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FEMA IS-951: DHS Radio Interoperability Answers

The groups of Federal Interoperability Channels designated for Incident Response (IR channels) and Law Enforcement (LE channels) include both repeater channels and simplex channels. A. TRUE


Radios contain both simplex and repeater channels, and it is important to know which are which in order to select the most appropriate channel. A. TRUE


Which group of channels is used for interoperability among all federal agencies? A. Calling or hailing channels

Incident Response (IR) channels

DHS common channels

Command and control channels

The orange button on portable radios is an active feature which is programmed the same across all agencies to send an Emergency Call transmission. A. TRUE


Which of the following options is considered a realistic best practice when planning an operation or event? A. Test radio communications in advance to ensure effective coverage

Plan operations away from challenging terrain such as hilly or mountainous regions

Avoid the need to communicate from within heavy density buildings or structures

Limit operations to areas which are more rural and away from populated urban environments

There are common DHS interoperability channels in both the Very High Frequency (VHF) and Ultra High Frequency (UHF) bands. A. TRUE


The use of encryption is required when using DHS common channels. A. TRUE


New or updated encryption keys are programmed into radios by: A. Attaching a keyloader or through over-the-air-rekeying (OTAR)

Having another user transmit the correct encryption key from their radio

Attaching a cloning cable to another user’s radio with the desired encryption key

Returning the radio to the manufacturer for an update

Handheld portable radios and vehicle mounted mobile radios both have equivalent power output and coverage range A. TRUE


The DHS common interoperability channels in the Very High Frequency (VHF) and Ultra High Frequency (UHF) bands that require access to a repeater are: A. DHSNET and DHS-RPT

VTAC11 and UTAC41



The channel FIO-1 is an example of one of the DHS common interoperability channels in the UHF frequency band. A. TRUE


Which radio function is used to change between different groups of channels programmed into the radio? A. Scan button

PTT switch

Zone selector

Accessory attachment

If “blips and bleeps” or other electronic noises are heard during a user’s radio transmission, they are most likely communicating on a digital channel, and can be expected to: A. Suddenly drop out or disappear as they move out of range

Automatically switch to analog mode

Improve audio quality due to digital reconstruction

Activate the radio’s scan mode to search for a new channel

Radios that have not yet been reprogrammed with the new common DHS template should contain the DHS common interoperability channels in other existing zones in the radio. A. TRUE


One method of changing zones on a radio begins with: A. Pressing the button, or soft key, under the menu item “Zone” on the radio display screen

Simultaneously pressing the top and bottom buttons on the side of the radio

Using the channel selector to keep moving through channels until the radio changes to the next zone

Turning the radio off and back on while pressing the home button

The primary purpose of the DHS common repeater and simplex channels is to establish interoperability among DHS components. A. TRUE


DHS radios in the Very High Frequency (VHF) band should contain which DHS common interoperability channels? A. VCALL10 and VTAC11




Where should DHS personnel using Very High Frequency (VHF) radios find the common DHS interoperability channels DHSNET or DHSTAC in their radios? A. Either in Zone IO1 or another existing zone in the radio

In Zone FCC1

In Zone FedCom1

In Zone InterGov1

To access an interoperability channel, it may be necessary for the user to: A. Activate the radio’s scan feature

Change zones on their radio

Press the home button

Attach a keyloader to the radio

When attempting to communicate on the Federal Incident Response (IR) channels during an event, the designated simplex calling channels (IR5 or IR15) should be used first. A. TRUE


If attempts to communicate on the channel designated for an event are unsuccessful, the next step should be to: A. Report to the nearest command post location

Select another channel in a different radio zone

Use the channel where you last had reliable communications

Download a new encryption key for the radio

In the absence of available repeaters, which DHS common simplex channels can be used for short range communications interoperability among DHS components? A. FEDCALL or FED-DIR