New BT broadband service to transmit across VHF

BT's Openreach plans to use the polluting technology G.fast, that transmits across the VHF spectrum as well as HF, to deliver new broadband services

Two new broadband services are being offered providing 152 Mbps and 314 Mbps. BT has chosen to deliver these by G.fast over legacy copper wires rather than adopting the modern approach of Fiber-To-The-Home (FTTH) which causes no RF pollution issues.

BT Openreach currently uses VDSL-2 which transmits across the HF spectrum up to 17.660 MHz and has caused considerable interference to radio amateurs. G.fast will dramatically increase the RF spectrum affected by transmitting all the way up to 106 MHz.

Media Report - http://www.bbc.co.uk/news/technology-42703466

2015 - G.fast broadband across HF and VHF - http://www.southgatearc.org/news/2015/november/g_fast_broadband.htm

Math Behind SSB Explained

Al Williams,  WD5GNR has published an article describing how voice is transmitted over radio waves

AM, or amplitude modulation, was the earliest way of sending voice over radio waves. That makes sense because it is easy to modulate a signal and easy to demodulate it, as well. A carbon microphone is sufficient to crudely modulate an AM signal and diode — even a piece of natural crystal — will suffice to demodulate it.

Outside of broadcast radio, most AM users migrated to single sideband or SSB. On an AM receiver that sounds like Donald Duck, but with a little work, it will sound almost as good as AM, and in many cases better.

Media Article - https://hackaday.com/2018/01/01/why-is-donald-duck-on-the-radio-math-behind-single-sideband-explained/

Battery Powered 'Smart Bags' Raise Safety Concern

Following on from the hazards caused by hover-boards, dodgy chargers and exploding mobile phones, all associated with lithium batteries and fires, a new type of travellers’ luggage known as ‘smart bags’ are starting to get attention for their built-in lithium batteries. These small but high capacity batteries are a power source for charging external devices or to provide power to the wheels of the bag.

Passengers trying to check them in as carry-on bags are warned by two Asian airlines that if they are fitted with non-removable lithium batteries, they will be banned from flights.