If you are having problems with that specific frequency, I would remove the carrier and look at the noise floor and do a CTB test with a peak-hold. Possibly you may have encountered some other beats that may be causing you problems caused from elsewhere.
Where are you testing for the "unstable carrier"? Is the testing location at the modulator itself or at a combined point past the combiner? If it is at the modulator itself, change the frequency (if agile) and see if it happens all through the band. I would also look for any AC grounding problems between racks and chassis as the higher in frequency you go, the more unstable and unpredictable the carrier when subjected to bad coaxial grounds and floating voltages.
Another possiblity cound be a poor 120VAC with unstable voltage that changes with air conditioner (or whatever) kicking on/off causing high load voltage drop.
What type of meter(s) are you checking with? The Stealth has been historic for measuring video peaks and will normally flux about .5dB or more depending on the sensitivity of the unit and how much "HUM" it sees along the way. I would use a spectrum analyzer for a more accurate reading.
I hope that this has helped you in some way.
Good Luck!
Greg Tobin
Interactive Broadband Technical Services, LLC
Re: ? Regarding the use of an analog carrier @ 859
Member #: 7190
Registered: 1996-2001
Posted:
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Name:
Greg Tobin
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Greg Tobin
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Interactive Broadband Technical Services
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HFC Engineer/Consultant
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