Janesville51.1°

New scanners needed for digital switchover

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ANN MARIE AMES
June 23, 2012
— Kelsey Kenney of Beloit already has bought and tested his new digital scanners.

Other Rock County residents who like listening to emergency radio traffic at home will need new scanners by the end of the month, too.


But don’t throw away those analog scanners just yet.


Rock County emergency and law enforcement agencies so far are having a positive experience as the county’s 911/dispatch center prepares to switch to digital radio equipment from analog.


The systems were tested last week, and the results were positive, Rock County Communications Center Director Dave Sleeter said. Officials this week are reviewing the test results. By the end of the month, voice communications for all emergency responders in the county should transfer to digital radios, Sleeter said.


“The vast majority of agencies experienced good radio coverage,” Sleeter said the about the results of the digital equipment tests. “Some were reporting expanded radio coverage.”


The communications center will notify the public through local media outlets when the switch will take place. Members of the public who listen to scanners at home or in their offices will need to buy a digital scanner to hear Rock County dispatches after the switch.


Kenney was tuned in at home during last week’s testing. He is a radio buff who operates a Facebook page dedicated to Rock County emergency radio traffic. Kenney and two friends keep the page updated up to 20 hours every day, he said.


Updates can be followed at “Rock County Fire-Ems” on Facebook. The page, which focuses mostly on medical calls, is not affiliated with the Rock County Communications Center or any police or fire department in the county.


Kenny and his friends post police calls only when the incident is something visible and of public concern, such as a lost child or an armed subject, he said.


Kenney spent $437 on one digital scanner; so far, he has bought two.


“The audio was a lot better,” Kenney said of the digital transmission. “It was more simple. Clear and crisp.”


The change to digital radios is a voluntary one tied to a mandated change to narrow-band radio transmissions.


The federal government has ordered that some radio licensees reduce their bandwidth, or the width of the slice of the radio wave spectrum they use to broadcast. Systems such as Rock County’s use a 25 kilohertz slice of bandwidth, and the frequency the county uses is in the middle of the slice. The mandate requires licensees to reduce their bandwidth to 12.5 kilohertz to improve efficiency and make more room on the finite radio spectrum.


The Federal Communications Commission has said it will require a reduction to 6.25 kilohertz bandwidth, but no date has been given for that change.


Reducing bandwidth on an analog system can reduce coverage and the transmission strength by up to half, Sleeter said. That’s why Rock County decided to spend $1.9 million to make the switch to digital radios, he said.


Police, fire and emergency medical agencies in the county are spending a total of about $4 million to make the conversion.


The digital conversion isn’t universal. The Walworth County Sheriff’s Office, for example, narrow-banded its radios six months ago and reports no reduction in coverage, said Kevin Williams, captain of the sheriff’s office’s communications division.


The two counties have different analog systems, so they can’t be easily compared, Sleeter said.


One downfall of digital versus analog radio is that digital is “all or nothing,” Sleeter said.


“With analog radios, transmissions might get weaker, weaker, weaker, and still you can hear a voice,” Sleeter said. “With digital, if you get into a weak area, you hear nothing.”



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