In the never ending evolution of remote broadcasting equipment, Comrex has yet another way to connect to the studio with broadcast quality audio. For use with their Comrex Bric-link or ACCESS equipment, they have authorized an iPhone app called Media5. It requires a SIP account and costs $4.99 to download, which last time I checked, was pretty reasonable. I am not surprised that remote equipment manufactures have tapped into the 3G/4G wireless networks that span most of the country.
Time was when a remote required ordering an equalized phone line from Ma Bell. This usually required 2-4 weeks, depending on the local branch. Spontaneous remotes were but a pipe dream. Then came Marti with inexpensive RPU transmitters and receivers, this greatly reduced the lead time required for establishing remote broadcasts. The downside to Marti equipment is it takes at least some technical know how to set up because of all the antennas and coax and such.
Comrex came on the market with Telephone Line frequency extenders then with 3 line comrex units (3XP/3XR). A three line unit split the incoming audio into three different sections, reducing each to 300 to 3,400 Hz telco line base band. At the other end, the answering unit changed the sections back to their original frequency range, then recombined them into pretty good sounding audio from 50 to 10,000 Hz or so. I have used these units on several occasions. I believe that one of the stations I work for still has one of these in their storage unit, along with several EFTs.
Latter, Comrex came out with POTS line codecs like the Hotline, Matrix and Blue box. Now only one phone line was needed to do a remote. This greatly simplified remote availability and set up. The downside to these is it had to be straight dial tone, no PBX’s or any thing like that. A noisy line can create problems with audio quality and dropouts.
The Matrix can be used with ISDN and they used to have a GSM module to use with certain cellular networks.
The latest Comrex products include IP and VOIP capabilities. These systems are great when a broadband WIFI networks is available to be used. Unfortunately, an open WIFI with good signal strength is not always at hand. So the 3G/4G option is a natural.