said by koitsu:
As I understand it, "the node" refers to the cable node/segment (which correlates with a small or large geographic area, i.e. a "segment" of the cable network from which customers get their drops) while "head-end" means where (or near where) the CMTS is. So this is why I put "at the node" in quotes because I'm not sure what exactly he meant by what he said, given the terminology I've learned. I often get the impression all these techs (service and line/network) "re-use" terms to describe multiple things.
The node is a glorified media converter essentially. It takes the optical feed from the hubsite and converts it to the coax running around neighborhoods. The CMTS generally exists at the hubsite level not the headend level. Some might reuse headend to mean hubsite but with everyone having their own ways of saying things it's really anyone's guess.
Think of the headend as the main aggregation point for a geographic area. It feeds many different hubsites that themselves feed many different nodes. There may be more than one headend for an area depending on size, Atlanta has two that I know of: Stone Mountain and Vinings but I believe there are two others that probably came from other cable system acquisitions and general expansion.
said by koitsu:
4. Line tech stated that after chatting with fellow techs about this problem, one reminded him of this issue happening in San Carlos (about 15 miles from here) but he himself had forgotten about it. He then told me the story about having to replace a long run of cable up there which looked fine but obviously was taking noise. I asked how they managed to figure out it was that cable. He said there's a device they have which allows them to look for leakage, but it's a long and drawn out task because it requires 2 people and a lot of walking.
That is a cable leak detector and there can be vehicle and hand-held versions. Looks like they have really changed since the last one I had my hands on. The one I had really resembled a radar gun and had two telescoping antennas coming out each side. It could require two people but sometimes will be done with one depending on what they are looking for.
If they are looking for signal egress (signal leaking out) that can be done with one person driving around until he/she gets to the general area and then going on foot. If they are looking for signal ingress (signal making it's way in), that really does require two people. One to sit at your house and/or designated test points with a sensor and the other to drive around broadcasting a specific signal that sensor will be looking for.
Suffice it to say, depending on the area this issue could be fixed either from you pushing them or the FCC/FAA pushing them. If you live near a major airport or are in a major flight path, the FAA will do flyovers and identify hot spots that need attention. As such, your area may get flagged and fixed eventually even if you don't push them (not that I'm saying you shouldn't try, just that it may one day "fix itself" so to speak).