Saturday, October 16, 2021

NIFOG 2.0 Available

The latest version of the Department of Homeland Security National Interoperability Field Operations Guide (NIFOG) is now available for download. You can find this PDF file at this link:

The electronic version is also available at the Apple App store and Google Play for your mobile devices:



Wednesday, October 06, 2021

FEMA Frequencies In Action


Recent events in the South Florida area prompted requests from readers for information on the frequencies used by the Federal Emergency Management Agency (FEMA).


At 1:23 AM on June 24, 2021, a large section of the Champlain Towers South condominium building in Surfside, Florida, collapsed. Nearly 100 people lost their lives in the collapse. The response to the building collapse was massive, with not only Miami city agencies and Florida state agencies responding, but quite a few federal agencies sent teams of personal and equipment in. On June 25, President Biden signed an Emergency Declaration authorizing federal assistance to local and state resources.  

FEMA can show up in nearly any federal frequency band, but their primary frequencies of choice these days is in the 400 MHz federal band. All communications are likely P25 digital and encrypted. FEMA has also been observed handing out Motorola DTR710 900 MHz spread spectrum frequency hopping radios in some situations. In addition to the FEMA channels, be sure and keep a watch on the VHF and UHF interoperability frequencies found in the DHS National Interoperability Field Operations Guide, or NIFOG. Radios deployed at disaster sites will have all the NIFOG channels available for use.


Here is a listing of known FEMA radio frequencies that were probably in use in South Florida and can be used in any disaster response. The P-25 digital channels will often be used with a Network Access Code (NAC) of N421, but other NACs have been observed in some situations. All of these can be used as repeater pairs (inputs are usually +9 MHz in the UHF band), or any frequency can be simplex:


406.2625           N421     FEMA 01/02








406.8625                         National Disaster Medical System (NDMS)

407.0625           N421     FEMA 03/04

407.1250                         NDMS


407.4500           N421     FEMA 11/12



407.6625           N421     FEMA 05/06






408.8625           N421     FEMA Urban Search and Rescue (USAR) 01

409.0000           N447     FEMA NDMS

409.0500           N447     FEMA NDMS

409.0625           N421     FEMA 07/08

409.0750                         NDMS



409.2625                         USAR


409.4625           N421     FEMA 11

409.6625                         USAR


409.8625           N421     FEMA 05

410.2625                         USAR

410.3375           N447     FEMA NDMS

410.4625           N421     FEMA 09/10

410.6625                         FEMA Urban Search and Rescue (USAR)

410.8625           N421     FEMA 14
























416.4500           N421     FEMA INPUT












418.0625           N421     FEMA 08 INPUT






418.4625           N421     FEMA 11 INPUT



418.8625           N421     FEMA 05 INPUT


419.4625           N421     FEMA 02 INPUT

419.6625           N421

419.8625           N421     FEMA 14 INPUT


I will continue to update my FEMA frequency listings on the Fed Files Blog page, which can be found here:

Government Master File

For those who may have missed the discussions on Radio Reference or in the pages of The Spectrum Monitor magazine, there has been a redacted version of the Government Master File of federal radio frequencies made available on line. 


The web site Government Attic obtained the unclassified portion of the GMF and posted it on their site. The first page of the PDF file indicate that Government Attic requested the GMF copy from the Department of Commerce through a Freedom of Information Act (FOIA) request. The request was submitted on May 19 and was released on June 25, 2021. 


 Here is a link to the file if you wish to download it for yourself:


The released PDF file is 82 megabytes large and contains over 15,500 pages of text information from the GMF, although some have noticed that there are some blank and duplicate pages in this file. It is important to note that this is only a portion of the entire Government Master File, a portion that had been unclassified for release. 


Those who are in the know say that this release is only about 20 percent of the entire file. The entire GMF is quite large and is only available to persons or organizations who hold a government security clearance. Sensitive frequencies used by agencies of the Justice Department, Homeland Security, Department of State, etc., are all redacted from this document.


Despite being heavily edited, there are some interesting federal frequencies listed for various offices and agencies that you may not have known about before, so definitely check it out if you have time to look through the file. 

Since this version of the GMF extract is a PDF file, your PDF reader program should have a search function built in. I have found that to find a specific frequency, you can search for “M162.5500”, with M standing for Megahertz and K for kilohertz. You can search for city names or federal facility names or locations.


Tuesday, July 27, 2021

"New" P-25 TDMA Control Channel In Use

This is not federal or military specific, but interesting none the less. 

A recent discovery of a new type of P-25 trunking control channel has sparked some developments in the various monitoring and analysis software solutions. 

