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  Information is unofficial, and Denver Radio is not affiliated in any way with the agencies listed, unless indicated.  
What happened to Aurora??

Has Aurora changed their radio system?

Yes.  They have been using an EDACS trunking system since 2004.  They were in a transition mode to a P25 Phase 2 digital trunking system for about 6 months.  There was a cross-patch from the old EDACS system to P25 until Friday, July 15, 2016.  At that time, everything was on the new P25 system, and the EDACS system was shut down.

Aurora Police are now fully encrypted, and not monitorable.

More information is available at Denver Radio's Aurora P25 change information page.

Mountain News Net
Incident reporting system
If you are monitoring your favorite area (or not monitoring at all), and something happens in another area, how do you know? If you have Mountain News Net, you'll get a text message on your cellphone or pager with all the details as they are available. You can then tune to that radio system, and hear all the action. Over 400 MNN members, including the local news media, subscribe to this great service. The cost is very low, and there are dozens of other people contributing their information. This service is used by Denver Radio, and it is essential!
  • The cost is only $30 a year for individuals (more for commercial users).

 To start your service, just e-mail Jim Richardson, and mention Denver Radio.
  • You can see the kinds of alerts you will receive at Look for the Mountain News Network screen on the right side of the page.

What the heck is this trunking, anyway?


You're not the first person to ask that question. Trunking uses a pool of frequencies that are shared by all the users, and all the different frequencies in the system are 'trunked', or shared electronically. Each channel in the system rotates through different usages, so there are no dedicated frequencies for any specific use. Trunking is used by just about all Metro Denver public safety communications systems, plus the Colorado DTRS (Digital Trunking Radio System). Boulder County is the exception; they use VHF conventional frequencies, but are slowly starting to use the DTRS (Longmont is almost completely changed to the DTRS).


See Trunking theory for a simplified explanation.


Effective July 1, 2013, Colorado law requires most electronic items to be recycled, not just thrown in the trash.


How can I recycle my old electronics for free?

Best Buy has a free recycling program, no matter where you bought it! Click on the link to get more information


The City of Denver has a discounted recycling program for Denver residents.

Why did my scanner stop receiving

Denver Police, Fire and Ambulance?

 What about Lakewood?

On 12-14-11, the Lakewood trunk system switched from EDACS analog to P25 digital. This includes West Metro Fire and Wheat Ridge. Lakewood Police are now encrypted. Frequencies and renumbered talkgroup ID's are available here.

The plan for renumbering EDACS TG's (in the decimal display mode) seems to be:

EDACS TG's with 3 digit ID's, add 37 at the beginning.

TG's with 4 digits, drop the first digit and add 37 at the beginning.

These modifications will create 5-digit TGID's for the P25 system


Lakewood Public Works is remaining on the EDACS ESK trunk system.

In August 2008, Denver implemented a restructured control channel mode on their Public Safety trunked radio system, which is used for police, fire, and ambulance. It's called ESK (EDACS Security Key). This is to make it more difficult for unauthorized persons to program a two-way trunked radio to operate on these systems. It also has the effect of shutting out many scanners from receiving the trunk systems.


The only radios which can receive an ESK trunk system (as well as non-ESK analog trunk systems) are:

  • The Uniden BCD-436HP and BCD-536HP
  •  GRE PSR-500 and PSR-600, and the Radio Shack equivalents, the PRO-106 and PRO-197 (discontinued)
  •  Radio Shack PRO-107 (discontinued) and GRE PSR-700
  •  Bearcat Uniden BC-346XT + BCT-15X non-digital scanners
  •  Bearcat Uniden BCD-396T and BCD-996T, which must have have firmware upgrades 3.xx installed to track ESK. Denver Radio can install this upgrade for you.
  •  Uniden BCD-396XT and BCD-996XT
  •  The Uniden Home Patrol 1 and 2
  •  The GRE PSR-800, and the Whistler equivalent WS-1080, plus the new Whistler base/mobile WS-1095

Other metro EDACS trunk systems which do NOT require an ESK-capable or digital scanner:

Denver Public Works trunk

Any scanner which will track an EDACS trunk will work for these systems.

See the Denver Radio Scanner Buyer's Guide for more information on different models of scanners.



What kind of scanner do I need to listen to police and fire?

That depends on the kind of radio system that's used in the area you want to monitor. Some areas can use a very basic scanner, but many will require a more advanced model.

Sometimes Radio Shack has a basic scanner model on sale at an attractive price, but it may not receive much of what you want to listen to. Don't spend your money on a radio that won't do what you want. If you do find you have bought a radio that doesn't do what you need, remember Radio Shack has a 30-day return policy.

To see what radio you will need, check Denver Radio's Scanner Buyer's Guide page.  You can also call us at 720 248-SCAN (7226).


Where can I buy a scanner?

In the Denver area: Driving Directions
Click the map to open an interactive map in a new window.

  • Ham Radio Outlet

8400 E. Iliff Ave (take Evans east of Quebec, Evans turns into Iliff at the curve), look for the radio tower on the south side.

phone 303 745-7373, website

  • Radio Shack no longer has scanners, and the two remaining stores have closed. (January 2018)

Just how do the State Patrol callsigns and areas work?


CSP callsigns consist of their troop area plus their area number in that troop (except special units). For instance, a car in Douglas County might be 1C5 (One-Charlie-Five). This tells you he is working District 1, Troop area C, and area number 5 of that troop area.


For even more detailed information on CSP callsigns, 10-codes, and other information, check RadioReference: CSP information


CSP districts changed March 1, 2013, including the elimination of District 6 (as shown above).

Check Scanner News for updates!

Also see the Denver Radio updated troop map.

Why can't I receive the State Patrol, or my favorite county, on the Colorado DTRS (Digital Trunked Radio System)?

The Colorado State DTRS has been 'rebanded'. What this means, is that ALL of the frequencies in the system were changed. This process was completed statewide in August, 2008. If you haven't reprogrammed your scanner, it won't have the new frequencies.

In addition, many of the frequencies on the 700 MHz sites were changed in July 2010. If you were relying on one or more of these sites for reception, such as in Adams County, you may have no reception, or weaker reception.

Also, reception of users on the DTRS requires careful selection of the transmitter sites that are used in your programming!

You should contact Denver Radio for the latest programming.





 Scanner RecommendationsFrequencies
 Trunking Scanner Comparison ChartRadio Reference Wiki
 Conventional/WideBand Scanner Comparison ChartNewsgroups/Forums
 Scanner ManualsDX Radio
 Scanning Quick Reference CardsReviews/Modifications
 Trunking InfoBooks/Magazines

Need a scanner manual? You can download them free at Uniden product support.

You can also call them at 1-800-297-1023, and they may be able to help you over the phone. This service is available Monday-Friday, 7am to 4pm Mountain time. Be prepared to spend a long time waiting.

 Scanner manual downloads are available free at Radio Shack product support, If you don't find it there, check the RS Index to Scanners.

Manual downloads are available free at GRE product support.



See the Scanner repair page on this site