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Telemedia PTY Ltd

Telemedia PTY Ltd
Telemedia was founded in 1981 with a focus on the supply, installation and service support for radio and television broadcasting equipment. Since then Telemedia has evolved into a broad-­based media broadcast facility providing a sophisticated and versatile product range.

Comrex releases new firmware version for ACCESS codecs

Comrex has released firmware version 4.5p2, a new update for its line of IP audio codecs. Firmware version 4.5p2 is being released in conjunction with ACCESS MultiRack, a new multi-instance codec from Comrex, to provide seamless integration of all functions with legacy single-instance ACCESS codecs. This new firmware simplifies CrossLock connections between the new ACCESS MultiRack and legacy Comrex IP audio codecs.

Firmware v4.5p2 also replaces an older Adobe Flash-based GUI with an HTML5 web-based GUI as the default user interface. This new interface avoids the security risks posed by Adobe Flash, and is supported by all browsers. The Adobe Flash interface can still be accessed by typing <ip address>/flash to view the Flash web GUI.

ACCESS firmware v4.5p2 is available for ACCESS Rackmount, ACCESS Portable 2USB, ACCESS NX Portable, BRIC-Link, BRIC-Link II, ACCESS MultiRack and ACCESS NX Rack.

Users can upgrade their Comrex IP audio codecs using the free Device Manager application which can be downloaded on the Comrex website. If a user is updating a device from FW version 2.7.1 or earlier, they can contact Comrex Support for assistance.

Comrex is represented by Telemedia (PTY) Ltd in South Africa.

Comrex IP Connectivity Solutions

Comrex has been active in the broadcast arena since the 1960s, and the brand is well known in South Africa for their audio products.

Previously, Comrex audio products and solutions consisted primarily of hybrids, audio connectivity units for ISDN and POTS connections and Studio Call Management Systems.

Today, broadcast technology leans more towards IP-based workflows and technologies. As such, Comrex have evolved their connectivity products, taking advantage of benefits of IP technology by either improving existing products or introducing new ones with additional IP-related features.



LiveShot: The LiveShot is an IP Video Codec and is available in portable and rackmount versions. The units use MPEG-4/h.264 video encoding that accepts Video PAL; SD/HD-SDI on BNC and HDMI connections. Video is sent in both directions including a cue (audio) channel. This is ideal when using the portable unit for live stand-up positions.

The portable unit uses two high performance 3G/LTE modems with high-gain antennas to ensure good mobile connectivity. A USB modem hub can be used to combine up to four USB modems. The portable unit can also take a USB Wi-Fi dongle and on-board Ethernet for fixed network connections.


Access: The Access system is an industry leader for Radio OB activities via 3G/LTE connections. The units can send and receive an audio feed to a rackmount unit. The unit can – using an AAC audio algorithm – change the bitrate of the audio depending on the mobile bandwidth available.

The Access 2USB and newer NX unit are designed for portable OB use – the units can connect via 2 3G/LTE modems, Wi-Fi or Ethernet connections. Both units operate off a rechargeable battery and can accept directly 2 (NX) or 1 (2 USB) microphone inputs. The units also have a bolt-on mini mixer available, so that up to five microphones/audio sources can be mixed. The Access rackmount NX version can also connect via AES67 Audio.

BRIC Link II: The BRIC LINK I/II has, for a long time, been the go-to product for moving audio between broadcast facilities or STL links over IP/internet connections. The codec options on the unit range from High Quality Full Bandwidth Audio/Uncompressed Audio, which is ideal for managed IP networks, to audio compressed as low as 18Kbs to squeeze through unmanaged, problematic networks. The BRIC unit has a host of codecs that can be tailored depending on network conditions and availability. The unit also has the ability to adjust the bitrate automatically depending on network bandwidth conditions.

Opal: The Opal is an IP Audio Gateway allowing out-of-studio guests to interact with the studio via their internet browsers. This product makes operations on the guest’s side very simple: they will be given a URL which directs their web browser to connect with the Opal unit in studio. The Opal uses the OPUS audio encoder, which is built into most web browsers, and the built-in or external microphone on their device.

VH2: The VH2 is a dual VoIP hybrid that interfaces between the telecoms world and baseband audio world into radio studios. The VH2 also offers the same functions as its predecessors: Echo Prevention, Automatic Gain Control and On-Hold functions. The unit also interfaces with a VoIP handset so that calls can be transferred back and forth.

Earshot IFB: The Earshot is a multi-IFB solution utilising VoIP connectivity. For traditional POTS line converted to SIPS protocol, the unit can accommodate 30 SIP callers or 10 Wideband callers. Users in the field can use the FieldTap on a mobile device to interact with the Earshot. The Earshot unit can accept four input feeds which callers can switch between.


Comrex has developed several IP technologies/tools to allow the easy management of connections between their devices.

