Much to my surprise something or someone somewhere lit a little fire under Comcast today. Appt was scheduled for Sunday but they moved it up to this Friday afternoon. A plant maint tech was even here at the same time working at the tap from his bucket.
Maybe it was our municipal franchise authority contacting the Comcast government rep? Heck, I got four calls today between a CC tech supervisor, CC executive support person I've been working with, CC advanced tech support, and finally a premise tech who was dispatched (the guy who basically told me he's the "go-to guy" when there's difficult problems no one else resolves). Apparently my issue and personal persistence is fairly well-known at the local Comcast office among the techs. Not sure that's necessarily a good thing, but I have been respectful and polite at all times. Hopefully they realize my only goal is to get this working/stable and receive periodic followup while they actively work an acknowledged issue...
Findings today were: Our drop and inside wiring are fine. Zero ingress from those elements. (tech said it was a perfect flat-line) No surprise since its been tested numerous times already and several components replaced at least once. There is however a known ingress issue impacting parts of the node. Apparently some folks are more severely affected than others and its intermittently severe to the point of it being an outage. That's good news in some ways -- it lends credibility to what we're experiencing in addition to the CC ticket documentation showing lousy upstream SNR.
Now here's the interesting part and I'd be curious to hear some insight from knowledgeable folk frequenting this forum. The maintenance tech seemed fairly convinced its due to power company related RF near one of the active line amps down the road about 1/4 mile. He mentioned using an AM radio that in some spots the interference drowned out even regular station signals. He offered a suggestion that even though CC has notified and requested a dispatch from JCP&L, the power company has not yet done anything. There was a mention of a suspected power company grounding fault which CC absolutely cannot touch. I'm not an electrician or EE so have no existing personal knowledge to verify what that might actually mean. It sounds credible, but so would "you need to replace the ball bearings in your muffler!" to someone who has no clue about automotive mechanics.
Anyway, a quick drive around the area with the car's radio on didn't reveal anything unusual that my untrained ear can detect noise-wise. Static is static. And of course that means nothing..
However, I'd have no idea how to even go about articulating such a "problem" with JCP&L much less where its at or with what equipment. CC is continuing to work the trouble but this suggestion was offered as a way to get possibly faster attention from JCP&L. Meanwhile my device is now actively being monitored so CC can do further correlation.
It is true that an power company equipment issue such as a grounding problem can knock out an entire node? Is cable plant shielding that minimal & ineffective? If this is killing cable's upstream frequency range (~22Mhz to ~42Mhz), wouldn't emergency communications (fire dispatch and ops here for example use 33.74Mhz) as well as other over-the-air applications suffer?
This has now become quite a curious situation technically-speaking. As an aside I'm a bit more satisfied and a little more convinced they're not being dismissive simply hoping the problem goes away on its own. I understand complex problems rarely have simple fixes. But man, it sure took a bit of effort and energy to get this far! More to follow as the story continues.[edit: typo]