
;-)
Does the fan blade turn freely?
IIRC, that board, etc, is pretty hard to get to on the 465B. Mine was
a bit noisy and I just decided to live with it.
The DM44 really isn't much of a bonus these days. I'm partial to the
465B, but that's the one I have. BOTH are very good scopes, however.
-
-----------------------------------------------
Jim Adney jadney@vwtype3.org
Madison, WI 53711 USA
-----------------------------------------------
J
Jay Levitt
Guest
In article <glbl40h4acdrqgpq16v9e607ijd6vghagd@4ax.com>,
jadney@vwtype3.org says...
on the fan board that are accessible through holes in the board next to
it, but I couldn't separate the board from the fan blade. I took off
the whole back cover (which required the purchase of an impact
screwdriver since the screws were all stuck) and then discovered all I
had to do was remove a set screw from the fan-blade shaft.
the 'B' model. I presume I will eventually need a parts scope anyway,
so maybe (since I already know this scope's out of calibration and I
don't have a calibrator or the skills to build one) I'll just buy a
calibrated one and use this as my parts scope. I certainly don't need
yet another multimeter, especially DC-only, but I had been told that the
DM4 was useful for its frequency counter.
I guess I could probably move the DM44 to the new scope.. anyone know if
that's an easy task?
--
Jay Levitt |
Wellesley, MA | Hi!
Faster: jay at jay dot eff-em | Where are we going?
http://www.jay.fm | Why am I in this handbasket?
jadney@vwtype3.org says...
Yep, the blade turns no problem manually.
Nah, more like hard to figure out how to get to. There are two screws
on the fan board that are accessible through holes in the board next to
it, but I couldn't separate the board from the fan blade. I took off
the whole back cover (which required the purchase of an impact
screwdriver since the screws were all stuck) and then discovered all I
had to do was remove a set screw from the fan-blade shaft.
Actually, this one's a 465B too - I had read enough to know to prefer
the 'B' model. I presume I will eventually need a parts scope anyway,
so maybe (since I already know this scope's out of calibration and I
don't have a calibrator or the skills to build one) I'll just buy a
calibrated one and use this as my parts scope. I certainly don't need
yet another multimeter, especially DC-only, but I had been told that the
DM4 was useful for its frequency counter.
I guess I could probably move the DM44 to the new scope.. anyone know if
that's an easy task?
--
Jay Levitt |
Wellesley, MA | Hi!
Faster: jay at jay dot eff-em | Where are we going?
http://www.jay.fm | Why am I in this handbasket?
N
nick
Guest
On Sun, 07 Mar 2004 02:39:43 -0500, Jay Levitt wrote:
Here's one for $59 ouch! http://sphere.bc.ca/test/tek-transformers.html
J
Jim Yanik
Guest
Jay Levitt <jay+news@jay.fm> wrote in
news:MPG.1ab49bcd925b7ed4989720@news-central.giganews.com:
the IC failing.I don't recall if that IC is still available or not.
--
Jim Yanik
jyanik-at-kua.net
news:MPG.1ab49bcd925b7ed4989720@news-central.giganews.com:
Well,both the motor and the drive IC failed often enough.Yours probably is
the IC failing.I don't recall if that IC is still available or not.
--
Jim Yanik
jyanik-at-kua.net
J
Jim Yanik
Guest
Jay Levitt <jay+news@jay.fm> wrote in news:MPG.1ab5111a5feb79b0989723@news-
central.giganews.com:
"freq counter".Check the DM44 manual specs.
Well,you have to remove and transfer the DM's floating power supply,that
PCB mounted in the center channel of the scope chassis,next to the CRT
neck,the ribbon cable to the power xfmr,and make REAL certain you don't
mis-connect the DM44 ribbon cables to the timing switch board;I have a DM44
PCB that had that done and it fried the time functions,so I made it into a
standalone DMM,using two of the DM plastic covers back to back.
Other than that,it's not very hard.
--
Jim Yanik
jyanik-at-kua.net
central.giganews.com:
DM44's time,1/time functions are limited in accuracy.It's not really a
"freq counter".Check the DM44 manual specs.
Well,you have to remove and transfer the DM's floating power supply,that
PCB mounted in the center channel of the scope chassis,next to the CRT
neck,the ribbon cable to the power xfmr,and make REAL certain you don't
mis-connect the DM44 ribbon cables to the timing switch board;I have a DM44
PCB that had that done and it fried the time functions,so I made it into a
standalone DMM,using two of the DM plastic covers back to back.
Other than that,it's not very hard.
--
Jim Yanik
jyanik-at-kua.net
M
MarkC
Guest
Do you know anything about the internal design of these STK730's? I
thought that they were all identical accept for the wattage. When I
checked a new STK730-150 there is a short between pins 4 & 5. When I
checked a new STK730-030 there is NO SHORT between pins 4 & 5. Both 030
& 150 are used in the 35" Thomson TVs so I was wondering what is going
on here.
Mark
thought that they were all identical accept for the wattage. When I
checked a new STK730-150 there is a short between pins 4 & 5. When I
checked a new STK730-030 there is NO SHORT between pins 4 & 5. Both 030
& 150 are used in the 35" Thomson TVs so I was wondering what is going
on here.
Mark
J
JohnAce
Guest
Found out it was the Eprom. Replaced it and got my picture back. No sound
though. I had to go into the service menu and change some parimeters
though. I had to go into the service menu and change some parimeters
R
RonKZ650
Guest
I never checked for shorts, but the chips are interchangable. I checked for
current draw, running temperature, regulated B+ voltage ect between the 2 and
found the differences very minimal. Either will work.
Ron
current draw, running temperature, regulated B+ voltage ect between the 2 and
found the differences very minimal. Either will work.
Ron
J
john
Guest
Change that 47 mfd cap between it and the HOT.
kip
--
"Watch the return E-Mail addy its false"
"RonKZ650" <ronkz650@aol.comnospam> wrote in message
news:20040331231541.01536.00000453@mb-m15.aol.com...
kip
--
"Watch the return E-Mail addy its false"
"RonKZ650" <ronkz650@aol.comnospam> wrote in message
news:20040331231541.01536.00000453@mb-m15.aol.com...