From Phil Stenholm:
Another look into the History of the Evanston Fire Department.
KSC732 IS ON THE AIR!
In June 1952, the Evanston Fire Department took a major step forward by purchasing two-way FM radios for $13,000. These radios were installed in all fire stations and most EFD vehicles. The cost was covered by funds from a 1951 bond issue. Initially, there were some issues with "bleed-over" interference from a local taxi company, but Motorola engineers quickly resolved the problem.
The use of the 20-series prefix began in 1952 to reduce confusion with other nearby fire departments that shared the same radio frequency. This helped avoid mix-ups as more departments joined the network. For example, Engine 1 became Engine 21, Truck 2 became Truck 22, and Engine 5 became Engine 25. A new pumper/rescue unit was labeled "Squad 21." Chief Henry Dorband used the call sign "F-1," which he had previously used on the police department’s frequency after getting a new radio-equipped Mercury car in 1951.
Evanston ended up sharing the same frequency with fire departments in Wilmette, Winnetka, Northfield, Glencoe, and Highland Park. Unlike the Chicago Fire Department, which used repeaters, the suburban departments didn’t have them. As a result, transmissions sometimes overlapped, causing interference.
The Evanston Police Department received the FCC call sign KSA580 in 1951, while the Fire Department got KSC732 in 1952. The base station at Station #1 was known as “KSC732 – the desk,†or just “732 – the desk.†Stations #2, #3, and #4 had call signs KSC733, KSC734, and KSC735, respectively. Fire Station #5 received KSD841 when it opened in 1955.
The radio system was tested twice daily—once at 8:00 AM and again at 8:00 PM. Each station had to confirm receipt by stating its call sign. Tests could be delayed if units were responding to calls or canceled during emergencies.
Company officers were responsible for tracking the status of other units of the same type. For instance, the officer of Engine 24 needed to know whether Engine 23 was active or not, as this could affect response areas. Officers would announce changes over the radio, often using their station’s call sign or just the last three digits.
Initially, both police and fire radio consoles were located in a second-floor room near the stairway connecting the police station to Fire Station #1. Later, they were moved to the first floor, next to the police complaint desk and away from Station #1.
Communication operators, who were civilian employees, worked under a police sergeant. Their salaries were split between the police and fire departments. Before 1975, all operators were male, often retired police or firefighters. Good memory, clear speech, and multitasking skills were essential—typing wasn’t required.
All fire calls, inhalator alerts, and details were broadcast over the EFD radio. Operators announced fires, alarms, car fires, and trash fires, while a firefighter at Station #1 handled non-emergency calls like lock-outs or odor investigations.
A four-second horn tone was sounded before each call or test. It was unique to the EFD and activated by a doorbell-like button. Once started, it couldn’t be stopped and would override any ongoing voice transmission. There were only two buttons—one in the police radio room and one at Fire Station #1’s desk.
Operators didn’t assign companies to calls. Instead, they announced the type and location twice, then gave the time and call sign. The radio system would then become a conference call. Companies due to respond would acknowledge, and the platoon commander ensured the right units were on the way.
This old-school dispatch method, dating back to 1952, remained unchanged until 1982!
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