Recently mobile data has been suggested as a method for delivering IFB to ENG talent.
Many broadcasters are familiar with mobile data (formally known as EV-DO Rev A). It is the email and internet link for BlackBerry and iPhone. I’ve used EVDO for years to provide connectivity for my laptop. It works most everywhere cell phones do. Mobile data is especially useful in avoiding the often $15 a night hotel charge for internet access sometimes demanded. Significantly, an informal survey of our ENG customers revealed that most have EVDO in their live-trucks. It provides inexpensive internet and email access for the crew.
As proponents of IFB via transport stream (a digital version of “pro channel”) the possibility of using EVDO for IFB was intriguing; so a trial seemed in order. Putting together an EVDO IFB system was simple and inexpensive. Only three items were needed; an EVDO stick, a laptop computer and a voice over internet (VoIP) module.
The preliminary test produced a “mixed bag.” On the plus side, EVDO shows value as a backup to other ways to get IFB into the field – you can never have too many backups, especially ones as inexpensive as EVDO IFB.
However, as a primary means of delivering IFB to live trucks, EVDO seems a poor choice. It is a weak alternative even to cell phones. And cell phones remain an unwise choice for IFB with their frequent drop outs and difficulty in getting a connection at major incident scenes.
Mainly, EVDO is unreliable. In areas of even moderate EVDO usage it develops problems that will drive an on-air reporter crazy. The delay (latency) can grow to more than half a second, and even worse, it varies widely from second to second. Another issue is “holes.” Because EVDO is intended for data, the carriers make no special effort to insure steady, uninterrupted transmission. A pause of a second or two in the flow of data is hardly noticeable. The same hole in IFB during a live segment could be devastating to a reporter. Finally, because EVDO is part of the cell phone infrastructure, sharing the same towers, antennas, interconnects and power, it can never be more reliable than the cellular network.
While the hardware costs for IFB EVDO are insignificant and the monthly basic charges very modest, use for more than five to ten hours a month for IFB can generate BIG overtime bills. Most EVDO contracts (Verizon and Sprint) provide 5 GB per month of data. For web surfing that is a lot of data, but for IFB audio it is less than ten hours. News operations people say that it takes one to two hours of IFB per live segment. If the 5 GB limit is exceeded, the charge can be as much as twenty-five cents per additional MB (an MB is one-thousandth of a GB or about 25 cents per 10 seconds of IFB).
There are more test results and other issues in evaluating EVDO for IFB. Modulation Sciences is preparing some more papers with those details as well as instructions on how set up your own system for doing IFB EVDO inexpensively. Check back here in a week or so for the next installment.