Toshiba TV29C90 problem; Image fades to black...

"Steve Vitale" <spam@newsie.net> wrote in message
news:pine.GSO.4.10.10410291420390.2610-100000@spirit.gcrc.upenn.edu...
| Hi all, I have an sharp XG-E3500U lcd projector that i'm trying to repair,
| I've purchased a copy of the service manual (email me off list if you'd
| like a copy) and have a pretty good idea of how things are working. when i
| got the unit, the main fuse on the power board was blown and the person
| who gave it to me suspected that the power supply was bad. when i replace
| the fuse and power up, the lamp arcs 2-3 but never lights. the fuse blows
| immediately afterward. my assumption is that either the warm-up arc isn't
| able to ignite the lamp because it's bad, or that the lower voltage
| componant supplied by the ballast is isn't there so the thing keeps
| pulsing then blows a fuse. Will a bad bulb cause a fuse to blow because it
| won't conduct a current after being hit with the warm up arc? I figured
| I'd send a message to the list to get an opinion before i spend $300 on a
| new bulb.. maybe i need to focus more on trouble shooting the ballast. Is
| there an easy check for visual or electronic signs of a bad metal halide
| bulb? Thanks for any help, Steve

That's backwards. I'd suspect the ballast, not the lamp. Is the ballast
inductive or solid state? I'd try hooking up a 100 W light bulb as a test to
replace the lamp, disconnecting the starter system if possible. If the lamp
glows fully or not at all I'd suspect the ballast.

N
 
That's backwards. I'd suspect the ballast, not the lamp. Is the ballast
inductive or solid state? I'd try hooking up a 100 W light bulb as a test to
replace the lamp, disconnecting the starter system if possible. If the lamp
glows fully or not at all I'd suspect the ballast.

N
I assume that it's an electronic ballast as it uses transistors to limit
Click to expand...
current as opposed to a coil. i assume those should be keeping things
from reaching a current where a fuse would blow? i think this is starting
to make a bit more sense.
Thanks
 
Have a look at <a
href="http://members.aol.com/JURB6006/delco/delcocass.htm&gt;Delco "2000"</a href>

JURB
 
<a href="http://members.aol.com/JURB6006/delco/delcocass.htm">Delco "2000"&lt;/a
href&gt;

JURB
 
We all know it when we see it. It's got a fairly characteristic look to it
but ...

A) What, physically, is a cold solder joint?


and

B) What are the electrical characteristics of a cold solder joint?

TIA

Norm
 
"Searcher7@mail.con2.com" is not a valid email.


On 29 Oct 2004 08:31:55 -0700, Searcher7@mail.con2.com (Darren Harris)
wrote:


Okay.

Since there doesn't seem to be another way, can anyone refer me to
someone who may be able to build something like what I'm after?
Click to expand...
 
On Fri, 29 Oct 2004 13:33:55 -0500, John Fields wrote:

On 29 Oct 2004 08:31:55 -0700, Searcher7@mail.con2.com (Darren Harris)
wrote:

Okay.

Since there doesn't seem to be another way, can anyone refer me to
someone who may be able to build something like what I'm after?

---
What's a "split"?
Click to expand...
Apparently not just plain multiple displays, each with its own
"latch" button, all started and clocked together.

Cheers!
Rich
 
LOL!!!!!!!

"Lionel" &lt;nop@alt.net&gt; wrote in message
news:8id1o0lc2pqej1m05mmtukoe2e5fkocrdo@4ax.com...
Kibo informs me that "Fred" &lt;testing@testing1212mouse.com&gt; stated that:

I'm just wondering... if you call this up and get some gal jabbering in
Chinese at you, how do you know she's not just complaining about you not
mowing the lawn or fixing that leaky kitchen faucet -- like you hear at
home?

The spammer is probably selling the other side of the service to Chinese
women as a 1-900 tech-support service.

--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------
Click to expand...
 
"Norm Dresner" &lt;ndrez@att.net&gt; wrote in message
news:lvzgd.42732$OD2.32843@bgtnsc05-news.ops.worldnet.att.net...
|
| We all know it when we see it. It's got a fairly characteristic look to
it
| but ...
|
| A) What, physically, is a cold solder joint?

It is an unwetted connection between solder and other metals. Think blobs of
water on a greasy pan.


| and
|
| B) What are the electrical characteristics of a cold solder joint?

Variable. Sometimes they work for 10 years then fail. Usually they make
intermittent connection. Sometimes they make no connection at all without
external pressure.

N
 
"Steve Vitale" &lt;spam@newsie.net&gt; wrote in message
news:pine.GSO.4.10.10410291639190.18452-100000@spirit.gcrc.upenn.edu...
| &gt; That's backwards. I'd suspect the ballast, not the lamp. Is the ballast
| &gt; inductive or solid state? I'd try hooking up a 100 W light bulb as a
test to
| &gt; replace the lamp, disconnecting the starter system if possible. If the
lamp
| &gt; glows fully or not at all I'd suspect the ballast.
| &gt;
| &gt; N
| I assume that it's an electronic ballast as it uses transistors to limit
| current as opposed to a coil. i assume those should be keeping things
| from reaching a current where a fuse would blow? i think this is starting
| to make a bit more sense.
| Thanks

Much more likely one of those has punched through. Replace them or find a
way to test them under voltage.

N
 
On 29 Oct 2004 17:24:08 -0700, tuckmeng@hotmail.com (TuckMeng
Lam) wrote:

Hi,

Was dumb enough to buy a PC TV card that does not work with my TV
system (my TV system in Singapore is PAL B/G and the TV Tuner card
only does PAL D/K). It seems that only 1 metal box needs to be
changed. (a rectangular part that is connected to a socket for the
antenna) Can anyone advise if it's an easy thing to change the card to
work on PAL B/G by using spare parts from other TV cards? (thinking of
getting a 2nd hand card just to rip off the TV tuner part).