Traversal Server: The Traversal Server is an online service offered by Comrex so that users have an overview of all the IP devices (video and audio) allocated to their account. The server shows the status of the units – the local IP Address, the connection status, etc. – and is useful for codecs that are used to traverse the internet, as it helps with traversing NATs when connecting between codecs.

Crosslock: Crosslock is built into most of the IP Codecs and allows the ability to bond multiple data connections on a device. The application evaluates which connection is better, based on latency, bandwidth and jitter, and will select the appropriate route. It can also function in a Redundancy mode.

HotSwap: The HotSwap application is built into Access NX and BRIC-Link II devices where Comrex Connect Modems can be used. HotSwap backs up a link (STL or otherwise) with a wireless modem. If the primary Link fails, the units will automatically start using the wireless modem to keep the connectivity between the units seamlessly and revert to the primary once it becomes available again.

For more detailed information, visit the Comrex website or call Telemedia (011 803 3353) to speak to a specialist.

Jacaranda FM and Kaya FM employ Telemedia’s VSAT offering for live outside broadcasts

Telemedia launched its VSAT product offering at Mediatech Africa 2019. Since then, the company has seen an increase in customers requiring a reliable, yet cost-effective internet over satellite link. Telemedia’s VSAT offering is tailored to each customer’s individual requirements, and can be dry-hired, or accompanied by an experienced engineer.

One of the first customers to make use of Telemedia’s VSAT system was Jacaranda FM. The radio station needed to broadcast live from the CompCare Afriski Winterfest, held at the Afriski Mountain Resort in Lesotho. While mobile phone network coverage was adequate for voice calls, it was not good enough to sustain an internet connection for long periods of time – even for small bandwidth users, such as live radio outside broadcasts.

Jacaranda FM chose to dry-hire the necessary equipment from Telemedia. The Jacaranda technician who collected the equipment from Telemedia received a quick crash-course on how to align the dish with the satellite, and how to operate the VSAT Terminal (modem).

After locating the satellite and peaking for maximum signal, the terminal locks to the Hub carrier, and receives all of its instructions from then on. The portable 1.2m flyaway uplink dish was easily set up, and provided a dedicated, uncontended 1Mb/s upload and 4Mb/s download speed. Telemedia also provides uncapped data packages, suitable for streaming applications that use a lot of data over a prolonged period of time.

Maxwell Motloung, Jacaranda FM’s IT and Technical Systems Technician, was impressed with the easy setup and terminal performance. “Telemedia’s pro-active monitoring of the system, with real-time analytical information was very re-assuring. Being out in the middle of nowhere, this satellite internet connection was our only reliable and consistent connection back to base in Midrand,” comments Motloung.

Bi-directional communication lines and playlist control were also carried over the link. The Jacaranda crew was able to check emails, do general internet browsing and, most importantly, connect their live outside broadcast with the main studio.

Kaya FM also made use of Telemedia’s VSAT system at the Jazz on the Lake Festival, which took place at Zoo Lake in Johannesburg. Kaya FM were concerned that cellphone networks would be congested, given that more than 20,000 people were due to attend the free concert. That number was exceeded, and cell phone signal was indeed a problem. The satellite internet connection provided 4Mb/s in both directions for the duration of the event.

Telemedia deloyed an SNG vehicle and engineer for the event, to provide a higher capacity VSAT link. Our Uplink vehicle also provided power for the Kaya FM OB van. Nizaam Ajouhaar, Technical Manager at Kaya FM, was extremely happy with the service, knowing that Telemedia’s IP over satellite link would handle all his connectivity needs.

Should you wish to make use of Telemedia’s VSAT links, please email info@telemedia.co.za

Telemedia links up Lesotho

Telemedia has recently completed the first phase of the radio expansion for Lesotho National Broadcasting Service (LNBS).

The LNBS requirement was to provide a downlink solution for 14 remote sites to enable them to provide 16 radio services per site. Each system had to decode the radio services from the DTT (Digital Terrestrial) satellite T2MI distribution signal, as well as provide a backup link for each of the radio services via an IP circuit. Additionally, a return channel for a radio service from each remote site back to the head end was to be made available for contributions from the regions. Until now, LNBS was not able to switch their satellite distribution signal to the T2MI modulation scheme for the DTT transmitters because they weren’t able to extract the radio services from the T2MI feed for the remote FM transmitters.

The Telemedia solution was provided using equipment from Appear Television, Wohler and Comrex.

The solution was implemented by extracting all 16 radio services from the DTT HE (head end), main and standby servers, and packaging each stereo pair to be streamed to the 14 remote sites via IP circuits (supplied by a third-party service provider).

At each remote site, the decoders use the satellite T2MI signal as a primary feed and automatically switch to the IP stream as a backup for each radio service.

The IP network supplied the backup radio services each site, return radio channels, monitoring and control of the remote encoding/decoding equipment and an additional circuit for ancillary remote monitoring applications.

