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Slowly reddening picture; short term fix?

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

Reply to
Jon Danniken
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Mark the current settings and try small adjustments.

No, they are there for a reason.

Reply to
Homer J Simpson

decent

Emerson EWT2721 if anyone is interested in the model number.

Jon

Reply to
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.

RJ

Reply to
RJ

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

Reply to
tvguy

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

Reply to
Just Another Theremin Fan

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

Reply to
Just Another Theremin Fan

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.

:)

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Reply to
Sam Goldwasser

been

to

decent

help

the

with

require

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

Thanks,

Jon

Reply to
Jon Danniken

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

Jon

Reply to
Jon Danniken

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.

Reply to
dkuhajda

"Jon Danniken" wrote in news: snipped-for-privacy@individual.net:

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

Reply to
Freddy Krueger

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

or

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.

Reply to
tvguy

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

Reply to
Jeff Hackler

current

together

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

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

Reply to
tvguy

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