Reason why I don't want to replace the card is because the card has
other features in it (realtime MPEG4 compression etc) that I like.
Besides, I have limited budget. Only the TV part doesn't work. I get
TV pictures but static instead of sound.

Grateful for any good advice. Please email me at tuckmeng at
hotmail.com
Click to expand...
Get a cheap VCR and connect the composite video and audio from it
to the inputs on your capture card.
 
have not seen inside one as yet.
if it has belts try a new belt and check
the gears for damage and if there timed or
alined right.

"Shane" &lt;darkpheonix@gmail.com&gt; wrote in message
news:e7cdddb6.0410290747.1e7a2b96@posting.google.com...
long story short, i have a ps2 and the lil grabber thingi that comes
up and spins the cd(know what i mean) spins, but it won't come up to
the cd. i've opened it up, and it spins, and it does what it's suppose
to, except the spinner doesn't elevate to get the cd. any help would
be appreciated.
Click to expand...
 
On Fri, 13 Aug 2004 23:59:08 GMT, jpero@sympatico.ca (Jason D.) wrote:

Keep in mind that I have schematic for this model.

Will not power up with PC connector plugged in (this is power for 40V,
-40V, 15V, -15V and few grounds) for the convergence board. Like I
said, checked for shorts and could not find any.
Led starts at solid red (normal for this design for standby. Turn it
on, LED modulates quickly few cyles not like blinks) then stays red.
If I unplug that PC (power for convergence), it will do the LED
flicker thing and change green and tv comes up fine.

If I had convergence board completely unplugged from rest of chassis,
there is no flicker in LED when I turn it on. Goes from red straight
to green.
Click to expand...
Hey, everybody on this group including me failed that! The sneaky
cause was the SMPS IC (STK711-550) ingoring the optisolator's frantic
signaling for more power more power! And power is low but unplug that
PC plug voltages comes up ok. That's sneaky, what more, 1 in 20
chances with PC plugged set comes up. I was watching at that set
while on with PC plugged in deep thought when I realized pulsing
picture was in sync with trob of our worn out air compressor. Clack
(shiver) clack (shiver) clack (shiver)... AHA, had my head together
with my coworker looking at power supply schematic and he suggested
that I look at feedback on STK side. 7V instead of appox 3V. We
agreed to go for STK711-550 IC. Fixed!

Unplugging convergence board made TV "working" is what made me chasing
the convergnce board in circles. Arf arf! That hungry dog ate up all
the estimate and went over. :-( That is very upsetting PLUS owner is
on the horn (HONK HONK) daily driving my boss nuts. Grrr.

With SMPS working right, the LED changed from RED *STRAIGHT* to GREEN
instantly at press of power button, nothing like that kind of flutter
or funky things and with PC plugged in.

On yours, go for that pesky STK711-550! Growls...

Cheers,

Wizard
 
I think TV cards can change TV system from NTSC to all PAL versions even to
SECAM. HAve you checked the programs options?
 
Whats the Model Number and what was the original fault.
Please explain the fault to us so as we can help you.


kip
 
On Fri, 29 Oct 2004 22:29:37 GMT, "Norm Dresner" &lt;ndrez@att.net&gt;
wrote:

We all know it when we see it. It's got a fairly characteristic look to it
but ...

A) What, physically, is a cold solder joint?
Click to expand...
If I remember correctly, a good solder joint should create an actual
chemical/physical change/bond at the surfaces of the lead and the
solder pad. The metals actually join chemically. A cold solder joint
likely would not accomplish this. Just a guess, sort of an educated
one, maybe.

Tom

and

B) What are the electrical characteristics of a cold solder joint?

TIA

Norm
Click to expand...
 
I had the same problem with the advnet q2035a TV. At that same time I had a
working same model. I switched the eeprom and that fixed it. Previously I
had built an eeprom programmer, so I just copied it and it worked fine.
 
On Sat, 30 Oct 2004 11:19:13 -0400, "john"
&lt;va3mmTAKEOUTTHIS@niagara.com&gt; wrote:

Whats the Model Number and what was the original fault.
Please explain the fault to us so as we can help you.


kip

The TV is a 1992 kv27-xbr35.
Click to expand...

The symptom was intermittent horizontal dark and light
banding on the picture about 1/2 inch wide.
When I sprayed the component in question with the cooler spray,
the picture got worse, suggesting to me, that this was a
failing component.

As I said, when I soldered in the new part and put it back
together, the TV won't turn on now. I haven't touched it since,
I thought I would wait for some feedback first.

Either the part is bad, it's back to front (although I'm not even sure
if it makes a difference with this part), or I screwed something else
up getting the board out and in.

Any thoughts appreciated.

Dave
 
Quoting Team Goon [teamgoon@ilovespam.comcast.net], that posted to
sci.electronics.repair on Fri, 29 Oct 2004 13:49:25 -0400 under article
&lt;S9mdnefjEZZ-HB_cRVn-oA@comcast.com&gt;:
The idiot who was whining about top posting.
Top posting is the deault.
Click to expand...
A: Top posting.
Q: What is the most irritating thing on Usenet?

[]s
--
Chaos MasterŽ, posting from Brazil.
"People told me I can't dress like a fairy.
I say, I'm in a rock band and I can do what the hell I want!"
-- Amy Lee
http://marreka.no-ip.com | http://tinyurl.com/46vru | http://renan182.no-ip.org
 
Ok Best remove the chassis and get out you mag glass
and look for many bad solder joints.That part you changed
has nothing to do with what you describe.(Banding)
As far as the VDR goes either way it does not matter.

kip
 
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