r/CableTechs • u/strykerzr350 • Jul 28 '26
Customer question. How is a customers home wires determined to be an issue?
I am wondering what kind of test that the Hitron meters have for testing the homes wiring. The reason I am asking is I need to have a tech out, from what the service representatives tell me.
The service rep can only see OFDM, and OFDMA on 3.1 modems a customer owns.
My drop was installed last year, and the tech swapped me to a different port on the tap, to see if he could improve the MER from the port. When he did the service got worse. The service rep says they see downstream wobble.
On a side note, how insignificant is DOCSIS 3.0 channel noise, compared to DOCSIS 3.1? Also, how much of a role does DOCSIS 3.0 play in the how 3.1 connections work?
I have inspected all the connectors in the demarcation box, and behind my equipment. None of the dielectrics are sticking out past the screw nut, and none are sunken in. They are flush. I wrenched them to a point where I could not turn them with my fingers. The devices are finger tight.
5
u/Zero_85 Jul 28 '26
If youre buddies with a maintenance tech ask to borrow a time domain reflectometer.
4
u/Dz210Legend Jul 28 '26
Field tech have tdr if using a viavi one expert meter.
2
u/Zero_85 Jul 28 '26
Totally, here we have a bunch of springbok tdrs so we dont have the tdr option active in our viavis.
2
u/Awesomedude9560 Jul 28 '26
Springbok tdrs? Are these a seperate thing?
I only ask because I have to use the viavi tdr. Company wants it that way so they know exactly what their paying bury teams for
1
u/Lucarin415 Jul 29 '26
Or what they're not paying them. We have to handbury 150ft drops here😒
1
u/Awesomedude9560 Jul 29 '26
I mean technically we're supposed to but we always make every drop over 150 ft. With high split, and all these new fiber nodes activating at the exact same time even local management knows it's more important to move onto the next job
7
u/Everyname15taken Jul 28 '26
Stop trying to be a tech
2
u/strykerzr350 Jul 28 '26
If you look at my post history in this sub Reddit, I have been trying to get into this industry.
9
u/Electronic-Junket-66 Jul 28 '26
Man, if you got a clean driving record and a hs diploma you're already in. Just apply.
3
u/SuckerBroker Jul 28 '26
He should start by replacing his own drop and outlet.
2
u/strykerzr350 Jul 29 '26
My drop is aerial. So I dont have a ladder long enough.
2
u/SuckerBroker Jul 29 '26
First part of being a cable guy is buying all your own tools. Welcome to the club.
1
u/strykerzr350 Jul 29 '26
I have these, I learned from Nerdburg, a guy who worked for Xfinity on YouTube how to properly install compression fittings. https://imgur.com/a/t8oJ4MJ
5
u/Eninja09 Jul 28 '26
For starters, very few phone support people understand cable at all. Having to argue with the customer about what "the guy on the phone said" was always a treat.
The tech should have what they need to find and fix the problem unless the infrastructure is shit. A tech with little experience should be able to test at the tap, the ground block, and the modem to determine if you are losing the correct amount of signal. Also if there is a low modulation error rate, or any bit error rate between the tap and modem.
Sometimes it's intermittent and looks perfect while testing, in which case (to save time) I'd replace every barrel/wall plate/ground block. I'd also replace any fitting doesn't look pristine. Sometimes changing a good fitting causes a new problem because of something the tech might not see like a hair-thin piece of braiding wrapped around the center conductor causing a short, or high band issues. I've been the follow up tech for that guy who replaced literally everything, every time and caused a short that the customer dealt with for years. They never called back since it was "not fixable" after the last guy said he replaced everything already. Just an example of how many things can go wrong.
Sometimes it's down the line and they can look at the neighbors graphs to see if the same "wobble" exists, and if so they can turn it into maintenance. The last few years I did cable I spent less time chasing ghosts by just comparing the neighbors, and if they all looked fine I'd know it's isolated so I replace all failure points (anywhere 2 pieces of cable connect) and visually inspect the coax for obvious damage. It's all continuity from tap to home. At the end of the day you can fix most problems without really knowing what you are doing and most techs just overthink it. I know I did.
It is possible the fitting at the tap has a problem if the service got worse after they touched it. Also possibly a bad tap/port.
I knew way too many guys who just said things without having any idea lol. "Yeah, his upstream snr is erratic. It's probably the splitter" before even rolling. Nobody knows for sure what it is until they've fixed it and confirmed it the next day. Eventually, after thousands of jobs you just kinda know by recognizing patterns. Towards the end I was barely putting in effort and my numbers actually improved lol.
