[Tig] Low Frequency EMI - 60Hz
Jan & Eileen
Sat May 24 21:43:36 BST 2003
XYZ controls, if I'm correct (in earlier Davinci's & 888) were being
activated at video rate, not film rate.... and that can be interpreted
As horizontal jitter..
[Watch me get jumped now!!! :)]
From: tig-admin at tig.colorist.org [mailto:tig-admin at tig.colorist.org] On
Behalf Of Wilf Giovanella
Sent: Saturday, May 24, 2003 2:19 PM
To: Alex Pimentel; tig at tig.colorist.org
Subject: Re: [Tig] Low Frequency EMI - 60Hz
Jeff Heusser supports the tig.
I have seen positional hum introduced into daVinci analog XYZ controls in a
machine. It shows up as a horizontal jitter. (like the jump scan days). I
excess control cable was coiled in the bottom of a rack. Mu-Metal solved
problem until the cable cut shorter and not coiled.
I have also seen image shift as much as 5% and a purity shift caused by
power lines. In this case it was induced into the monitors and TK scanning.
amount of shielding was able to eliminate the problem. The equipment was at
75 feet from the source. Street cars use DC. Normally DC surges are not as
dramatic, and the supply lines are together and the EMI from the + and -
With street cars and electric trollies one line overhead, the other is the
current is always surging and due to the distances between the EM sources,
pull and push the electron beam around the screen.
Deluxe | Sound and Picture
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