TV-BAY Issue 79 July 13

To view this page ensure that Adobe Flash Player version 11.1.0 or greater is installed.

How has compliance monitoring changed over the years? The test and measurement business has actually changed quite radically over the past 25 years. The days of engineers in white coats measuring diff phase & gain on composite video signals have largely gone: nowadays, in an all-digital transmission system, the primary requirement for signal delivery is one of “monitoring” rather than “measurement” of signals. For this reason, a lot of the work we do at OmniTek is integration of our waveform and monitoring software into third-party equipment such as flat-panel displays, editing systems, switchers etc. For many applications, all that is required is a green light / red light indication that the signal on an SDI cable is within the accepted SMPTE (or other) standards. OmniTek provides both the monitoring systems and the key processing software that enables third parties to offer monitoring functions in a wide variety of different systems. Changes in technology and government measures such as the CALM Act in the US to limit differences in loudness between programmes and adverts have also led to changes in the range W CTS NE DU R P O of analyses we offer. The use of digital rather than analogue transmission has also introduced the need for eye diagrams and jitter displays as part of the monitoring package. Has monitoring Loudness presented any special challenges? OmniTek provides a comprehensive set of measures of audio amplitude on all its products – from PPMs mimicking industry-standard metering systems, through True Peak displays, to a range of displays showing Momentary Loudness (calculated over 400ms), Short-Term Loudness (calculated over 3s) and Integrated Loudness (calculated over the whole of a programme). The primary challenge has been keeping pace with all the industry standards, which have been a bit of a moving target over the past 5 years! Happily OmniTek’s software-based system architecture has meant that we have been able to keep pace with all the changes, and be first-to-market when a new specification emerges. What problems are helped by precise measurement of eye patterns and digital jitter? The key factor here is Quality of Service. How can a broadcaster guarantee that his signals are being distributed throughout his installation without introducing errors? The answer is to monitor the signal integrity at as many places as possible, and make sure that the SDI signals are well within specifications for amplitude, rise/fall time, and jitter. Eye diagrams can be generated on an oscilloscope but at a cost, particularly for 3G video where a suitable oscilloscope could easily cost £10,000. By incorporating eye pattern and jitter facilities in a waveform monitor such as OmniTek’s OTM 1000, the broadcaster gets accurate, easy-to-read displays and instant analysis which can moreover be recorded for subsequent analysis. OmniTek is an innovative test and measurement company formed in 2001, specialising in the development of video analysis equipment for SD, HD, 3G and digital cinema applications. Compact V-Lok Radio Mic Holders for Sony F5 & F55 VL-RM7 • 15-Pin Connector • 2 x Power-Con (D-Tap) 12V regulated outputs • 1 x Hirose Output VL-RM8 • 25-Pin Connector • 2 x Power-Con (D-Tap) • 12V regulated outputs • 1 x Hirose Output versatile power outputs compact design rugged construction Tel: +44 (0)1233 638715 | Fax: +44 (0)1233 638747 | Email: TV-BAY MAGAZINE: ISSUE 79 JULY 2013 | 55 TV-BAY079JUL13.indd 55 09/07/2013 16:51