The Educational Broadband Service (EBS) was formerly known as the Instructional Television Fixed Service (ITFS). ITFS was a band of twenty (20) microwave TV channels available to be licensed by the U.S. Federal Communications Commission (FCC) to local credit granting educational institutions. It was designed to serve as a means for educational institutions to deliver live or pre-recorded Instructional television to multiple sites within school districts and to higher education branch campuses. In recognition of the variety and quantity of video materials required to support instruction at numerous grade levels and in a range of subjects, licensees were typically granted a group of four channels. Its low capital and operating costs as compared to broadcast television, technical quality that compared favorably with broadcast television, and its multi-channel per licensees feature made ITFS an extremely cost effective vehicle for the delivery of Educational television materials.
The FCC changed the name of this service to the Educational Broadband Service (EBS) and changed the allocation so each licensee would not have four 6 MHz wide channels but instead would have one 6 MHz channel and one 15 MHz wide "channel" (three contiguous 5 MHz channels). There are currently several hundred EBS systems in operation delivering schedules of live and pre-recorded instruction.
History
Initial FCC authorization
The FCC initially authorized ITFS, in 1963, to operate using a one-way, analog, line-of-sight technology. Typical installations included up to four transmitters multiplexed through a single broadcast antenna with directional receive antennas at each receive site. Receive site installations included equipment to down convert the microwave channels for viewing on standard television receivers. In typical installations, the down converted ITFS signals were distributed to classrooms over multi-channel closed-circuit television systems.
FCC allows leasing
In the late 1970s the FCC recognized that many ITFS licensees lacked the technical expertise and/or the financial means to make more effective use of ITFS. Subsequently, the FCC authorized ITFS licensees to lease a portion of their spectrum, designated as “Excess Capacity," for commercial use, meaning ITFS licensees were required to retain forty hours per week per channel for daytime instruction with the excess nighttime hours available for commercial use in exchange for technical and financial support for their instructional service.
So, primarily in large markets, subscription premium television such as HBO, Showtime, The Movie Channel and others could be transmitted over these same microwave stations beginning at 4 PM when school was out, and continuing throughout the evening, sometimes until the wee hours. In those days, pay-TV did not broadcast during the day, so there was no interference between one type of television programming and the next.
Only after ITFS had migrated to other formats did the daytime hours of the service become available to subscription television providers which filled the hours with programming such as the five-hour-long children's show Pinwheel airing weekday mornings on Nickelodeon or long blocks of international cartoons for which the rights thereto remained in the pennies per subscriber throughout the run of the technology.
Subsequent development
Using ITFS excess capacity and up to thirteen channels in the companion commercial service, the Multichannel Multipoint Distribution Service (MMDS), a number of telecommunications companies built wireless cable systems. The number of available channels, however, proved to be insufficient to compete effectively with the expanding channel capacity of cable TV.
ITFS and MMDS licensees then sought FCC authorization to employ digital compression technology, which would substantively increase the number of program streams that could be carried on the channels of the combined ITFS and MMDS spectrum.