Slowly reddening picture; short term fix?

[Jon Danniken]

Hello,

I have a three year old television (Emerson from Wal*Mart) which has been
slowly turning red over the last year or so. I am assuming this is due to
the low quality tube, and that I really should just go out and buy a decent
set.

Nonetheless, I would like to possibly improve it, if only for the time
being.

There are three pots on the yoke, R, G, and B. Will adjusting these help
(even for a short time), and how should I go about doing this (ie, turn the
red down, turn the green and blue up, or both)? Also, will fiddling with
the RGB pots on the yolk throw anything else out of whack that would require
some knowledge and testing to calibrate correctly?

BTW: I am familiar with the dangers present inside of a television set, and
take full responsibility for my actions.

Thanks for any suggestions you are willing to offer,

Jon

 

[Homer J Simpson]

There are three pots on the yoke, R, G, and B. Will adjusting these help
(even for a short time), and how should I go about doing this (ie, turn
the
red down, turn the green and blue up, or both)?

Mark the current settings and try small adjustments.

Also, will fiddling with
the RGB pots on the yolk throw anything else out of whack that would
require
some knowledge and testing to calibrate correctly?

No, they are there for a reason.

 

[Jon Danniken]

Hello,

I have a three year old television (Emerson from Wal*Mart) which has been
slowly turning red over the last year or so. I am assuming this is due to
the low quality tube, and that I really should just go out and buy a decent
set.

Emerson EWT2721 if anyone is interested in the model number.

Jon

 

[RJ]

What happens is that the Green and the Blue become weak and the Red
takes over. Or any combination. It can happen to any color.


I usualy end up checking the tube with a tube checker. And find the the
Green and blue have digresed. Rejuvinating helps but yes it dose
shorten the tube life. But since you are going to toss it anyway whats
a few less years.
Make sure you use a plastic tunning tool when you adjusting the
controls on the neck board.

RJ

 

[tvguy]

About the only way that you will improve the color on this set is t
turn these up abit to try to get a normal black and white pictur
with the color control turned down. This will help for awhile

 

[Just Another Theremin Fan]

I shouldn't really encourage this but you might well find a current
limiting resistor or 2 in series with the tube heaters. Short one or
both out to boost the heater voltage and therefore the cathode
output

 

[Just Another Theremin Fan]

What happens is that the Green and the Blue become weak and the Red

takes over. Or any combination. It can happen to any color.

The blue gun works hardest and is usually the first to go followed
by the red then green.

 

[Sam Goldwasser]

Hello,

I have a three year old television (Emerson from Wal*Mart) which has been
slowly turning red over the last year or so. I am assuming this is due to
the low quality tube, and that I really should just go out and buy a decent
set.

Nonetheless, I would like to possibly improve it, if only for the time
being.

There are three pots on the yoke, R, G, and B. Will adjusting these help
(even for a short time), and how should I go about doing this (ie, turn the
red down, turn the green and blue up, or both)? Also, will fiddling with
the RGB pots on the yolk throw anything else out of whack that would require
some knowledge and testing to calibrate correctly?

No, as long as you mark the original settings as someone else mentioned.

But there should be 2 sets of 3 pots - one set for background (brightness)
and one set for gain (contrast).

You should probably try only the red pot(s) first.

By "yoke", do you mean the PCB on the neck of the CRT? These pots
would not likely be attached to the deflection yoke.

BTW: I am familiar with the dangers present inside of a television set, and
take full responsibility for my actions.

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Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

 

[Jon Danniken]

No, as long as you mark the original settings as someone else mentioned.

But there should be 2 sets of 3 pots - one set for background (brightness)
and one set for gain (contrast).

You should probably try only the red pot(s) first.

By "yoke", do you mean the PCB on the neck of the CRT? These pots
would not likely be attached to the deflection yoke.

Yes, on the little board connected to the back of the picture tube.

Thanks,

Jon

 

[Jon Danniken]

What happens is that the Green and the Blue become weak and the Red
takes over. Or any combination. It can happen to any color.


