Very old GE TV dies- what could be wrong?

[Stan]

I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box,
cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov.
1984). I bought it used in 2000. I don't have or want cable TV-- I only
watch free, broadcast type TV shows. [I've had this TV connected for maybe
the past 1.5 months to a cheap Magnavox TV converter box.]

The other day I turned on the TV, it worked fine for a few minutes and
then suddenly goes dead. This pattern can be repeated after a short rest
of the TV: it goes on, picture looks fine and sound is OK and then suddenly
dies -- goes totally silent and black -- after a few minutes running.

What could be wrong with it? Does this sound like it's the main picture
tube which is shot or something else? [This TV must have been a
costly, state-of-the-art one when it came out in 1984, so I guess the best
electronics for its time were used in its construction.]

Tell me what you think or suspect.


Thanks

[To contact me, drop one 'i'.]

 

[[email protected]]

I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box,
cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov.
1984). I bought it used in 2000. I don't have or want cable TV-- I only
watch free, broadcast type TV shows. [I've had this TV connected for maybe
the past 1.5 months to a cheap Magnavox TV converter box.]

The other day I turned on the TV, it worked fine for a few minutes and
then suddenly goes dead. This pattern can be repeated after a short rest
of the TV: it goes on, picture looks fine and sound is OK and then suddenly
dies -- goes totally silent and black -- after a few minutes running.

What could be wrong with it? Does this sound like it's the main picture
tube which is shot or something else? [This TV must have been a
costly, state-of-the-art one when it came out in 1984, so I guess the best
electronics for its time were used in its construction.]

Tell me what you think or suspect.

Thanks

[To contact me, drop one 'i'.]

I suspect that it could be the power supply not the picture tube but I
can be wrong.

 

[CJT]

I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box,
cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov.
1984). I bought it used in 2000. I don't have or want cable TV-- I only
watch free, broadcast type TV shows. [I've had this TV connected for maybe
the past 1.5 months to a cheap Magnavox TV converter box.]

The other day I turned on the TV, it worked fine for a few minutes and
then suddenly goes dead. This pattern can be repeated after a short rest
of the TV: it goes on, picture looks fine and sound is OK and then suddenly
dies -- goes totally silent and black -- after a few minutes running.

What could be wrong with it? Does this sound like it's the main picture
tube which is shot or something else? [This TV must have been a
costly, state-of-the-art one when it came out in 1984, so I guess the best
electronics for its time were used in its construction.]

Tell me what you think or suspect.


Thanks

[To contact me, drop one 'i'.]

One can't be certain, but I'll hazard a guess --

Assuming it's a color set, it'll have a protective circuit that shuts it
down (in order to avoid X-ray emissions) if the picture tube begins to
draw too much current. Either that circuit is failing/has drifted out
of tolerance, or something else causes the current draw to enter the
"danger" zone once the set warms up.

 

[stan74]

....... My next step
would be to observe just how it shuts down. Does it appear as if someone
just hit the off button?

Yes, the failure is exactly like someone hitting the OFF button.

Does it display any anomalies either sound or
picture-wise or does it again just look like it was turned off?

No anomalies-- it just goes off. However, just recently and only while
this problem has been going on, I've noticed that while the TV is briefly
working, a station *might* suddenly turn to static- just static sound and
no picture. I switch to another channel and all is OK with that one and
with the others. [We only get 6 free, broadcast TV channels in my city.]

Does the TV get its AC source from the converter?

No, and I've disconnected the TV from the Magnavox HD converter box. The
power comes thru the cord plugged into the wall outlet (via an extension
cord). Other things connected to this same outlet are fine: a box fan and
a clock.

If it just shuts off like you
turned it off I would first suspect the power supply then measure some
voltages therein to see what happens as/when it shuts down.

Thanks Meat Plow for your help. Since I never deal with or mess with
electronics, I might be able to find someone who knows how to do these
tests.

[To contact me, drop one ' i '.]

 

[gcd]

Hi,
apart form the other suggestions - don't forget to test the electrolytic
caps in the power supply. A dry electro could be the cause too.

Greg

 

[hr(bob) [email protected]]

Yes, the failure is exactly like someone hitting the OFF button.

No anomalies-- it just goes off. However, just recently and only while
this problem has been going on, I've noticed that while the TV is briefly
working, a station *might* suddenly turn to static- just static sound and
no picture. I switch to another channel and all is OK with that one and
with the others. [We only get 6 free, broadcast TV channels in my city.]

Does the TV get its AC source from the converter?

No, and I've disconnected the TV from the Magnavox HD converter box. The
power comes thru the cord plugged into the wall outlet (via an extension
cord). Other things connected to this same outlet are fine: a box fan and
a clock.

Thanks Meat Plow for your help. Since I never deal with or mess with
electronics, I might be able to find someone who knows how to do these
tests.

To the seasoned vet those sets are pretty straight forward. I used to do
GE warranty among others back in the 80s. I wouldn't sink much money in it
however.- Hide quoted text -

- Show quoted text -

The first thing to do is try another tv set in place of your set. if
it also fails after a few minutes, then it is the convertor box that
is dying. The freezing of the picture is typical of a convertor
problem. Magnavox is made by Funai which is the cheapest convertor
and has gotten a very bad reputation due to the high failure rate of
their convertors.

Bob Hofmann

 

[Chuck]

I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box,
cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov.
1984). I bought it used in 2000. I don't have or want cable TV-- I only
watch free, broadcast type TV shows. [I've had this TV connected for maybe
the past 1.5 months to a cheap Magnavox TV converter box.]

The other day I turned on the TV, it worked fine for a few minutes and
then suddenly goes dead. This pattern can be repeated after a short rest
of the TV: it goes on, picture looks fine and sound is OK and then suddenly
dies -- goes totally silent and black -- after a few minutes running.

What could be wrong with it? Does this sound like it's the main picture
tube which is shot or something else? [This TV must have been a
costly, state-of-the-art one when it came out in 1984, so I guess the best
electronics for its time were used in its construction.]

Tell me what you think or suspect.


Thanks

[To contact me, drop one 'i'.

This television came with a service manual attached in a box on the
back. If you could scan and upload the schematic to media fire or a
binary group, it might jog my memory. I worked for a high volume GE
repair center when that set was new and have probably seen most common
failures. Chuck

 

[jakdedert]

I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box,
cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov.
1984). I bought it used in 2000. I don't have or want cable TV-- I only
watch free, broadcast type TV shows. [I've had this TV connected for maybe
the past 1.5 months to a cheap Magnavox TV converter box.]

The other day I turned on the TV, it worked fine for a few minutes and
then suddenly goes dead. This pattern can be repeated after a short rest
of the TV: it goes on, picture looks fine and sound is OK and then suddenly
dies -- goes totally silent and black -- after a few minutes running.

What could be wrong with it? Does this sound like it's the main picture
tube which is shot or something else? [This TV must have been a
costly, state-of-the-art one when it came out in 1984, so I guess the best
electronics for its time were used in its construction.]

Tell me what you think or suspect.


Thanks

[To contact me, drop one 'i'.

This television came with a service manual attached in a box on the
back. If you could scan and upload the schematic to media fire or a
binary group, it might jog my memory. I worked for a high volume GE
repair center when that set was new and have probably seen most common
failures. Chuck

And your reply jogged my memory a bit. Didn't a lot of those GEs have
problems with solder joints on large lugged connections? ISTR a couple
of those I worked on back in the 80's (for friends; I was never a
commercial tech) which would just 'die'. The fix was to rework all of
the solder joints where large 'stuff' was attached to the main PCB.

It seems they didn't get them hot enough, and the larger components
(especially chokes and transformers) sinked away so much heat that the
joints were not viable. In fact, I recall one on which I had to resort
to my 100/150 watt Weller gun to get enough heat going....

jak

 

[Chuck]

I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box,
cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in
Nov. 1984). I bought it used in 2000. I don't have or want cable TV-- I
only watch free, broadcast type TV shows. [I've had this TV connected
for maybe the past 1.5 months to a cheap Magnavox TV converter box.]

The other day I turned on the TV, it worked fine for a few minutes and
then suddenly goes dead. This pattern can be repeated after a short
rest of the TV: it goes on, picture looks fine and sound is OK and then
suddenly dies -- goes totally silent and black -- after a few minutes
running.

What could be wrong with it? Does this sound like it's the main picture
tube which is shot or something else? [This TV must have been a costly,
state-of-the-art one when it came out in 1984, so I guess the best
electronics for its time were used in its construction.]

Tell me what you think or suspect.


Thanks

[To contact me, drop one 'i'.



This television came with a service manual attached in a box on the
back. If you could scan and upload the schematic to media fire or a
binary group, it might jog my memory. I worked for a high volume GE
repair center when that set was new and have probably seen most common
failures. Chuck

And your reply jogged my memory a bit. Didn't a lot of those GEs have
problems with solder joints on large lugged connections? ISTR a couple of
those I worked on back in the 80's (for friends; I was never a commercial
tech) which would just 'die'. The fix was to rework all of the solder
joints where large 'stuff' was attached to the main PCB.

