05-07-2017, 09:58 AM
(This post was last modified: 05-07-2017, 10:01 AM by ppppenguin.)
It's certain that BBC and GPO worked closely to provide the necessary links. Renting a vision circuit to send audio must have been expensive unless there was a special deal, or multiple PCM signals were multiplexed into a video channel. Although multiple PCM audio signals will readily fit on a vision circuit there has to be some form of channel coding. Even if this is as simple as pulse shaping.
By 1978 it's clear that PCM distribution was well established: http://downloads.bbc.co.uk/rd/pubs/reports/1978-26.pdf
PCM was being considered in 1968, including sound in syncs: http://downloads.bbc.co.uk/rd/pubs/archi...aph_75.pdf
This report from 1970 shows it was possible to carry multiple stereo PCM audio signals over a single video link: http://downloads.bbc.co.uk/rd/pubs/reports/1970-34.pdf
This page has a lot of useful info: http://www.bbceng.info/Technical%20Revie...ts-fm.html
By 1978 it's clear that PCM distribution was well established: http://downloads.bbc.co.uk/rd/pubs/reports/1978-26.pdf
PCM was being considered in 1968, including sound in syncs: http://downloads.bbc.co.uk/rd/pubs/archi...aph_75.pdf
This report from 1970 shows it was possible to carry multiple stereo PCM audio signals over a single video link: http://downloads.bbc.co.uk/rd/pubs/reports/1970-34.pdf
This page has a lot of useful info: http://www.bbceng.info/Technical%20Revie...ts-fm.html
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