An AES audio distribution and monitoring system was also supplied, which allows LNBS personnel to monitor all incoming radio feeds and split them between the DTT main and standby head ends.

This completes Phase One of the project, whereby equipment for the HE and four remote sites have been completed. Remaining sites are to be implemented as soon as their equipment housings have been completed onsite.

Additionally, a mobile workshop for the engineers servicing the remote sites was supplied. This was based on a Land Cruiser 76 series: the vehicle was modified with extra travel suspension, winch and recovery kit to enable it to reach the extreme remote sites.

The bin section was kitted out with an aluminium canopy with a movable load shelf to mount and transport transmission equipment, with an inverter generator and tools to service the kit onsite.

Internet over satellite for broadcast links


TV and radio broadcasters and production companies are continually pushing technical boundaries to allow for their creative needs. However, often outside broadcast productions find themselves well outside any fixed internet or mobile network coverage areas. In these cases, a satellite link is the only option for their contribution needs.

SNG is the most reliable mechanism for quick and temporary content delivery from anywhere to anywhere. Especially on big events, outside broadcast productions are, increasingly, demanding more facilities at their disposal. A typical OB requires bi-directional communications and a contribution circuit back to the broadcaster.

With the rise of social media, however, outside broadcast productions are now requiring internet and VoIP services at the remote location to supplement the production. This connectivity is normally provided using fixed-line operators or cellular (mobile phone) networks for audio comms and data services. In some locations these services are not easy to deliver or are not reliable, and often have a hefty price tag for a temporary service as once-off installation costs need to be paid for what would probably not take place at that location ever again or with any regularity. Having access to a reliable internet connection for emails, internet browsing and file transfers used to be a ‘nice to have’, but is now essential for OB operations. It is with this thought that Telemedia is now adding VSAT capability to our standard SNG fleet.

Not only can satellite be used to supplement data services at a remote production, it can also be used to provide the main contribution, without the use of a full SNG truck, by providing internet to the remote location. Simple data services could be utilised by radio and internet streaming contributions at affordable rates on an occasional-use basis. It can also be used to provide internet for the new and increasingly popular use of cellphone-bonded codec systems, such as LiveU.

These units make use of a combination of mobile networks, Wi-Fi networks and fixed-line Ethernet, which can now be provided by the VSAT connection. When the mobile or Wi-Fi network is no longer able to provide sufficient data throughput, the satellite internet connection takes over. The blending (or bonding) together of different connectivity methods is seamless and dynamic, as the system senses which is the best route for the data to travel over.

Most VSAT networks use a hub-spoke topology, whereby the remote terminal is received by a single “hub” system, which in turn transmits to all of the remote terminals (the “spokes”) individually. The bulk of the infrastructure cost is at the central hub site, where most of the radio frequency (RF) and network processing takes place.  The cost of a remote terminal comes in at a fraction of the cost of an SNG, making it more affordable for internet streaming and radio services.

For many productions, the use of satellite and SNG trucks is expensive. The advantage of VSAT is that it can be easily relocated and the same service can be provided at the new location, thereby providing the same service at any location. Depending on the demands of the production’s data requirements, the same service can even be shared amongst multiple venues.

At the end of the day, this ability to re-use the same service on an occasional-use basis will make satellite affordable and more reliable for the broadcaster. In the past, a very high premium was paid for a guaranteed connection, with service-level agreement (SLA) and/or quality of service (QoS) issues to be brokered. For mission-critical broadcasts to OTT platforms, the production company cannot afford a ‘best effort’ connection. Critical productions would not accept any downtime or sub-standard performance due to third-party providers that are unable to provide fault reports or real-time analysis of the OB links.

Uptime and guaranteed QoS is therefore crucial for broadcast links. It was for these reasons that Telemedia took the decision at the beginning of 2019 to invest in our own VSAT Hub to offer VSAT services to the broadcast industry. Based at our Rivonia Teleport, we have the fibre infrastructure to offer internet or dedicated network connections to customers. Telemedia chose the Newtec Dialog Platform, based on their product offerings and pricing options and international track record. As a telecommunications and broadcast industry service provider, Telemedia has the flexibility to tailor any customer requirements into an affordable solution that is guaranteed to work.

Satellites will be around for the foreseeable future, until fixed-line telco operators can offer guaranteed connectivity solutions. While this is taking place, a client’s occasional-use needs are served by satellite links, particularly covering every region of rural Africa. Telemedia’s market research has indicated that the broadcast industry is looking for a satellite-based internet connection that is reliable, easy-to-use and affordable, and operated by an experienced broadcast industry service provider that understands their needs. Telemedia’s new product offering will enable existing customers to explore new production opportunities and offer new customers, especially radio and streaming providers, an opportunity to go live anywhere, any time.

Written by Andy Louis, CTO, Telemedia (Pty) Ltd.


