NotTaR of Television Sets : Psychodelic color                       
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Psychodelic color

The means colors that are not normal and that adjustment of the user controls is not able to correct it so that all colors of the picture are properly displayed at the same time. For example, you are unable to get any yellows or blues in scenes that should have these colors..

Make sure the user color and tint controls have not been accidentally turned while cleaning or purposedly misadjusted by small (or large) kids.

Perform the user setup described in the section: User picture adjustment.

Confirm that the source is not a weird color video - try another channel or a tape.

Verify that this is not a missing color problem - one of the primary R, G, or B, has disappeared. If so, refer to the section: Intermittent or missing colors.

Once these have been eliminated, you are left with the following possibilities:

  1. Defective part around the chroma chip/circuit. Misadjusted color oscillator.

  2. Bad connections or short circuit in area of chroma chip/circuit.

  3. Defective chroma chip (don't suspect this first just because it is probably very expensive).

  4. Bad degauss circuit resulting in lack of degauss or abrupt termination of degauss current rather than smooth tail off. The CRT is not being properly demagnetized and color purity is totally messed up.

  5. Bad CRT - the shadow mask has been damaged and it is impossible to properly adjust purity across the screen.

A service manual or Sams', DMM, and scope will help greatly in attempting to troubleshoot this unless it is an obvious bad connection. For (1)-(3), try prodding the main board around the chroma chip with an insulated tool to see if you can restore normal color. For (4) try manually degaussing (see the section: Degaussing (demagnetizing) a CRT. If this clears up the colors until at least when it is power cycled, then a degauss problem is likely.

Something as simple as a bad resistor or inductor can be the cause - don't immediately suspect the most expensive and difficult to replace part.

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