It seems they didn't get them hot enough, and the larger components
(especially chokes and transformers) sinked away so much heat that the
joints were not viable. In fact, I recall one on which I had to resort to
my 100/150 watt Weller gun to get enough heat going....

I recall feed through points on GE TV boards of that era having sub
standard soldering.

Your right, but that issue was resolved by the time the PP chassis
came out except for the tuner assembly. Chuck

 

[Chuck]

I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box,
cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov.
1984). I bought it used in 2000. I don't have or want cable TV-- I only
watch free, broadcast type TV shows. [I've had this TV connected for maybe
the past 1.5 months to a cheap Magnavox TV converter box.]

The other day I turned on the TV, it worked fine for a few minutes and
then suddenly goes dead. This pattern can be repeated after a short rest
of the TV: it goes on, picture looks fine and sound is OK and then suddenly
dies -- goes totally silent and black -- after a few minutes running.

What could be wrong with it? Does this sound like it's the main picture
tube which is shot or something else? [This TV must have been a
costly, state-of-the-art one when it came out in 1984, so I guess the best
electronics for its time were used in its construction.]

Tell me what you think or suspect.


Thanks

[To contact me, drop one 'i'.

This television came with a service manual attached in a box on the
back. If you could scan and upload the schematic to media fire or a
binary group, it might jog my memory. I worked for a high volume GE
repair center when that set was new and have probably seen most common
failures. Chuck

And your reply jogged my memory a bit. Didn't a lot of those GEs have
problems with solder joints on large lugged connections? ISTR a couple
of those I worked on back in the 80's (for friends; I was never a
commercial tech) which would just 'die'. The fix was to rework all of
the solder joints where large 'stuff' was attached to the main PCB.

It seems they didn't get them hot enough, and the larger components
(especially chokes and transformers) sinked away so much heat that the
joints were not viable. In fact, I recall one on which I had to resort
to my 100/150 watt Weller gun to get enough heat going....

jak

There was something that would break loose in the switched power
supply or the horizontal section and the width pot would burn up and
the set would go dead. It was a very common problem but without the
schematic, I can't remember what it was. Chuck

 

[stan74]

This television came with a service manual attached in a box on the
back.

Yes Chuck, that's right. There's a cut out window in the plastic box on
the back of the TV. Thru the window one easily sees the instructions with
words that say the instructions/manual/schematics are only available if
the TV box is opened up, something I've not yet done due to what I write
below.

If you could scan and upload the schematic to media fire or a
binary group, it might jog my memory. I worked for a high volume GE
repair center when that set was new and have probably seen most common
failures. Chuck

When I turned on the TV two days ago, it was totally dead: it wouldn't
even start up. So it seems the symptoms I told you about when I started
this thread were early signs of eventual TV death which is now the case.
Is it still worthwhile to see the schematics? I'd have to open up the TV
box and then look somewhere in town for a scanner. [I don't own one.]

 

[Chris F.]

I had a fancy '85 RCA with the exact same problem, and the cause took some
time narrow down. Turns out the horizontal output transistor was shorting
after it warmed up, causing the switching power supply to shut down (without
blowing fuses etc - wish they still built stuff this well). Replacing the
transistor fixed the set.
If you aren't familiar with the inner workings of a TV, I'd recommend
taking it to a professional. A competent and honest tech should be able to
fix it for a reasonable price.
The most bizarre cause of this problem I ever saw was on an old
Electrohome from the early 80's. Believe it or not, the primary winding on
the flyback was opening after the flyback warmed up - I never saw anything
like that before or since.

I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box,
cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov.
1984). I bought it used in 2000. I don't have or want cable TV-- I only
watch free, broadcast type TV shows. [I've had this TV connected for
maybe
the past 1.5 months to a cheap Magnavox TV converter box.]

The other day I turned on the TV, it worked fine for a few minutes and
then suddenly goes dead. This pattern can be repeated after a short rest
of the TV: it goes on, picture looks fine and sound is OK and then
suddenly
dies -- goes totally silent and black -- after a few minutes running.

What could be wrong with it? Does this sound like it's the main picture
tube which is shot or something else? [This TV must have been a
costly, state-of-the-art one when it came out in 1984, so I guess the
best
electronics for its time were used in its construction.]

Tell me what you think or suspect.


Thanks

[To contact me, drop one 'i'.]

One can't be certain, but I'll hazard a guess --

Assuming it's a color set, it'll have a protective circuit that shuts it
down (in order to avoid X-ray emissions) if the picture tube begins to
draw too much current. Either that circuit is failing/has drifted out
of tolerance, or something else causes the current draw to enter the
"danger" zone once the set warms up.