Joe Zeff: > Indeed. At one point, I was doing senior tech support for an > ISP. One day I got a call from a customer who was having connection > issues with his ADSL, and the description made it sound like line > noise. After asking some questions, I learned that the cable from > the phone socket to the modem was too long and he'd coiled it up. I > explained that this just made an electromagnet out of the line and it > was causing interference with itself. I told him to get a shorter > cable, and not let it get coiled again. AFAICT, problem solved. If they used twisted pair in the phone cables inside your house, and the phones and modem equipment you plug into it, instead of just parallel wires, it'd eliminate a lot of interference problems. I got rid of an awful hum and buzz, in mine, by doing that. And I used to have a portable USB hard drive that would kill off my ADSL. It had an el-cheapo switchmode power supply that radiated so much crap that it didn't matter where it was plugged in (inside any room in the house), it'd instantly kill the ADSL, and it'd never recover until the hard drive was unplugged. It didn't have to be connected to anything related to the modem to wreak it's havoc. I could plug in an isolated computer (just the mains plug into the wall socket), and connect the hard drive to that computer, and that would do the damage. Didn't even have to turn the computer on. You can get similarly annoying mains hash from household lighting dimmers. And just about every appliance has a switch mode power supply, these days. -- [tim@localhost ~]$ uname -rsvp Linux 4.12.14-300.fc26.x86_64 #1 SMP Wed Sep 20 16:28:07 UTC 2017 x86_64 Boilerplate: All mail to my mailbox is automatically deleted. There is no point trying to privately email me, I only get to see the messages posted to the mailing list. It seems the modern trend with Linux programmers is to change existing software so that it's more annoying to use (e.g. making reboots required, when they never used to be), then denying that *that* is a nuisance, then saying it's necessary (ignoring that several years of prior versions didn't have that stupid requirement), then complaining about being criticised for making things worse. Don't try giving me an Emperor's New Clothes routine, it won't wash. _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx
