By CHELSEA DAVIS
Courier staff writer
---- — OTTUMWA — As local law enforcement agencies begin the switch from analog to digital communication, some police scanners will become somewhat obsolete.
The Ottumwa Police Department and Wapello County Sheriff's Office need to switch to digital frequencies in order to better communicate with each other, but that means the scanners found in many Ottumwans' homes will no longer be able to pick up on local scanner traffic.
But Wapello County Emergency Management coordinator Josh Stevens said analog-only scanners will still work with other agencies in the county.
"For an agency to move from analog to digital, they have to replace all of their equipment," Stevens said. "[Digital] P25 makes it so that in the future, they're inter-operable between different platforms of communication, which is a big push, especially after 9/11."
P25, or Project 25, "is the standard for the design and manufacture of inter-operable digital two-way wireless communications products," according to the Project 25 Technology Interest Group's website.
This ensures that no matter the brand of equipment, both can be programmed to communicate with each other, Stevens said.
"No matter what equipment they buy, they'll be able to talk to someone else if they're P25," he said.
The two departments' decisions to switch to P25 were not made to block the public from listening to scanner traffic, he said.
"It's just a new type of communication," he said. "Digital P25, from our propagation study, showed to have increased coverage, which was one of the main things we focused on when moving the equipment. That's why we did studies on various locations in the county and Ottumwa for the new tower site. We wanted to make sure that our push was to increase coverage for our first responders, and P25 showed on the studies to give us better coverage."
Police scanners that can handle P25 digital decoding cost upwards of $300 and as much as $700.
With the installation of the new communications tower on Ottumwa Street, 14 agencies will be secured to the tower with 18 attachments.
While 12 of the agencies are moving their communications equipment from atop St. Joseph Hospital to the new tower, they will remain analog as they are today, he said.
"We needed a new location because St. Joe's Hospital is going to be torn down, so it made sense for us to group some of those agencies together and pick a spot that's great for everyone, that will have back-up power at one location so we don't have multiple generators," he said.
The agencies that will soon be connected to the new tower include the OPD, Wapello County Sheriff's Office, ORMICS, Wapello County secondary roads, Ottumwa Fire Department, county fire (which pages Blakesburg and Agency Fire Departments), Wapello County engineer's office, amateur radio (part of the county's contingency plan for communications), Eldon Fire Department, a medical link toward Eldon, communications with the Iowa State Patrol and mutual aid and a microwave link.
The microwave link will connect dispatch to the tower.
"Right now we use ... phone lines that don't have a dial tone but have a continuing monthly cost, kind of like buying a land line for a telephone, but this is very expensive and has multiple sets all consolidated into a microwave link," he said.
The tower will also hold back-up attachments unassigned to a specific agency. If something were to happen to another agency's equipment, they could switch to the back-up attachments.
— To follow reporter Chelsea Davis on Twitter, head to @ChelseaLeeDavis.