Oh lawd. We've expanded our downstream carrier from one frequency (657 MHz) to two (657, 687 MHz). Unfortunately, nobody told us about the change (what's new right?) Now I've got neighborhoods where the bulk of the modems lock on at 657 MHz and I'm starting to get little pockets of overflow that are locking onto 687 MHz. The only problem is I've swept and balanced all actives ensuring my EOL's are within max/min spec on sweep and MER is at or above 35 dB.
Today, I go to a customer's house to work an SRO that got turned over to me. I find out his modem is locking on at 687 MHz (which was when I actually first heard of this happening). 687 MHz has a downstream MER of 29.5 dB. Meanwhile, my 657 MHz carrier is looking sharp with a signal level that is two dB higher and my MER is 35.1.
I called the head end and it was then that I was told we have the additional frequency to allocate for overflow problems in anticipation of the DOCSIS 3.0 upgrade. In other words, if 657 fills and bandwidth is maxed, modems will start rolling over to 687. Sounds like a great idea... in theory. However, now I've got to re-certify every active in my area (12 nodes - 4200 modems)? That's a lot of freaking actives to recheck AFTER we've already rolled out the new "solution" to everyone's problems. Any advice or things I should look for?
- J_r0kk
Docsis 3.0
Member #: 66963
Registered: 3/18/2009
Posted:
129
Name:
Jay Rokk
Name:
Jim Milliken
Company:
Cable One
Occupation:
Regional Engineer - II
Location:
Louisiana
Personal:
mid 50s
Experience:
~24 years
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