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Michael A. Terrell Michael A. Terrell is offline
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Default TV buzzes with overly white video

wrote:

A pad shouldn't help as the 'automatic gain control' will just push up
the gain to make up for the pad. If it's in an extremely high RF
condition, the pad might help but it's rare to get that much signal.

GG



Have you ever tried a pad? The AGC system in a TV is a very basic
system that is designed to keep the level within a range, and driving it
to the upper limit can cause sync buzz. I have seen complex AGC systems
with 14 op amps, and the DC offset was limited to 1.5 mV over the entire
range. It could maintain the output level to less than a .1 dB change
over the entire useful RF input range. You WILL NOT see a AGC system
like this in a consumer level receiver.


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Michael A. Terrell
Central Florida