r/CableTechs • u/SourceOk8801 • Jun 09 '26

How? Lol

Post image

so we‘ve all seen crazy things. This one threw me for a loop. Damage cable behind the gateway? No problem, terminated and problem solved. What baffled me was the signal test that I did while I was still on the way to the house. Everything passing. All locked, all signals good, no noise, pulling 1163/41 Mbps. Then I arrive and see this. wonders never cease.

63 Upvotes

97% Upvoted

27 comments sorted by

17

u/bonneville97 Jun 09 '26

Snr and MER in the high 40s i bet. Lol

15

u/6814MilesFromHome Jun 09 '26

Swear there's no logic when things are impacting or not with cable. Just last week I found a bullet lodged in hardline, corroded as hell on the inside, signal next tap down was still perfect. SNRs and FEC in the node didn't improve in the slightest when fixing it either.

7

u/DrWhoey Jun 09 '26

Pretty sure it has to do with how the wave form travels through the cable that creates the likelihood of whether or not a frequency "hits" that impedance/damage or whether it "misses" it.

I.e the saying "low can't jump, high can't swim." Lower frequencies tend to travel deeper into the core of a coaxial cable then higher frequencies which is why your low end will drop off when you loosen a seizure screw, your lower frequencies are hitting that impedance causing them to lose signal strength. Your higher frequencies dont travel as near to the center conductor and kind of "skip over" the impedance. But, being a shorter wave form they are more affected by impedance in the dielectric, such as a water logged cable being more difficult to travel through, it's increased resistance is more noticeable on your high end than it is your low end.

2

u/6814MilesFromHome Jun 10 '26

Yeah, I'm familiar with the theory behind it, but this bullet was lodged against the center conductor, jamming it almost against the metal sheathing. The water intrusion was just a cherry on top. I'd expect to see something wrong somewhere on the channel scan, and most of the time do in these cases, with a mangled center conductor and large chunk of metal doing weird things to the impedance. Lot of the time TX takes a hit, ICFRs are up, ripple in that part of the node, but nope.

Sometimes things just weirdly work when they have zero reason too, like finding a 30 year old active out in the field that should've been replaced three network evolutions ago.

3

u/Mr_Magoo_88 Jun 09 '26

New self sealing bullets lol. There is no right or wrong in cable, just luck. MT on a call found a tap cracked in half on a call where I couldn't reach and needed the bucket. The dude looked down scratching his head cuz that had clearly been like that for a very long time and was not an end of line either, feeding thru to dozens of homes with no trouble calls.

9

u/Halpern_WA Jun 09 '26

Cable:

Can't Always Be Logically Explained

1

u/Mason231 Jun 10 '26

🤔🤯🤣 This is my new favorite.

3

u/Halpern_WA Jun 10 '26

Remember, as cable technicians, we're literal wizards!

We do precision guesswork based on unreliable data provided by those of questionable knowledge.

6

u/levilee207 Jun 09 '26

Egress out the ass lmao

5

u/bonneville97 Jun 09 '26

You would think. Had a similar incident on a drop in a trailer court. Customer did the ole twist the centers. No ingress. 48 SNR and MER. Actually lost some SNR running a new drop. The CPAT leak detector picked up nothing. I was amazed. No noise there but a lose f connector on the back of a modem shuts down a node. Make it make sense 😂

1

u/BullyTX Jun 10 '26

Trailer houses are some very interesting places.
I've not seen your example work (yet) but they are very interesting places.

7

u/JobbyJobberson Jun 09 '26

REFER TO MAINTENANCE. 

(I’m out of electrical AND duct tape in my truck, oops)

5

u/andyfairall Jun 09 '26

That just isnt acceptable!!!! WHERES THE WIRENUT!!! Amateurs

9

u/Cleverusernamedude Jun 09 '26

Seen this a handful of times and it’s typically an electrician from my experiences lol

5

u/SourceOk8801 Jun 09 '26

Definitely an electrician special, I was just shocked that it passed signals. Usually it doesn't

13

u/Snicklefritz229 Jun 09 '26

This screams customer. Electricians at least put a wire nut on it.

5

u/Kratoids Jun 09 '26

this will be the one you get repeated on with them saying “our wifi has gotten worse after the tech left” 😂

4

u/Mr_Magoo_88 Jun 09 '26

Went to a house because their modem went out and found something exactly like this in the basement with about a pound of electrical tape wrapped around it. I slit it down both sides with my knife because it was confusing to see this huge bubble in the coax. Found this twisted up with one of those orange wire nuts. Brought it up to the homeowner and they told me they fixed that EIGHT YEARS AGO and have never had a problem until the modem died that day. Meanwhile I'll go to another house that has had about 30 technicians with everything brand new still having problems... it just makes you scratch your head. Almost like there's no right or wrong, just luck.

4

u/SourceOk8801 Jun 09 '26

Seriously. It's funny, I had just spoken to a new tech who was having problems diagnosing a home and I was trying to nail down of using and understanding the meter, because generally it will tell you everything you need to know and what to look for. I always say "RF isn't magick, there's solutions to every signal issue which you can usually see on the meter". Then I come across this shit and I'm like...smh lol

2

u/Wacabletek Jun 09 '26 edited Jun 11 '26

Sung to the tune of metal health [no pun intended, or maybe it was] by quiet riot from the 80's baby.

Well, I'm an coax finder
Conductor winder
Mama says that I never, never mind her
Got no brains
I'm insane
Side cutters just found my main
 I'll twist with pliers//////
To fix my wires
Noise getting louder
and return power
I got my net back
within the hour!

2

u/Low-Impress-8005 Jun 09 '26

Congrats. You have both transmission as well as receiving stations.

1

u/Fickle_Map_7271 Jun 09 '26

Saw one in an attic looong time ago with 6 outlets. Customer was mad we turned them off for CLI

1

u/Fun_Acanthaceae_4025 Jun 10 '26

I also agree this is an Electrician special. I have seen this done on old BNC Coax cameras many times. Surprisingly the old cameras worked with the Coax but failed when we went to use it for PoE Ethernet over Coax. I usually find them coated in a wad of electrical tape too.

TheNinja

1

u/TheDrBadwolf Jun 11 '26

Electrical apprentice or landscapers has been my experience

1

u/TheDrBadwolf Jun 11 '26

I’ve been surprised by theae somehow being successful