Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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Brian
 
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Default BAH! New (2 me) panasonic tube fading in and out

I just got a 27" panasonic TV a month ago. It's rather old, from 1993. It
had a blown speaker and I replaced it. It had a perfect picture until
recently.

It started to fade the picture to all black then back. It became more
frequent over the week. Now it doesn't turn on and I'm lucky if it fades in
for a couple seconds. Everything is perfect except for the black fading out
video. I googled for a bit and found no seemingly bad solder points on any
of the boards and i replugged in the connectors that I could get my hands
on. I resoldered the 7 or so points where the filament tube goes in to the
board.

Every time I take a look and poke around, maybe one out of 10 times the
picture will come back on for a couple seconds.

I just paid $40 for the nice tv (it was giving a perfect picture) and $30
for a speaker, now I'm crap out of luck with no picture!

Any thoughts other than to move on and get a new one?

Brian


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Tech Data
 
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Default BAH! New (2 me) panasonic tube fading in and out

Here's one option. Any competent tech shouldn't charge more than 50 to
60 dollars to take care of that, considering what we've had to reduce
our prices to as of late. That's still a beautiful product but, if it's
not worth that to keep it going, toss it.

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Brian
 
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Default BAH! New (2 me) panasonic tube fading in and out

Thanks for the thought, Tech Data.

I'm already in $70 for this TV after the speaker replacement. Considering
how old it is, I'm not sure if it's worth spending more money to have
someone repair it for me. I could find another TV used (maybe smaller and
newer) for around $40-50... but I hate to see this as a waste of $70, you
know what I mean!

Brian

"Tech Data" wrote in message
oups.com...
Here's one option. Any competent tech shouldn't charge more than 50 to
60 dollars to take care of that, considering what we've had to reduce
our prices to as of late. That's still a beautiful product but, if it's
not worth that to keep it going, toss it.



  #4   Report Post  
Baz
 
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Default BAH! New (2 me) panasonic tube fading in and out


"Brian" wrote in message
...
I just got a 27" panasonic TV a month ago. It's rather old, from 1993. It
had a blown speaker and I replaced it. It had a perfect picture until
recently.

It started to fade the picture to all black then back. It became more
frequent over the week. Now it doesn't turn on and I'm lucky if it fades

in
for a couple seconds. Everything is perfect except for the black fading

out
video. I googled for a bit and found no seemingly bad solder points on any
of the boards and i replugged in the connectors that I could get my hands
on. I resoldered the 7 or so points where the filament tube goes in to the
board.

Every time I take a look and poke around, maybe one out of 10 times the
picture will come back on for a couple seconds.

I just paid $40 for the nice tv (it was giving a perfect picture) and $30
for a speaker, now I'm crap out of luck with no picture!

Any thoughts other than to move on and get a new one?

Brian



Brian,

Sounds like it could be the picture tube heaters going on and off, as the
pix goes slowly to black then backup. I'd start looking for a dry joint
somewhere in the heater supply area.

My 10 cents worth of advice is don't start re-soldering everything in sight.
Find the bad joint first then you'll know for sure you've fixed it.

Barry


  #5   Report Post  
Brian
 
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Default BAH! New (2 me) panasonic tube fading in and out

Hi Barry. Thanks, but I'm no TV expert, although I love fixing things. I'm
not sure what you mean by joints. I searched the boards for markings of "H"
to indicate they are for the heater, but couldn't find any H's.

I got the picture working for an hour, at which point I turned it off and
its back to black when turned on.

"Baz" wrote in message
...

"Brian" wrote in message
...
I just got a 27" panasonic TV a month ago. It's rather old, from 1993. It
had a blown speaker and I replaced it. It had a perfect picture until
recently.

It started to fade the picture to all black then back. It became more
frequent over the week. Now it doesn't turn on and I'm lucky if it fades

in
for a couple seconds. Everything is perfect except for the black fading

out
video. I googled for a bit and found no seemingly bad solder points on
any
of the boards and i replugged in the connectors that I could get my hands
on. I resoldered the 7 or so points where the filament tube goes in to
the
board.

Every time I take a look and poke around, maybe one out of 10 times the
picture will come back on for a couple seconds.

I just paid $40 for the nice tv (it was giving a perfect picture) and $30
for a speaker, now I'm crap out of luck with no picture!

Any thoughts other than to move on and get a new one?

