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Old TV caused village broadband outages for 18 months

bbc.com

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Re: Old TV caused village broadband outages for 18 months

#281

Post by Balgair »

Scoundreller wrote: post #279
robocat wrote: post #267

Earlier quoted context omitted.

> The Toronto eruv alone is estimated to cost $100,000 per year > But being difficult to maintain is kind of the point. Why not implement it as an optical fibre? Non-conducting and easy to continuously check that there are no breaks.

At least for fibre optic, I thought it required a carrier wire for rigidity? Dunno if they're okay with automated checking, it might make it too scalable and simple to be acceptable.

Additionally, you can't use electricity on the Sabbath [0]. Unless you come up with some very clever way to couple sunlight or candlelight (!) into the fiber-optic cable and then detect time of flight in a non-electronic and cheap way, then just going out and checking by eye is the best bet.

Great idea though! I'd always thought that looking at the phase of an electroni impluse would give you a good idea of how far along the path a break occurred, as the return signal's phase should be inverted at the break point and you can then use time of flight to infer the distance of the break.

[0] This is a hyper deep part of jewish law and there are many exceptions. Please consult your local rabbi before taking my word for anything.

Re: Old TV caused village broadband outages for 18 months

#282

Post by Animats »

And nobody has a spectrum analyzer.

The problem is that, although they're not expensive [1], reading one is complicated. You need to know what the spectrum usage is supposed to look like.

Cell towers ought to have interference detection built in. They're already software defined radios.

[1] https://www.alibaba.com/product-detail/Foxtech-Portable-Hand...

Re: Old TV caused village broadband outages for 18 months

#283

Post by justin66 »

BurningFrog wrote: post #278
justin66 wrote: post #277

Earlier quoted context omitted.

> One big problem with regulations is that even if they're beneficial when enacted, they will remain in force for many decades after the underlying reality has changed. We tend to avoid principles-based regulation in the US, but it's not destiny that regulations remain the same forever, even with our system. We certainly don't have to choose between that and not having any regulations at all (which isn't even an opti…

My impression is that regulations turn to legacy status more often than not. Not that I've conducted any scientific study to back that up. For radio spectrum you don't need any regulations or regulators. Just establish that radio frequencies in a certain area can be owned, and use general property right rules.

It's not really my area, but I feel like the distinction you're making between "regulations" and "general property right rules" is a bit like the distinction that is made at times between "fees" and "taxes."

Re: Old TV caused village broadband outages for 18 months

#284

Post by Scoundreller »

Balgair wrote: post #281
Scoundreller wrote: post #279

Earlier quoted context omitted.

At least for fibre optic, I thought it required a carrier wire for rigidity? Dunno if they're okay with automated checking, it might make it too scalable and simple to be acceptable.

Additionally, you can't use electricity on the Sabbath [0]. Unless you come up with some very clever way to couple sunlight or candlelight (!) into the fiber-optic cable and then detect time of flight in a non-electronic and cheap way, then just going out and checking by eye is the best bet. Great idea though! I'd always thought that looking at the phase of an electroni impluse would give you a good idea of how far a…

Might be okay to use electricity if they're validating before the Sabbath? Isn't that how it works?

Dunno how they handle breaks during the Sabbath...

But I'm 100% out of my league here.

Re: Old TV caused village broadband outages for 18 months

#285

Post by mturmon »

JonathonW wrote: post #269
mturmon wrote: post #265

Earlier quoted context omitted.

> But that nice shiny metal lamp you've got? It's got the neutral bonded to the body... Another commenter pointed this out, but I have to chime in as well: no. Not true. The neutral is NOT bonded to the exterior body of a metal lamp. Not even on old fixtures built in the 1960s. The old fixtures, if they were metal, were often not grounded, i.e. the lamp might not be connected by a 3-prong plug (hot, neutral, ground).…

> The thing that does happen when switching the neutral wire on a lamp is that doing so will energize the more-accessible "outer ring" of the Edison female receptacle rather than the less-accessible "center pin". This means that if you change the bulb with the switch on, you'd be more likely to contact the hot "outer ring". Also, in most cases, the switch is only across (the wire that is supposed to be) the hot lead-…

> ...you'll still get a shock regardless of the state of the switch...

oops, yes, good point.

