By H. Mark Bowers — Revisions to FCC Part 76 Rules were released in April of this year. Significant changes were included in this release, including the rewording of some test procedures and standards, QAM carrier limits for aeronautical frequency notification.
Read MoreBy H. Mark Bowers — Preparation for AC design calculations requires a diagram of all amplifiers (system actives) in a tree-branch configuration as was shown in Part One of this series
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By H. Mark Bowers — Many technicians struggle with AC design, particularly in the area of proper power supply placement and loading. AC design involves concepts and principles that we don’t use in every day system maintenance or operation.
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By H. Mark Bowers — I believe this exercise raises the issue of how one is to perform accurate field strength measurements at higher LTE frequencies, where there is a low-level leak from the HFC plant (especially QAM).
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By H. Mark Bowers – Newer leakage detection systems are now available that measure at dual frequencies. While {the} present FCC required leakage detection frequency range remains in the 108 MHz to 137 MHz aeronautical band, measurements at higher frequencies can be revealing and may eventually be required
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By H. Mark Bowers – In my last column we examined the importance of scalar testing, definitions of various terms, equipment required, and examined waveforms of actual insertion loss and isolation measurements using a spectrum analyzer and tracking generator.
Read MoreBy H. Mark Bowers – As noted in Part One, FCC Proof-of-Performance testing is required once every six months in systems with over 1,000 subscribers: first during January or February, the ‘coldest’ months of the year; and then again during July or August, the ‘hottest’ months of the year.
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