Telemedia partners at Mediatech 2019

Telemedia is exhibiting at Mediatech Africa 2019. The company’s solutions include the following connectivity services: fibre, satellite, VSAT, terrestrial microwave, 3G bonded devices and internet.

Additionally, Telemedia offers several products for broadcast applications, such as studios, OB vans, SNG vehicles, playout systems, MAM systems, microwave connectivity, video management and compression for satellite head ends and OTT; IP video routing solutions and much more. Whatever your broadcast needs, Telemedia will help you.

At Mediatech Africa 2019, Telemedia is hosting representatives from Nevion and Hitachi Kokusai.

Hitachi Kokusai Electric

Hitachi Kokusai Electric is a leading Japanese manufacturer of broadcast, industrial and CCTV camera systems – with cameras for all applications. Broadcasters all over the world rely on Hitachi cameras for their content and enjoy the great picture quality and solid reliability that Hitachi cameras provide.

Mark Capstick, general manager of Broadcast Solution Sales at Hitachi Kokusai Electric Europe GmbH, will be representing Hitachi at Mediatech Africa 2019. With 30 years’ experience in broadcasting, Capstick started his career as a broadcast transmitter engineer with the UK’s Independent Broadcasting Authority (IBA).

He then moved to Thames Television – holder at that time of the ITV Licence for London Weekdays – where he worked in electronic maintenance covering all studio, MCR and presentation equipment at Thames TV’s Euston Studios. He spent a large amount of his time at Thames in camera, ENG and PSC (Portable Single Camera) maintenance – gaining very valuable and detailed knowledge of studio and portable cameras. In 1992, Capstick moved to a broadcast equipment manufacturer, taking a position as broadcast engineer looking after all technical aspects of their broadcast camera and monitor business. He quickly progressed to chief engineer and then, in 2001, he became general manager of the UK Office.  He remained in that position until 2016, when Hitachi Kokusai asked him to become general manager of their Broadcast and Industrial Camera operation for the UK, Western European and Africa.


As the architects of virtualised media production, Nevion provides media network and broadcast infrastructure solutions to broadcasters, telecommunication service providers, government agencies and other industries. Increasingly based on IP, virtualisation and Cloud technology, Nevion’s solutions enable the management, transport, processing and monitoring of professional-quality video, audio and data – in real-time, reliably and securely.

From content production to distribution, Nevion solutions are used to power major sporting and live events across the globe. Some of the world’s largest media groups and telecom service providers use Nevion technology, including Arqiva, AT&T, BBC, BT, CCTV, EBU, France Télévision, Globo Grupo, NASA, NBC Universal, Sinclair Broadcast Group Inc. and Telefonica.

Nevion will be at Mediatech Africa 2019 at the booth of its South African partner, Telemedia, where the company’s flagship products will be on show: Virtuoso, the software-defined media node; and VideoIPath, the orchestration and SDN software.

Ebby John, sales director for Middle East, Africa and India, is representing Nevion at the show. John has been performing a consultative sales role at Nevion for the past 15 years, ensuring his customers understand the value Nevion can bring to their business.

Visit Telemedia (Pty) Ltd at Mediatech Africa 2019, taking place from 17 – 19 July at the Ticketpro Dome, Johannesburg.

Telemedia (Pty) Ltd at Mediatech Africa 2019

At Mediatech Africa 2019, Telemedia is showcasing a number of innovative and industry-leading products and solutions from their suppliers. Products and solutions on display include:


Hitachi manufactures a wide range of high-quality, professional broadcast cameras – with a camera for every application. Whether you are looking for studio, OB/EFP or remote / POV cameras, Hitachi has a camera to meet every technical requirement and budget.

  • SK-UHD4000

Hitachi’s top-of-the-range camera – the SK-UHD4000 – is a 4K UHD system camera with 2/3-inch CMOS sensors and a standard B4 lens mount. The Fibre CCU can output not only 4K (12G or Quad-3G) but also simultaneously outputs HDTV signals  – making it a great future-proof, multi-format,  multifunctional camera for studio or OB use.

Hitachi also has a range of 1080i/1080P(3G) switchable HD cameras, fitting all price and technical/feature categories:

SK-HD1300 with three 2/3-inch CMOS sensors and remote controlled filter wheel.

SK-HD1800 with three 2/3-inch (Global Shutter) CMOS Sensors and remote controlled filter wheel.

Z-HD5500 with three 2/3-inch (Global Shutter) CMOS Sensors with Manual filter wheel.

All these cameras can be used with a range of CCUs – offering fibre, triax or Wireless connectivity.

  • SK-HD1300-S3

The SK-HD1300-S3 is a fibre-based 3x Speed Super Slow-Motion HD camera system, providing a high quality, but cost-effective, Slo-Mo companion camera.

If 1080i format HD is all that is required, then the Z-HD6000 with three 2/3-inch CMOS Sensors and Z-HD5000 with three 2/3-inch (1 Mpixel) IT CCDs are – more budget-friendly alternatives, with lower-cost triax or fibre systems also available.

