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In the 7200 manual, it says the proj. has a phase control which changes the phase of the video signal. What does this do? Don't answer that it changes the phase of the video signal.


What would you see on changing the phase, and when would you have to use it?


Thanks.
 

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LOL, 'fraid of a junk answer?


All video display devices depend on one central clock signal, called the pixel clock. This synchronizes all video in the chain, from source to sink.


Most source devices (dvd, stb, etc) are too cheap to provide for adjusting the pixel clock, so it's left up to the projector (sink).


The pixel clock in the pj must match its source device in both freq and phase, in order to get a pixel-perfect image.


Freq is "the number of times per second a full cycle is completed", from 0 to 1 and back, expressed in Hertz/Hz/bps.


Phase means the temporal matching of a 0-to-1 transition in the sink with a 0-to-1 transition in the source, again contributing to a pixel-perfect image.


When freq and phase are mismatched between source and sink, you'll see artifacts like diagonal wavy lines across the screen, and 'non-coherant' pixels.


Since before you were born, there's been a circuit called a "phase-locked-loop", which has a free-running oscillator that is automatically matched in freq & phase to the source. All radios have this (except Recoton car radios... what a terrible brand), so they can follow the signal as it drifts.


I can understand the need to get the sink device's pixel clock close to the source (and the PLL would take over), but it's unclear to me the need for a phase adjustment at all. This implies that there is no PLL circuit in the sink?

Preposterous, but I have no other explanation.


Be advised that NO projectors seem to have a PLL for pixel clock, so the ability to adjust pixel clock freq & phase is a very desirable feature which many projectors lack. (Marantz)
 

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I see burnt has learned how to use the copy paste function
 

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LMAO.....too funny! :D


Happy Thanksgiving!


T
 
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