Story last updated at 7:08 PM on Wednesday, March 15, 2006

New digital system for police radio scrambles signals


Hobbyists, reporters or nosy neighbors listening to radio scanners might have noticed a change on the Homer Police Department communication frequencies.

To use the police 10 codes, does it seem that the signal is 10-1 (receiving poorly)? Don’t bother to 10-3 (switch channels), because as of late February, the department has gone digital and encrypted its signal. As far as the public is concerned, open communication between cops is 10-7 (out of service).

The latest change in technology is part of a $500,000 upgrade — paid for with a Homeland Security grant — to the Homer Police communications system that started 18 months ago when the department upgraded to Project 25 — an industry standard — digital radios. With new software installed, the signal between dispatch and police officers is now digital — a change that also allows the signal to be encrypted or scrambled.

Instead of officers announcing over open airwaves that they’ve 10-23 (arrived) for a 10-81 (meal), now all citizens hear is an annoying buzz followed by what sounds like a couple of angry parrots bickering. Even without encrypting signals, the new digital transmission makes old analog scanners obsolete.

“Just going to a digital upgrade would have made it that you had to get a $2,000 system to listen,” said Homer Police Chief Mark Robl.

The digital upgrade is part of a trend in public safety communications. Nationwide, police, fire departments and other agencies have been working toward “interoperability,” or the ability to communicate across departments. In Alaska, the Department of Military and Veterans Affairs has been building the Alaska Land Mobile Radio network, a communications system to link everything from small-town police departments to the U.S. Department of Defense. Going digital for the Homer Police makes that happen easier.

“When that system comes on line, we’re there,” Robl said.

Digital radio also results in a clearer signal and is less affected by atmospheric interference from sun spots or other phenomena.

“(Digital) really enhances and improves our communications,” Robl said. “It’s basically made it crystal clear right out to the range of our coverage.”

Digital radios use a narrower radio bandwidth than analog radios and are more precise, said Craig Forrest of TechConnect. A Radio Shack dealer, TechConnect sells numerous models of scanners.

“Think of it as a set of railroad tracks,” Forrest said. “It’s narrow gauge versus standard gauge.”

While it won’t be possible for neighbors to hear who got arrested for drunk driving over the weekend, the tradeoff for police is more privacy. For example, an officer who stops a driver for a traffic violation often runs a 10-29 (warrants check) to see if someone is 10-97 (clear). Because of the risk of identity theft, private information like social security numbers — used to verify identities for people with common names — can’t be sent over public airwaves, Robl said. Police also don’t want to make other information available, like the identity of someone killed in a car wreck before next of kin have been notified.

Before digital radio scrambling, police would have to call in that information using cell phones. With encryption, any sensitive information can go out on a radio call.

“It’s really streamlined things for us from that standpoint,” Robl said.

There also had been the risk that criminals would use portable scanners to keep track of police activity, he noted.

Robl said communicating with agencies outside the police department hasn’t been a problem except with harbor officers. The harbor office can talk to the police, but can’t receive.

“It’s a little bit of a problem,” Robl said. “We’re working on it.”

Because of the high cost of digital radios, the Homer Volunteer Fire Department won’t be converting to digital equipment in the foreseeable future, said Homer Fire Chief Robert Painter. Digital mobile radios cost about $1,500 each compared to $500 for an analog radio, he said.

At the higher cost, though, digital radios don’t have a pager capability, Painter said — an important feature for HVFD’s 40 volunteer firefighters and emergency medical technicians. With a pager, firefighters and EMTs can leave their radios on mute. When dispatch sends out a pager alert — a specific radio tone — it turns on the volume to the radio. If the fire department purchased digital radios, it would also have to get pagers.

AMLR is “backward looking,” Painter said, meaning the system is designed to allow communication between digital and analog radios. Homer Police can communicate with Homer Fire by switching to analog mode, Robl said. HVFD also has two portable digital radios for command staff, Painter said.

Encryption isn’t an issue for the fire department. The only real concern would be with federal privacy laws regarding medical information. Painter said he didn’t think those laws applied to EMTs or firefighters providing patient information over the radio, as when an EMT gives vital information — heart rate, blood pressure, and so on — to a hospital employee. Encryption could get in the way when communicating with other emergency services departments, as with a request for mutual aid for a fire or accident.

The Alaska State Troopers have been adding digital radios throughout the state, and eventually will be at the same point Homer Police is now, said trooper spokesman Greg Wilkinson, “Ultimately, everybody’s going to be digital,” Wilkinson said. “Not everybody is going to be encrypted.”

As with the Homer Police, when the troopers change over to digital radio, calls will be encrypted, said Capt. Tom Bowman, head of E Detachment for the troopers. Technically, troopers could switch between public and encrypted channels, but as a practical matter, it would make sense to stay on an encrypted channel, Bowman said.

Troopers still can communicate with Homer Police, Wilkinson and Robl both said. Wilkinson didn’t know when the Anchor Point Post or other Kenai Peninsula troopers would be completely digital.

“It’s a big project,” he said. “We’re just taking it step by step.”

Michael Armstrong can be reached at