There is a range of viewfinders which are compatible with all SK and Z series cameras – including  2”, 7” and 9” LCD and 7.4” OLED viewfinders.

For remote pan/tilt systems and POV applications, Hitachi has a range of compact box cameras:

The DK-H200 (1080P – 3G), DK-H100 (1080i) and DK-Z50 (1080i with 1M Pixel CCD sensor) all have standard 2/3” B4 lens mount.

Broadcasters and production companies all over the world depend on the solid reliability of Hitachi cameras, and enjoy the natural, high-quality pictures that they produce.

Vislink Technologies

  • Vislink HCAM

The Vislink Technologies HCAM wireless camera transmitter is a highly flexible ultra-low latency, HEVC 4K UHD-capable solution that features configurable mounting options and the latest video interfaces – allowing the unit to be mounted to broadcast cameras for time-critical sporting events and entertainment programming.

The HCAM 4K Wireless Video Transmitter has recently been updated to offer improved HD operation. Now, with the updated HCAM HD HEVC technology, professionals can operate HD at lower bit rates and realise improved reception and transmission robustness.  Picture quality measurements and subjective video testing have recently demonstrated that the latest Vislink HCAM can provide equivalent quality 1080p HD video compared to the best MPEG-4 1080p HD resolution wireless camera devices, both at a significantly lower bit rate and with an equivalent latency. The HEVC compression gain and bit rate reduction that the Vislink HCAM offers is, in fact, significant enough to allow a reduction in modulation scheme from 16QAM to QPSK.

The change to the RF modulation that improved efficiency HEVC compression allows – compared to the best performing MPEG-4 HD transmission systems – provides 6dBs more robustness to the HD 1080p transmission link budget. Camera operators can utilise this increased link budget gain to ensure greater robustness of their wireless camera transmissions – ensuring less risk of picture drop-outs, reduced rigging of additional reception antenna installations or doubling of line-of-sight transmission range.

The HEVC compression gains now available in the Vislink HCAM wireless camera transmitter also benefit productions that are originated in 1080i. Despite the fact that HEVC has fewer enhancements in its toolset for interlaced formats – making compression gains in 1080i a significantly harder proposition for a HEVC codec – Vislink HCAM can now match the compression gain, latency and picture quality of the best MPEG-4 wireless camera solutions in 1080i formats, too.

The HEVC compression enhancements now available in the Vislink HCAM wireless camera transmitter allow this high-end device to be used not only in the top tier of UHD and HDR Event production, but now also as an all-round, everyday wireless camera device – providing 1080p HD feeds from twice the range that an MPEG-4 system can achieve, with the ability to match 1080i MPEG-4 systems in all respects and with the addition of encode-decode quality gain that comes from a full 10-bit 4:2:2 compression engine.

HCAM offers seamless 4K transmission capabilities for several applications including sports, broadcasting and event coverage. With highly flexible, configurable mounting options, HCAM works well with prosumer, broadcast and ENG cameras. The unit includes Wi-Fi and Bluetooth control, compatible with iOS and Android handheld devices – ensuring that event operators can rollout a wireless camera solution that supports current and future technologies and operate it with ease.

Visit Telemedia (Pty) Ltd at Mediatech Africa 2019, taking place from 17 – 19 July at the Ticketpro Dome, Johannesburg.


LiveU on Track: How Tellytrack’s Win A Dream campaign reached the nation


In the words of Wesley Lloyd – outside broadcast production manager at Tellytrack – the company wanted to “do something special” to commemorate its Win A Dream campaign, a nationwide initiative that capped off a successful 2018 for the sports betting giant.

“Win A Dream was one of last year’s biggest marketing campaigns – it ran over six weeks – and our goal was to have remote broadcasts from betting centres all over the country for every single day of the promotion. From Port Elizabeth to Cape Town, KZN and Thohoyandou in Limpopo – we wanted to get out there and broadcast stories from every corner of South Africa.”

Lloyd explains that: “In the past we’ve done satellite uplinks, but – once we started to factor in the cost of renting SNGs and MPUs for the duration of the campaign – we realised we’d be looking at a multi-million rand production budget.”

This is when Tellytrack called in the services of Telemedia, who – as Lloyd puts it – “have been great partners to us for many, many years. Our first move out of MultiChoice was to [Telemedia’s] facilities, and we’ve just grown and grown since then. We started off with one channel – we’ve now got six – and they’ve provided all the technical support along the way. We’ve got OBs and race courses all around the country, and Telemedia provides all the connectivity infrastructure for us.”

“When we travel to IBC,” Lloyd continues, “we usually spend a couple of days there with Telemedia and our other suppliers, and they introduced us to a bonded 3G broadcasting system called LiveU. Andy Louis [Director at Telemedia] demoed it for us, and – although I’ve been a bit hesitant about the technology in the past – it fit the bill for what we were looking for perfectly. So I told Andy that we have one problematic site out in Midrand, where our cellular comms are always a bit iffy – and if the unit worked out there, we’d go for it.”

