The Federal Communications Commission (FCC) has always used a standardized method of assigning callsigns to licensees, although that procedure has changed over time. It's interesting to follow the progression of how callsigns were and now are assigned, as it often provides a method of "dating" the original license application with the FCC!

In the early days of the FCC (founded in 1934, by the way), public safety radio users operated just above the AM broadcast band and used four letter callsigns (KCOE, WPCJ, etc.) just like broadcast stations did. Back in those days, it was not unusual to hear police broadcasts all across the country, although most transmissions were one-way messages from the base station to the cars on patrol. Law Enforcement was about the only public safety service to utilize radios, as most urban Fire Departments relied on hard-wired street corner "Gamewell" fire alarm systems. Funeral home ambulances had no need to communicate with the hospital or any central dispatch point given that medical care was non-existant and the only service offered was transportation on a bed!

In the early 1930s, the electronic geniuses at General Electric and the Galvin Manufacturing Corporation (now known as Motorola) began experimenting with 'ultra-high frequencies all the way up to 112 mc.' Their work would also switch the mode of operation from AM to a static-free FM mode which became almost universally adopted above 30 MHz by the early 1950s. There was a transition period where police would listen to the dispatcher on a 1800-2100 kc. AM frequency and reply using a (transmit only) 31 MHz FM mobile!

By the mid 1950s, the VHF Low (30-50 MHz) and VHF High (150-174 MHz) bands were starting to fill, including licenses for fire departments, taxicabs, business users, construction companies, and more. UHF frequencies (450-470 MHz) were available, but the equipment was electronically primitive, more expensive to purchase and maintain, and offered less range and reliability at the time.

In the early 1960s, the FCC mandated "narrow banding" for existing radio equipment, creating new channels in between existing frequencies in an attempt to alleviate congestion and overcrowding in metropolitan areas. This led to a wholesale replacement of a LOT of radio equipment across the country, with most of the old stuff snapped up by Amateur Radio operators who could still use the older equipment on their frequencies. Many of our original 2 Meter, 6 Meter, and 10 Meter FM Amateur Radio repeater networks came from those rock-solid, reliable Motorola, GE, and RCA hand-me-downs!

The 1970s saw an explosion of activity in Fire and Emergency Medical Service radio systems, including hospital networks, paging systems, telemetry, and other ancillary devices. Law Enforcement's crutch on radio use also exploded with almost every state computerizing their driver's license records and tapping into the FBI's National Crime Information Computer, commonly referred to as "NCIC".

Businesses, school buses, lifeguards, disaster relief organizations, delivery services, taxicabs, fuel oil delivery trucks, the plumber -- you name it, a lot of commercial operators were hooking up with two way radio dispatching in these pre-cellphone days. UHF systems came into their own in the early 70s, and many technological advances in equipment and antenna design made those frequencies the band of choice in urban environments. UHF was so popular in some areas that TV channels 14-20 were reserved in certain areas (namely along the Canadian border and in the Northeast) for public safety and business use. This became the UHF-T (for "Television") band.

Increasing needs for more frequencies and the ability to send digital data through a radio signal led to development of the 800 MHz, then later the 900 MHz band. Great swaths of frequencies were simply divided into groups of Public Safety, Business, and Cellular Phone users. As frequency congestion continued, the FCC "refarmed" the UHF Television band, first removing Channels 70 through 83, then later taking Channels 60 through 69 and giving it to a mixture of Land Mobile (public safety, business users, etc.) and Common Carrier (cellphones, pagers, etc.) licensees. At the same time, VHF High Band and UHF were "refarmed" and "narrow banded", erasing licensing borders between police, fire, EMS, and other public safety users and between various business user groups, and creating new channels in between existing assignments to (once again) alleviate congestion.

And that's where we are right now!

Back in the AM radio band days, I mentioned the original Police base stations used a four letter callsign like a traditional broadcast station would now use. In the early to mid 1940s, the FCC switched to a new callsign system for VHF and UHF radio systems:

Base stations, and base stations that had all mobiles operating under one license would receive a callsign beginning with K, then two other letters, then three numbers. The number sequence would start at 200 and end at 999. Example: KKD-239

Mobile stations that operated independently (without any base station, such as traffic flaggers at a county fair) or mobile stations that regularly communicated with more than one base station received a callsign beginning with K, then one other letter, then a four digit number. The number sequence began at 2000 and ended at 9999. Example: KA-5751

Repeater radio control points and fixed, point-to-point communication posts received a callsign beginning with W, then two letters (the first from A to M), then three numbers. The number sequence began at 200 and ended at 999. Example: WAH-814

Believe it or not, the FCC also briefly tried to institute a Geographical Assignment Plan, with the second letter of all base station callsigns tied to the state where the transmitter was located. I don't have all the original details, but I do know that Ohio and West Virginia shared "KQ" and Kentucky had "KI". If you look at the older State callsigns (check the low band channels first), you'll still see a lot of these in use.

RCA RADIO AND FEDERAL INTERCEPTOR SIREN IN A 1969 DODGE POLARA

As radio usage continued to soar, this effective but quaint licensing system was eventually overwhelmed. First, the K calls were exhausted for base stations. The FCC switched to W callsigns, but since the Fixed and Marine Radio services already occupied the WA-WM block, the FCC started at WZZ-999 and started assigning callsigns backwards until ... they also ran out of Mobile K calls!

The FCC apparently re-tooled their callsign apparatus, and started assigning mobile callsigns beginning with K and one other letter, then five numbers. Example: KA-81526.

The base station callsign database briefly switched to four letters, three numbers beginning with KN, then two letters, then three numbers. Example: KNGX-762

Some really crazy stuff was happening now. The FCC was allowing - even recommending - that users with multiple licenses consolidate everything (up to six fixed transmitters and an unlimited number of mobile frequencies) under a single callsign, and allowing ther user to choose that callsign. Licensees with "mobile only" callsigns were requesting a base station be added to their license, and the license was approved with the 'two letter/four number mobile' call still attached. Obviously, a serious overhaul of the whole system was sorely needed.

Enter Sequential Licensing. Sequential Licensing erased all the boundaries on what type of licensee got what callsign. Sequential used a four letter, three number arrangement, beginning with WN. The number sequence is the same; it starts at 200 and ends at 999. Example: WNWC-903. Once the WN prefix was used up, WP was next, since WO could be interpreted as "W Zero". We are now at WQ, and I will assume that WR will follow. Everyone from public safety to business to common carrier to GMRS gets the next available callsign, whether you're a bigger system with five base station tower sites and 250 mobiles, or a small farm with a couple of 5 watt portable radios.

In a way, it's much simpler and it's understandable why the FCC abandoned the once rational and methodical callsign assignment plan. But, as a seat-of-the-pants radio historian, I also miss the ability to "know what I'm hearing" when a callsign is given. The sequential calls are generic. It's neat to look at some of the older licensees -- those with the traditional 3X3 K calls, especially if you find a "KQ" in there ...

Rick Callebs
Copyright © 2008

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