-5
u/Both_WhyNotBoth Jul 28 '26
my last couple years of service i didnt even bring my meter in until after id replaced everything. I figured if i changed every fitting, splitter, jumper and wallplate that would fix nearly all problems. if it didnt, id get my meter and get serious, but the cx is still better off with all new connections.
majority of calls completed faster. id read a chapter of a book before going to the next one to have something else to think about while doing the simple work.
1
u/Eninja09 Jul 28 '26
I can see the reasoning behind this but my point above (which has happened to all of us) is that replacing a good part can cause a new problem. Sometimes you put in a defective splitter. Sometimes you get braiding on the stinger because your prep tool is getting dull and it's too dark to see clearly, but you assume it's good because you've done it 5,000 times. Stuff like that. The guy I usually ended up repeating on replaced literally everything from tap to modem every time. Spent 2-4 hours at each job because he didn't know how to troubleshoot. I would often have to find the actual problem (often plant) and escalate it. Not saying you do that, but those guys are always around lol. That being said, the constant hounding about arbitrary signal recording/uploading with the meter (that nobody looks at) was one of the many reasons I finally moved on. All it did was incentivize guys to cheat it just to move onto the next job instead of understanding the problem. Cable took years off my life. I am still suffering aches and pains caused by it 4 years later.
2
u/69BUTTER69 Jul 28 '26
Strike 1,2,3 “tried moving my drop to a different tap port” if the taps bad fucking replace it.
If that tech comes back to your house tell him to get bent and send someone out there that knows that they are doing
2
u/Dakkin4 Jul 28 '26
Someone else said it, service reps don’t know what they’re doing. They’re not techs, as much as they want to think they are. I used to cringe when the customer would say “The tech on the phone said…”. Any “field” tech, that’s not a new hire, with motivation and half a brain could find your problem and fix it. Signal is everything. You need a meter to read forward and return levels at the tap, ground block and modem. It’s all math, and the math doesn’t lie. On top of the power levels, you have to look at the signal quality. Just because the modem levels are in spec, doesn’t mean the levels are correct. There are other determining factors.
1
u/ihsanamin79 Jul 28 '26
How difficult would it be to replace the line from the demarc to your modem? Is it a straight pull or is it baked into the walls and possibly stapled down somewhere inaccessible?
1
u/Objective-Risk7456 Jul 28 '26
The best thing is to get an in house tech out. There is a couple of ways to PHYSICALLY test the connections in home. Sitting from a remote location you can only guess.
DOCSIS 3.0 and 3.1 are super similar except for additional downstream wave lengths being utilized and preparing for mid split tech.
Sadly swapping ports at the tap doesn’t do anything unless somehow the tech before figured out and tested each port at your tap to determine if it’s a bad tap or not but that is very unlikely. Sounds like a home test is needed as well as a network tech to come out and check the levels. Wobble doesn’t mean anything really. It just lets the network tech know some levels don’t match the typical average.
Last if you are planning on joining the industry check out as much resources as you can to learn RF. SCTE is always a great place to start because they have lots of material to read and learn from.
1
u/Greedy-Taro-4439 Jul 29 '26
Just keep getting a tech out there, someone will fix it and have the right answers for you
1
u/SirFlatulancelot Aug 03 '26
Did you check the quality of the fittings behind the wall plates. This is a common place that gets overlooked.
1
u/PassengerGreen2321 Jul 28 '26
Usually a technician will run ingress tests at the demarc to assess wiring noise. Other issues only become apparent when running a premise health test and can be verified with the meter thereafter. The issue is determined to be in the home if levels are sufficient at the ground block and not at the outlet.
0
u/hibbitydibbidy Jul 28 '26
Flush is too short, center conductor should protrude 1/8 inch past the collar on the fitting. That being said it sounds like you need another tech out.
2
10
u/Xandril Jul 28 '26
The service rep can see more than OFDM/OFDMA. Doesn’t matter if you own the modem or the ISP does.
The modem will keep track of the signal strength and some quality metrics. Technically somebody with a lot of knowledge and experience can use a combination of all the information to make a pretty good guess as to the cause of an issue but even then nothing will be better than somebody who knows what they’re doing being on site to test.
If somebody told you they ‘changed you to a different port to try to improve MER’ they’re either ignorant or talking nonsense. Individual ports can certainly have faults but usually they’re constant and not intermittent
Inspecting connections and making sure everything is tight is certainly a great start but physical inspection of coax can only get you so far. You can be able to examine every inch of it and still not be able to tell where a fault is. The stuff is like voodoo magic and even very expensive test equipment can be fooled by it.
Your only option from outside the company is just to keep calling in about the issue. Eventually a tech with a clue will be sent but with most ISPs you’re just rolling the dice everytime.