After the LiveU system aced this initial test, Lloyd explains: “From there, we literally sent a cameraman out into the field with a backpack, some batteries, a LiveU unit and a camera. We did a whole live content production with this equipment, where in the past, we’ve brought in an MPU with three or four cameras, microphones, uplink – compare that to one cameraman, one presenter, one microphone, one LiveU unit. The difference is incredible, and it was as effective as a multi-camera production.”

Moreover, despite concerns about connectivity in some of the more far-flung areas visited by the campaign, Lloyd reports that: “Every single day it worked, without fail. And it worked beautifully: the picture quality was amazing, the data usage was minimal – it was a very successful first run.”

Quentin Barkhuizen, National Sales Manager at Telemedia, comments that: “The LiveU brand is the most widely-accepted in the industry at the moment. While Live Bonded Cellular Video Transmission technology is still quite new in South Africa, it’s been used extensively in the news industry in other parts of the world – especially for rapid deployment and ENG situations, because of the ease of use and the cost-saving involved.”

Both Barkhuizen and Lloyd estimate that an effective LiveU set up can be achieved at a cost of about “ten times less than that of a traditional SNG rig.”

For those enticed by what this kind of accessible broadcasting technology could offer their own content production strategies, Barkhuizen explains that: “Telemedia offers two versions of the solution: one is that we can supply the mobile units and the receivers – and then the company who rents them can handle the entire production themselves. Alternatively – what often happens with customers outside of South Africa, for example – is that they come in with a portable unit and then we have a receiver in our MCR. Because we’re a registered ISP, we have an excellent internet connection – and so we could provide connectivity to customers on our internal network through the LiveU system, should it be required.”

Lloyd concludes by outlining some future plans that Tellytrack has for the LiveU system. “The Win A Dream campaign was a first test for us. We’re now in the midst of the Cape Season, so we’ve got another two-week campaign coming up for The Met and we’re going to use it again – but this time, on an even bigger scale. We’re going to bring in three LiveU units from Telemedia, and we’re going to have a crew in Limpopo, one in Joburg, one in Cape Town, and we’re going to go for an interactive broadcast between the three centres in a live scenario. I think this is really going to show the versatility of the LiveU unit, and – again – it’s a massive cost-saving exercise for us.”

Telemedia (Pty) Ltd is an accredited LiveU equipment reseller and service provider.


Affordable connectivity for broadcast links


Written by Andy Louis, CTO, Telemedia (Pty) Ltd.

In the past, television and radio broadcasters, production companies and studios had to resort to dedicated satellite or fibre links for their contribution or distribution circuits. It was the only way to reliably delivery their content from anywhere to anywhere.

A very high premium was paid for a guaranteed connection, with Service Level Agreement (SLA) and/or Quality of Service (QoS). Point-to-point contribution satellite links were used, which inadvertently covered an entire country or continent. Satellite bandwidth was expensive and complicated transmission and reception equipment was needed. Then land-lines over copper or fibre circuits started being installed in most major towns and cities. Telecommunications companies such as Telkom, Neotel (now called Liquid Telecom), or any other Commercial (business) Network provider provided circuits, but still at high prices. A long-term lease would have to be signed, with little or no flexibility. The bandwidth charge for these links would be calculated based on distance and required uptime (SLA).

These days there are many more options available, varying in affordability and reliability. Delivery over the public (unmanaged) internet has been a reality. There have been significant advances in technology and affordability in the domestic (retail) internet connections industry. ADSL and Diginet/ISDN lines are almost a thing of the past, and are being replaced with dedicated Internet Protocol (IP) network connections, over copper or fibre lines.

In previous years domestic internet connections were running on ADSL infrastructure, only geared for high downlink speeds. A home user would have a 4Mb/s download but only 512kb/s upload. This would not be sufficient for contribution links out of the home office/studio connection.

Whilst internet access speeds are increasing, and uncapped packages becoming more common, so is their reliability. Uptime is crucial for broadcast links, especially for permanent links. Any errors along the transmission path would result in video loss and a degraded video experience at the receiver.

One method to protect a video stream whilst traversing unmanaged networks, like the internet, is using Forward Error Correction (FEC). Additional information is sent, in the form of Rows and Columns for error correction. This method works well for links where there is no ability to have a return link. In this case (similar to satellite links), FEC works to ‘fill in the blanks’ if there are errors at the receiver. There is no opportunity to re-send the video information again, due to the live nature of video streams. A disadvantage to this method is an increase in total Transport Stream (TS) bitrate, which is total Service, video & audio information bitrate. The higher the FEC used, the higher the bitrate, which might end up being counter-productive over particularly constrained networks. Examples would be wireless networks, 3G/LTE mobile networks, or networks that have a high contention ratio (over-subscribed or congested).