I usualy end up checking the tube with a tube checker. And find the the
Green and blue have digresed. Rejuvinating helps but yes it dose
shorten the tube life. But since you are going to toss it anyway whats
a few less years.
Make sure you use a plastic tunning tool when you adjusting the
controls on the neck board.

Thanks, RJ, I do have a set of plastic adjustment tools (bought from
RatShack ~ 20 years ago).

Jon

 

[Jeff Hackler]

Hello,

I have a three year old television (Emerson from Wal*Mart) which has been
slowly turning red over the last year or so. I am assuming this is due to
the low quality tube, and that I really should just go out and buy a decent
set.

Nonetheless, I would like to possibly improve it, if only for the time
being.

There are three pots on the yoke, R, G, and B. Will adjusting these help
(even for a short time), and how should I go about doing this (ie, turn the
red down, turn the green and blue up, or both)? Also, will fiddling with
the RGB pots on the yolk throw anything else out of whack that would require
some knowledge and testing to calibrate correctly?

BTW: I am familiar with the dangers present inside of a television set, and
take full responsibility for my actions.

Thanks for any suggestions you are willing to offer,

Jon

DON'T YOU KNOW THAT TVS HAVE A KNOB CALLED TENT ON THEM. PLAY WITH YOUR
PRICK INSTEAD OF THAT KNOB AND YOU WON'T HAVE FUCKED UP COLOR.

 

[[email protected]]

This is an Emerson tv set. They use a poorly designed AKB circuit for
the bias (on many models) and pots for the gain.
If the tube is weak then the low lights will be off first once it is
outside of spec for the AKB circuit.

Some earlier models used service menu for bias and pots for drive.

 

[Freddy Krueger]

Hello,

I have a three year old television (Emerson from Wal*Mart) which has
been slowly turning red over the last year or so. I am assuming this
is due to the low quality tube, and that I really should just go out
and buy a decent set.

Nonetheless, I would like to possibly improve it, if only for the time
being.

There are three pots on the yoke, R, G, and B. Will adjusting these
help (even for a short time), and how should I go about doing this
(ie, turn the red down, turn the green and blue up, or both)? Also,
will fiddling with the RGB pots on the yolk throw anything else out of
whack that would require some knowledge and testing to calibrate
correctly?

BTW: I am familiar with the dangers present inside of a television
set, and take full responsibility for my actions.

Thanks for any suggestions you are willing to offer,

Jon

I have one long term suggestion. Throw it in the trash and buy a Sony HDTV.

 

[tvguy]

Just Another Theremin Fanwrote
I shouldn't really encourage this but you might well find a curren

limiting resistor or 2 in series with the tube heaters. Short on o
both out to boost the heater voltage and therefore the cathod
outpu

I would not attempt doing this. You could loose the tube all togethe
if you don`t know what you are doing. I would just turn up th
controls on the crt socket or take it to the repairshop to see i
they have a crt rejuvenator to correct this problem

 

[Jeff Hackler]

I shouldn't really encourage this but you might well find a current

I would not attempt doing this. You could loose the tube all together
if you don`t know what you are doing. I would just turn up the
controls on the crt socket or take it to the repairshop to see if
they have a crt rejuvenator to correct this problem.

TAKE A TV WORTH 25 CENTS TO A REPAIR SHOP. JUST TURN UP THE CONTROLS ON
THE CRT SOCKET.

 

[tvguy]

Jeff Hacklerwrote
tvguy wrote

Just Another Theremin Fanwrote
I shouldn't really encourage this but you might well find curren
limiting resistor or 2 in series with the tube heaters. Short on
o
both out to boost the heater voltage and therefore the cathod
outpu

I would not attempt doing this. You could loose the tube al togethe
if you don`t know what you are doing. I would just turn up th
controls on the crt socket or take it to the repairshop to see i
they have a crt rejuvenator to correct this problem

TAKE A TV WORTH 25 CENTS TO A REPAIR SHOP. JUST TURN UP THE CONTROL
ON THE CRT SOCKET.[/quote:6a39c8a09e

I think this tv is worth abit more than 25 cents there buddy. I woul
service this type of tv if it was brought into me and would fix it a
a fair price