Brian



Brian,

Sounds like it could be the picture tube heaters going on and off, as the
pix goes slowly to black then backup. I'd start looking for a dry joint
somewhere in the heater supply area.

My 10 cents worth of advice is don't start re-soldering everything in
sight.
Find the bad joint first then you'll know for sure you've fixed it.

Barry






  #6   Report Post  
Baz
 
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Default BAH! New (2 me) panasonic tube fading in and out

Hi Brian again,

(I'll post on the top seeing how you did last time). If you are not familiar
with the innards of a TV, best you call in some help.

Basically what I was referring to is a faulty or cracked solder joint, going
intermittently open circuit. It could also be a cracked printed circuit
board track, or tube socket. It could even be a faulty picture tube heater,
but I'd honestly not put that at the top of the list. But it could be.

This type of fault, in my opinion, is best found with the TV turned on,
using a magnifying glass and an insulated "prod", rather than lots of test
equipment. Once again, if you're not familiar with being inside a TV and
the hazards involved DON'T DO IT! You could end up DEAD, or severely
injured (you really could, no joking).

Take the TV to a reputable repairer and fully describe the symptoms, and get
their opinion.

Take care.

Regards
Barry

"Brian" wrote in message
...
Hi Barry. Thanks, but I'm no TV expert, although I love fixing things. I'm
not sure what you mean by joints. I searched the boards for markings of

"H"
to indicate they are for the heater, but couldn't find any H's.

I got the picture working for an hour, at which point I turned it off and
its back to black when turned on.

"Baz" wrote in message
...

"Brian" wrote in message
...
I just got a 27" panasonic TV a month ago. It's rather old, from 1993.

It
had a blown speaker and I replaced it. It had a perfect picture until
recently.

It started to fade the picture to all black then back. It became more
frequent over the week. Now it doesn't turn on and I'm lucky if it

fades
in
for a couple seconds. Everything is perfect except for the black fading

out
video. I googled for a bit and found no seemingly bad solder points on
any
of the boards and i replugged in the connectors that I could get my

hands
on. I resoldered the 7 or so points where the filament tube goes in to
the
board.

Every time I take a look and poke around, maybe one out of 10 times the
picture will come back on for a couple seconds.

I just paid $40 for the nice tv (it was giving a perfect picture) and

$30
for a speaker, now I'm crap out of luck with no picture!

Any thoughts other than to move on and get a new one?

Brian



Brian,

Sounds like it could be the picture tube heaters going on and off, as

the
pix goes slowly to black then backup. I'd start looking for a dry joint
somewhere in the heater supply area.

My 10 cents worth of advice is don't start re-soldering everything in
sight.
Find the bad joint first then you'll know for sure you've fixed it.

Barry






  #9   Report Post  
Andy Cuffe
 
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Default BAH! New (2 me) panasonic tube fading in and out

On Mon, 07 Nov 2005 01:38:53 GMT, "Brian" wrote:

I just got a 27" panasonic TV a month ago. It's rather old, from 1993. It
had a blown speaker and I replaced it. It had a perfect picture until
recently.

It started to fade the picture to all black then back. It became more
frequent over the week.


If the picture is fading gradually in and out, check for the heater
glow in the neck of the CRT. If the heaters go out when the picture
fades out, you've found the problem. There's not much that can cause
that (usually either bad soldering, or an intermittent resistor).

Andy Cuffe

-- Use this address until 12/31/2005

-- Use this address after 12/31/2005
  #10   Report Post  
Brian
 
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Default BAH! New (2 me) panasonic tube fading in and out

Hi Andy. The glow comes on when the picture comes on, and the glow fades out
as the picture fades out.

I looked all over the board but found no bad solders that caught my eye.




"Andy Cuffe" wrote in message
...
On Mon, 07 Nov 2005 01:38:53 GMT, "Brian" wrote:

I just got a 27" panasonic TV a month ago. It's rather old, from 1993. It
had a blown speaker and I replaced it. It had a perfect picture until
recently.

It started to fade the picture to all black then back. It became more
frequent over the week.


If the picture is fading gradually in and out, check for the heater
glow in the neck of the CRT. If the heaters go out when the picture
fades out, you've found the problem. There's not much that can cause
that (usually either bad soldering, or an intermittent resistor).

Andy Cuffe

-- Use this address until 12/31/2005

-- Use this address after 12/31/2005



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