To The Editor:
I recently received a copy of the article regarding the conversion to narrowband for Franklin County and wanted to clear some misunderstandings regarding the mandate.
First off, a little about myself. I manage the radio frequency coordination program for AASHTO, the American Association of State Highway and Transportation Officials, which is one of four Federal Communications Commission Frequency Advisory Committees (FACs) for public safety and local governments.
In 1986 the commission designated four groups to oversee the selection of all two-way radio frequencies used by emergency responders and other state, county, city and tribal authorities. All applications for new frequency assignments must be submitted through one of the four FACs or coordinators. It is our responsibility to process their application, select radio frequencies which will cause the least harmful interference to other users and recommend these to the commission for licensing.
As to the article, there are a few points needing clarification. It states, “Narrowbanding is being mandated by the Federal Communications Commission to free up frequencies for cellphones and other consumer devices.”
This statement contains elements which are correct as well as others that are incorrect. Public safety agencies, such as those found in Franklin County, operate in portions of the radio spectrum set aside for their communications. These frequencies are not shared with any other group outside of those authorized by U.S. Code, Title 47, Section 90.20.
With the exception of certain frequencies identified in the Middle Class Tax Relief Act, they are not subject to reassignment for commercial use. The frequencies which are subject to reallocation can only be used in 14 locations across the entire United States and are not available in Franklin County.
The narrowbanding or “refarming” mandate has been around for 15 years, so it wasn’t a shock to those who had paid attention to the federal rules. The mandate requires all users operating between 150 MHz and 512 MHz to reduce the amount of occupied spectrum from a 25 kHz channel to a 12.5 kHz channel. As the radios in use cannot exceed their assigned channel bandwidth, they are designed to keep their emissions below the maximum channel assignment. For operation on a 25 kHz channel, the radios actually occupy 20 kHz of spectrum or bandwidth.
Under narrowbanding, the amount of occupied bandwidth will reduce to 11.25 kHz. Users are not required to change their assigned frequencies.
I applaud the work done by Franklin County’s interim 9-1-1 director. Mr. Zagarri is following the proper procedures in completing the requirements. The radios have been inventoried and units certified and manufactured prior to February 1996 have been identified and replacements ordered. Mr. Zagarri has a conversion date and plan where he will begin by replacing the repeaters or fixed sites which are not capable of operating with narrowed emissions. He then will, from appearances in your article, begin the reprogramming of the units in vehicles and any portable radios to reduce their channel width.
From experience, some issues that will arise during the conversion process also have been identified. The radios remaining on wide emissions will sound overly loud to those operating with narrow emissions with the reverse of narrow emission radios being “soft.” The county has also completed the step of modifying all its licenses to add narrow emissions.
The county may also experience a reduction in the range of the radios, but this normally is not an issue as it would be experienced at or near the maximum range of the older wideband units. There should be no difference in day-to-day operations once the conversion is complete.
What is important to note is what the mandate does not require. The mandate only states a licensee must reduce its emissions from a 25 kHz channel to a 12.5 kHz channel. The mandate does not require a licensee to change frequencies or migrate to digital radios. Many jurisdictions have used the mandate as justification for completely new radio systems costing many millions of dollars.