Re: Old TV caused village broadband outages for 18 months

#286

Post by 8bitsrule »

robocat wrote: post #266
saltspork wrote: post #116

Earlier quoted context omitted.

Open neutrals are no joke, here’s a good analysis of a similar situation that caused a house fire: https://www.electrical-forensics.com/Open-Neutral/Open-Neutr... Here in Australia the coax connection from the street typically goes through a galvanic isolator to avoid this situation, rather than being bonded to the earth.

What do you mean by “galvanic isolator”? Link to coax example device? I’ve never heard the term before and a quick google is showing something irrelevant. NZer, so the language barrier exists!

Hadn't heard the term before. Looks like its two diodes in parallel, pointing opposite directions, in a very-expensive box. Blocks low-voltage DC flow while allowing higher-voltage AC currents to pass. Looks like maritime usage is common.

http://www.yandina.com/galvanicIsolator.htm

Re: Old TV caused village broadband outages for 18 months

#287

Post by richardwhiuk »

kube-system wrote: post #87
richardwhiuk wrote: post #78

Earlier quoted context omitted.

Yes, but Ofcom is, and has very similar legislation - https://www.ofcom.org.uk/spectrum/interference-enforcement/s...

The TV isn’t a jammer though, it’s a misbehaving device. Both Ofcom, the FCC, and most regulatory bodies handle intentional interference differently than accidental interference. You still aren’t supposed to operate misbehaving devices, but regulators generally realize you might not know your device is bad.

Sure.

Re: Old TV caused village broadband outages for 18 months

#288

Post by BurningFrog »

justin66 wrote: post #283
BurningFrog wrote: post #278

Earlier quoted context omitted.

My impression is that regulations turn to legacy status more often than not. Not that I've conducted any scientific study to back that up. For radio spectrum you don't need any regulations or regulators. Just establish that radio frequencies in a certain area can be owned, and use general property right rules.

It's not really my area, but I feel like the distinction you're making between "regulations" and "general property right rules" is a bit like the distinction that is made at times between "fees" and "taxes."

To me, "regulations" either means there is a regulator directly issuing rules and orders to the regulated industry, or a legislature manages the rule set through occasional legislation.

This is quite different from laws protecting property, where all the state does is settle property disputes.

In slogan form, one is "rule of man" vs "rule of law".

Re: Old TV caused village broadband outages for 18 months

#289

Post by justin66 »

BurningFrog wrote: post #288
justin66 wrote: post #283

Earlier quoted context omitted.

It's not really my area, but I feel like the distinction you're making between "regulations" and "general property right rules" is a bit like the distinction that is made at times between "fees" and "taxes."

To me, "regulations" either means there is a regulator directly issuing rules and orders to the regulated industry, or a legislature manages the rule set through occasional legislation. This is quite different from laws protecting property, where all the state does is settle property disputes. In slogan form, one is "rule of man" vs "rule of law".

I think I mentioned it upthread but principles-based regulation can at times be a nice middle ground.

Re: Old TV caused village broadband outages for 18 months

#290

Post by LargoLasskhyfv »

milankragujevic wrote: post #247
LargoLasskhyfv wrote: post #242

Earlier quoted context omitted.

By that you mean GPON, I guess? Not so here, where it is PTP. And an ISP with excellent peering.

Edit: disregard my comment, I mistook PTP to mean Ethernet while in reality it's Point to point Fiber. In any case my point about noise still stands. But PTP Fiber is really rare in the world, given how many people are stuck on coax. Yes, with FTTH (or FTTP) I meant GPON. Refarding PTP, do you mean a residential ethernet network? (Technically FTTB, copper / ethernet to the premises) Branding anything other than FTTH…

I meant a residential fiber network, where the fiber really goes into the home, and the topology of that network is point-to-point. As in from some POP(point-of-presence) from ISP into the home, not over shared channels like in GPON.

My ISP is rolling that out, though with delays. They are a spin-off of a public utility.

Already rolled out the CPE looks like this:

https://genexis.eu/product/fibertwist/

and in the user-forum of that ISP there are people describing how to directly interface to fiber with a pre-fabricated cable and SFP-transceiver with the right wavelengths, from a self-owned router with SFP-cage.

But you still have to connect over PPPoE with a MTU of 1492 bytes. Multiple times actually, on different VLANs for management, VoIP, and public dynamic IPv4(CGNAT)/IPv6(native/64)

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