The next category of link systems use encoders that sense the quality of links, and adjust the encoded bitrate, to reliably deliver video over any network. Telemedia’s Comrex LiveShot has been tried and tested over the last six months. It works really well using a combination of WiFi, bonded-cellular and Ethernet links. It also works well using only two high-powered modems, using 2 Data SIM cards.


The Encoder and Decoder form a tunnel through the internet, and communicate between each other to push for the highest possible bitrate. If or when the link starts to degrade, the encoder drops the bitrate to compensate for the worsening internet link, for example drop-outs on the mobile/cellular network.

A disadvantage is that you have to use the Vendor’s internal Encoder and Decoder, which might not be ideal for certain customers. They might want to use their own Encoder or Decoder. The start and finish part of this type of Link is HD-SDI or HDMI interfaces. Another product that is well known is LiveU, which works in a similar way. It uses any available networks: GSM (3G/LTE), WiFi and Ethernet, to send.

Another option for error-free transmission over unknown networks is to use additional packaging (wrapping) and intentional latency, or delay. An example is the popular Zixi Transmission Protocol. Their proprietary technology employs continuous feedback from the receiver, back to the transmitter, allowing for error correction without having to increase the overall TS bitrate. In this case an additional 1 second or more of latency is intentional, to allow for buffering (delaying) the TS, so that it can be re-constructed without any errors.

A disadvantage to the Zixi technology is that it requires their special software on both transmit and receive ends. It is also not a globally common platform, such as the DVB specification. However it works remarkable well and has an affordable pricing structure, based on annual license fees, for the various products available. Another advantage is that their software is easy to install and run on any Windows 7/10 Professional PC. The interfaces are easy to set up and there are built-in monitoring tools that come as standard.

There are many other Vendors that provide similar robust delivery methods. Ultimately the aim for any of the available transmission protocols is to combine the cost of using this technology and using a cheaper, more affordable internet connection.


The ins and outs of mobile video links | options, pros and cons

SCREEN AFRICA EXCLUSIVE: In the past five years, there has been an influx of video transmission technologies that allow transmission direct from camera via Wi-Fi or Bonded Cellular technologies. How do these technologies differ from the traditional DVB-T/COFDM camera-back transmitter and what are their pros and cons?

Wi-Fi Video links

This technology as the name implies uses traditional Wi-Fi 802.11x technology to stream the video from the transmitter to the receiver. These links can utilise both 2.4 GHz and 5 GHz bands to establish a link between Transmit and Receive units and variable video encoding bitrate is dependent on the data bandwidth available to the receiver. The problem sometimes experienced with these links is that their performance is dependent on spectrum availability in the operational area.

For instance, if the units are deployed inside an empty stadium; the RF spectrum is free from other users, so the system is free to utilise the data channels it needs to establish a stable video stream. However, if the stadium was full of other users, the amount of frequency spectrum drops and the system will now battle to find available channels to initiate a video stream. Typically, the units will connect but the quality of the video drops due to the low bitrate it must now use to get a feed through the reduced spectrum space.


  • Cheap.
  • License-free; these links operate using the standard Wi-Fi specifications.
  • Easy to operate and setup.


  • Advertised performance is usually based on using a relatively open spectrum with minimal RF noise and interference. Difficult to predict performance if the area is to be filled with other users. In these situations, the link is restricted in performance distance.
  • Very low power. In order for these links to remain license-free, their output power needs to be very low, resulting in their use being restricted to very short distance links (less than 100m).

Bonded Cellular Video links

These links are based on using Mobile Service Providers (3G/LTE) connectivity to link the transmitter or mobile unit (usually located with the camera) via the public internet to the receiver which is usually located at a broadcaster. These links are also capable of bi-directional voice communications via the link making it ideal for Live ENG operations in the field with minimal setup. The transmitter is designed to be carried by the cameraman or connected onto the camera. The unit then has the facility to have multiple SIM cards inserted into it to give it access to the internet. The amount of SIM cards varies with manufacturer typically, most units can accommodate 4 SIM cards, but some manufacturers can use up to 16 SIM cards.

This link technology is dependent on two factors:

  1. 3G/LTE mobile connectivity in the transmitter area.
  2. Public internet connectivity to the receiver.

Both factors have been getting better in South Africa, so the operational areas for this type of system is getting better and more reliable. However, users should be aware that they have no control over mobile connectivity performance or the public, unmanaged internet, so the use of the link must be judged correctly depending on the footage being covered and amount of uptime required. Using the system for ad-hoc news feeds in mobile coverage areas that are not overly congested, or rapid deployment to disaster areas is ideal for this type of technology. Using it at a sports stadium when it is full of fans will be very difficult to get a stable, usable video feed due to the reduced availability of data bandwidth at the mobile sites situated around the stadium. There is also no guaranteed Quality of Service (QOS), and all these links rely on a ‘best effort’ data throughput. Some manufacturers offer solutions to try work around this problem by using repeaters or stronger 3G/LTE modems which allow the system to connect to mobile sites a bit further away from the immediate vicinity of the event site to gain better 3G/LTE connectivity.


