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That fact that this delivers 3.5 MBit/s really makes you wonder how many low speed connections out in the wild are literally broken cables that still have some amount of coupling somewhere.
10km of fiber (with transcievers made for that kind of fiber and distance)... gigabits without any issues.
10km of copper pairs for *dsl? Good luck.
To give it a fair shot, assume the driver and microphone are studio quality rather than the kind you’d find on a 1970s telephone handset. I bet it’d work pretty well.
But the real question would then be: how much of an air gap could you create and still get a connection?
Could you post to HN on an ADSL signal that’s being screamed across the length of the room you’re sitting in?
Can ADSL survive an acoustic coupler? To give it a fair shot, assume the driver and microphone are studio quality rather than the kind you’d find on a 1970s telephone handset. I bet it’d work pretty well. But the real question would then be: how much of an air gap could you create and still get a connection? Could you post to HN on an ADSL signal that’s being screamed across the length of the room you’re sitting in?
Earlier quoted context omitted.
Essentially you need loose electrons to conduct.
That's not exactly correct. Electrons don't flow through wires - there's a one-way flow of the ambient electrons around the wire from the field created. See here: https://www.youtube.com/watch?v=bHIhgxav9LY
That fact that this delivers 3.5 MBit/s really makes you wonder how many low speed connections out in the wild are literally broken cables that still have some amount of coupling somewhere.
Still amazing that it worked at all.
That fact that this delivers 3.5 MBit/s really makes you wonder how many low speed connections out in the wild are literally broken cables that still have some amount of coupling somewhere.
I had a bonded DSL line for a while when I lived in the Bay Area with service coming from two different twisted pair lines. One line was consistently ~18Mbps, the other barely 3-5. It was pretty clear that one of the pairs was good and the other was broken somewhere alone the way. The lines were all in a bundle, with no way to discern what was what any individual strand was in the bundle (or which was broken or short…
Some modems have special debug modes in that can do this too - then you get to know exactly how many meters along the wire the break is. When you get close, you can hook a resistor to the line and rerun the test and it'll tell you how many meters forward or back you need to go to find the issue.
Pretty easy to track issues down that way.
3.5Mbit!? Says a lot about my parents paltry 1Mbit. Perhaps their line was low on sodium.
The cable analyzer is showing about 55db of loss across 2 meters. That's about equivalent to the loss across 4km of "good" copper.
Most HDMI and Coaxial cables are little more than wet string https://ec.europa.eu/docsroom/documents/46433 >only 10% of the HDMI RMCD met an acceptable EMC quality of at least 50 dB coupling attenuation
Earlier quoted context omitted.
I think this is common in places where they don't expect moisture to reach, but then things change and it gets there anyway. If your POTS lines are down and the telecom company is telling you a "wet pulp repair" is underway, your phones are going to be down for a while because a bunch of paper-insulated cables need to be manually rewired because they got wet and corroded. I found this interesting: http://etler.com/do…
I know there are some telecom folks on here that may be provoked to correct me but pulp was standard before the advent of cheap plastic insulation in the 1950s on up. I live in the midwest and my brother is a lineman for AT&T. There is an astonishing amount of pulp-insulated phone line still in service today. In order to keep it dry, the conduit that the pulp lines are run through is pressurized to 5-10psi. Anyone th…
Aka Cunningham’s law
> Any kind of outage on the compressor or dryer
I’m confused: isn’t a bigger concern any physical damage to the conduit anywhere in the run that is too large for the compressor to overcome? Or are we talking football-field-sized compressors here?