Oscillator - Help Needed

 

Does anyone have an oscillator for MT4 that is similar to the description below that I could use as a model or maybe have the exact oscillator that they would be willing to share.

I want to be able to use a time in the market as the "zeroline". Lets say 1300 GMT. Ideally this would be adjustable. From this point, I want to be able to plot the closing price (difference) as a line that oscillates around the zero line (1300 GMT Close).

Any help would be appreciated. I am just learning MT4 coding and it is difficult for me at this point.

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