  • Cheap, compared to SNG or Licensed Microwave Link costs to get the same connectivity (typically 80 per cent cheaper).
  • Once set up; one button to initialise link is possible.
  • License Free
  • Ideal for minimal equipment live camera standup with IFB.
  • Both the Transmit and Receive equipment can be fully controlled via a cloud based Web Portal.


  • Reliant on mobile operator coverage; the operator needs to have a few SIM cards of different service providers to maximise 3G/LTE connectivity.
  • Not ideal for areas where mobile sites are congested due to too many users.
  • Cellular/Mobile phone GSM technology is geared for fast download (consumption) speeds from the base station network to mobile phone. Upload speeds are often restricted and easily congested due to the network design. Fewer 3G/LTE frequencies are available for the portable transmitters to reach the base station.

DVB-T/COFDM Camera links

These links are best compared to the Wi-Fi links mentioned above. Whereas the Wi-Fi Video links are limited to the performance of typical Wi-Fi connectivity parameters, the DVB-T/COFDM link parameters are fully controlled by the user.

High Power Output transmitters.

  • Antenna Gains and propagation can be calculated and reliably used at any time and any place.
  • Modulation scheme; Guard Intervals; Error Correction and Bit-Rates, allowing for optimal link performance.
  • Receiver configuration: multiple diversity RF inputs via fibre.
  • Dedicated Frequency Band.

Being able to change all aspects of the link, the user is capable of setting up a system that is guaranteed of performance. The main technical requirement needed is the frequency spectrum. Typically, these types of links are operated in the license-free 2.4 to 2.5 GHz ISM Band; which should be available worldwide however, this is normally not the case. In certain areas, this spectrum is saturated with other users and creates problems in trying to guarantee a clean link. The operator would need to invest in equipment in a licensed RF band. This adds cost to the link operation, but a clean/stable link can be guaranteed.

An advantage of the DVB-T/COFDM links is that the receive system can be customised depending on the operational environment. Namely:

  • The receivers are multiple diversity RF inputs; typically the standard input configuration allows for two RF inputs; additional receivers can be cascaded together to create a multiple RF input system. The multiple inputs help with reception in high multi-path environments or it can be used to locate various antenna receive points in locations where the RF camera would roam, thereby eliminating blank areas.
  • RF leads from antennas to receivers can be run over fibre minimising RF loss.
  • Various antennas can be used depending on the requirement e.g. stadium or indoor environment: low gain omni antennas should be used. For long range or high RF attenuation environments (jungle/bush) – high gain parabolic or sector antennas should be used to offer increased gain in the direction of the transmitter.

A drawback of the DVB-T/COFDM system is that it doesn’t offer an adaptive modulation scheme i.e. the video bit-rate couldn’t be automatically increased if the link could reduce the Forward Error Correction and increase the modulation QAM scheme if the RF link path became better. To guarantee link performance the user will have to do a test run of the area and monitor the feed to see how well it performed and make changes if needed. The main advantage is that the performance would be guaranteed. If the operator is using a licensed frequency, no other users will interfere with the links performance.


  • Guaranteed Performance; provided licensed frequency is used.
  • Everything is flexible/customisable.


  • Expensive, both equipment and license/s required to operate this equipment
  • No adaptive modulation schemes.
  • Ideally would need to operate in a dedicated Outside Broadcast frequency band, best suited for mobile links.

Guaranteed RF spectrum availability

The main requirement for all the above-mentioned technologies is guaranteed RF spectrum availability. The link’s performance will be dictated by the following:

  • Wi-Fi: dependent on the number of users in operation, utilising similar link technologies. Bonded Cellular: dependent on mobile operator coverage and availability of data bandwidth from local mobile sites and the number of users using the same mobile site.
  • DVB-T/COFDM: link performance can be guaranteed if a licensed frequency is used.

In short, if link performance needs to be guaranteed then the operator should invest in using a licensed frequency. Using Wi-Fi or Bonded Cellular links; even though they are cheaper, their performance will be dictated by factors that cannot be controlled by the operator.

The use of these links need to be carefully weighed up against how important the link operation needs to be versus cost. Another concerning factor in the industry regarding the Wi-Fi; Bonded Cellular systems and DVB-T/COFDM in the 1.8GHz, 2.1GHz and 2.4-2.5 GHz band is the use of Screamers/Interference Sources used by Government Security Agencies at events when Heads of State/Ministers attend. These links are the worst affected because they are common off the shelf products. The use of licensed frequencies out of the commonly used bands usually help in avoiding interference from these interference devices. In fact, it is illegal for any Government Agency to interfere with a Licensed frequency user’s transmission.

Written by Quentin Barkhuizen, sales manager, Telemedia

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