It seems that a couple of new Harris P-25, phase 2 trunked radio systems for energy companies have started using the same TDMA modulation for the control channel data as is used for the voice frequencies. Traditionally, the control channels in P-25 phase 2 trunked systems have used FDMA modulation for the control channel data. This is potentially a big change for all P-25 trunked system monitoring, although it appears to be an option for newer systems that are being built out now and is not likely to start showing up on existing public safety radio systems.

Here is the Radio Reference forum thread with more specific information on what was found: 

The Bluetail Technologies forum also seems to indicate they have added TDMA control channel support for their SDR receivers:

Sunday, July 11, 2021

GMF on Government Attic Web Site

The web site "Government Attic" has posted a PDF of some of the NTIA Government Master File (GMF). This file contains license and associated frequency information for federal agency radio frequencies.

This file appears to have been obtained via a Freedom of Information request.  I have known several people who were able to obtain this same information by filing a federal FOI request. 

Remember that this is the unclassified section of the GMF and contains no real information on federal law enforcement agencies or their radio systems. Even with that said, there are many interesting tidbits of federal frequency usage by other agencies.

Friday, April 23, 2021

Bonneville Power Administration

Back in February, I mentioned in The Spectrum Monitor column that the Bonneville Power Administration was in the process of expanding their radio network. The BPA, part of the Department of Energy, is responsible for distributing power generated by some of the hydroelectric facilities in the Pacific Northwest. The BPA operated in Oregon, Washington, Idaho and parts of California and Montana.

Here is a list of what might be in use once the project is completed:

168.2250         CA, CO, ID, MT, OR, WA

168.3250         ID, MT, OR, WA

172.5000         ID, MT, OR, WA

172.5250         ID, MT, OR, WA, WY

172.5750         CA, ID, MT, OR, WA

173.0625         Beverly, WA

173.1125         Boistfort Peak, Deer Creek, WA

173.1375         OR, WA

173.1500         ID, OR, WA

173.1625         MT, WA

173.1750         Capitol Peak, WA

173.1875         Targhee Substation, ID

173.4500         Capitol Peak, Sickler Substation, Teanaway, WA

173.4750         Blacktail Peak, MT, Central Ferry Substation, WA

173.5500         MT, OR

173.5750         Stampede Pass, WA

173.6000         Sunnyside, WA

173.6125         Mt. Hebo, Shaniko, OR

173.6375         Bald Mountain, MT

173.6500         Calx Mountain, MT, Augspurger Mountain, WA

173.7125         Beverly, WA

173.7250         Haystack Butte, WA

173.7375         Bald Mountain, MT, Cougar, West Portland, OR

173.7500         Roosevelt, Tunk Mountain, WA

173.8000         Hilltop Substation, CA, Ripplebrook, OR

173.8125         Skyrocket, WA

173.9500         Malaga, WA

173.9750         Ripplebrook, OR


406.1875         ID, OR

407.4000         ID, WA

415.1875         ID, OR

416.4000         ID, WA

Thursday, February 04, 2021

Super Bowl LV in Tampa

Just a quick note that Super Bowl LV is near at hand and I am in the middle of the broadcasting of the big game. It's going to be a little different this year with very limited crowds and social distancing within our work areas at the stadium.

We've already had the usual parade of DHS helicopters orbiting the stadium each day, as well as the Department of Energy survey helicopter looking at background radiation levels.

I will have more of what I saw and heard in March edition of The Spectrum Monitor magazine!



Department of the Interior Radio Systems


Here is a recent article addressing the woes of the Department of the Interior and their various radio systems for the various agencies within the DoI;

The article mentions an audit by the Office of the Inspector General of the DoI from 2007:

And the subsequent verification review in 2017:  

And an example of the difficulties of some of the users of the DoI radio systems:

Friday, January 22, 2021

New CBP/FBI Aircraft Call Signs?

Amongst the flurry of activity surrounding the 59th Presidential Inauguration, there were reports that some different radio call signs heard being used by some federal agencies.

Although probably not related to the Inauguration activity, a reported FBI aircraft was heard using the call sign of KONA. This was seen reported on some social media postings.

And there were several reports of Customs and Border Protection (CBP) aircraft using the call sign of TROY. The aircraft using this call were reportedly the slick, dark colored Sikorsky S-76 helicopters seen around the Washington, DC area -

While the FBI has several call signs they have been known to use, including ROSS, JENA and others, the CBP aircraft usually answer to the OMAHA call sign, but have been known to use special, mission-related calls. 

We will see what comes up in Tampa at the upcoming Super Bowl game.