New products from BAL Broadcast

BAL Broadcast has developed a series of products for carrying serial data and GPI control circuits embedded in an SDI video signal.
The one constant in TV is that the picture will always pass, so the BAL data inserters and extractors put data right in with the picture.
The data does not have to be picture related, but early applications have included sports team line-ups and match data sent back to the broadcast centre from remote sites together with the pictures. Another application has been the transmission of camera positional data with picture to allow overlaying of ‘virtual’ picture elements. In this application picture-to-data timing is important and an inserter model is available with video frame delays to handle potential timing differences.
Data insertion in VBI ensures that a clean picture is always maintained so that channel specific branding and logos can be inserted as needed. This system is regularly used over MPEG-2 compressed satellite links. Data can be received as RS232 or RS422 at up to 14,400 bps, and output at 19,200bps.
The savings in time and cost of setting up separate data circuits is considerable.
The data insertion format does not affect any embedded audio which may be present in the SDI and the user may select which VBI lines are used to carry the data, so that VITC or teletext may still be carried. The data inserters and extractors provide two SDI outputs, and an hf bypass relay ensures that a through circuit is maintained in case of power failure.
(GB)