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Jeff did your school upgrade to digital cable? Just a thought maybe the amp is not passing the entire bandwidth
I Swear I did not touch anything 
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We just have regular cable everywhere.
Jeff Moss
Moss Communications
Computer Repair-Networking-Cabling
MBSWWYPBX, JGAE
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One of the problems we find is that sometimes tha amps are pumping too much power into the system. A 40db amp can be cranked to put out 46 db or better at the output. The length of your cable run will attenuate the signal somewhat, but without a signal level meter you're just guessing. I'm not sure of the exact number (I'd have to ask my son), but I suppose you want to have 10db or less at the set. We've tried to bypass the amp to clean up the signal temporarily (before we bought a signal level meter) and it sort of works with analog sets. Won't work with digital, which are much more particular about their level.
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Rover is correct. Too much signal is just as bad as too little. Also, the position of the amp is important. It needs to be at the begining to "push" not where the signal already down in the dumps and it's noise figure comes into play.
The range you want each set to see is 0 to +10db. Actually "digital" is much more forgiving. An analog set will gradually turn to snow as the signal is decreased and is subject to interference. Digital will maintain the same picture quality down to a point then it will pixilate then nothing.
-Hal
CALIFORNIA PROPOSITION 65 WARNING: Some comments made by me are known to the State of California to cause irreversible brain damage and serious mental disorders leading to confinement.
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We always targeted for a +3db at the end of the customers drop since our company (in the old days) charged for extra sets connected to the system. That way if the customer installed a splitter and multiple runs of coax they had lousy signal. This was done by installing the correct tap at the mainline splitter.
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We always aimed for +10 so that we could install a 4 way if necessary.
-Hal
CALIFORNIA PROPOSITION 65 WARNING: Some comments made by me are known to the State of California to cause irreversible brain damage and serious mental disorders leading to confinement.
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We charged for a 4way, back in the bucket I went 
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Jeff,
As a response to your posting regaurding the FIX.
I wanted to mention the Input signal to the amp. If you were able to bypass the amp totally and feed out to the TV's and get good pictures, your problem was probably "Overdrive" at your amp.
Too much signal hitting any "Active" device will cause a worst picture than LOW signal.
Also, as mentioned, with proper signal meters and sweep equipment, these problems can be identified fairly quickly.
Kirk Herron A mistake on your part does not constitute an emergency on my part. CCSG, Inc. www.ccsgweb.com
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