The AN/PRC 148 Multiband Inter/Intra Team Radio (MBITR) is the most widely fielded handheld multiband, tactical software-defined radio in use with NATO forces around the world. The handheld MBITR is used to support the communications of a platoon, squad or team tactical environment for secure communications. It enables small unit leaders to adequately control the activities of subordinate elements.
- 1 Specifications
- 2 Operation
- 2.1 Radio Interface
- 2.2 MBITR Channels and Groups
- 2.3 Display Menus
- 2.4 Programming Menu
- 3 Reference & Links
|Frequency Range||30 to 512 MHz|
|Output Power||100 - 5000mW (.1W - 5W) (5 W default)|
|Antenna||14 inch UHF (N/I) / 1.2 meter VHF|
|Default Frequency||36.625 MHz (Channel 1)|
|Frequency Spacing||5 or 6.25 kHz depending on mode. Channel bandwidth can be 25, 12.5, or 5 kHz depending on mode.|
|Range||Up to 10+ kilometers, depending on output power, frequency and line of sight.|
The Radio Interface is opened using the ACRE 2 Open Radio Interface key (default ALT + CTRL + CAPSLOCK). On the top are the two knob switches. Below the 80x32 LCD is the primary keypad.
ON/OFF and Volume Switch
Channel Selector Switch
- [▼] and [▲]
MBITR Channels and Groups
The MBITR has a total of 100 programmable channels. Each channel may be programmed for a different frequency (for both receive and transmit) as well as other communications parameters. Each channel is identified by a 7 character alphanumeric label or by its default channel number (00 to 99) if no label has been programmed.
The MBITR programmed channels can be assigned to groups of up to 16 channels each (to correspond to the 16 positions on the Channel Select rotary switch). When a channel is assigned to a group, it is “mapped” to a Channel Select switch position. Channels can be assigned to more than one group. If a channel is NOT assigned to any group, the radio cannot operate on that channel. The radio can store up to ten (10) groups of channels. These groups may be assigned names of up to 3 characters. The user may select only ONE Group at any given time for MBITR operations. This Group will be referred to as the MBITR’s “SELECTED GROUP.” When compiling a list of channels to a group, channels are assigned by their default channel numbers.
The MBITR in ACRE 2 features the same Display Menu found in the actual MBITR, although not all functionality is implemented. When the radio is first powered up, it performs a Power-On Self-Test (POST) and displays "TESTING". When POST is completed, the display shows “IDI-SYSTEMS” and the software version, then the display is automatically replaced by the default standby display screen.
The display includes a battery “fuel gauge” indicator, the group label for the selected group, the selected channel label, the channel modulation type (AM, FM (by default), NB, or PSK), and the security mode PlainText (PT) (by default) or CipherText (CT), as well as the "External Audio enabled" icon.
Alternate Default Display
When the Default Display is open, the user can switch to the Alternate Default Display by pressing [ENT]. The Alternate Default Display for Basic channels shows the receive frequency (RX), transmit frequency (TX), Recieve CTCSS Tone (R), Transmit CTCSS Tone (T), Operating Mode (FM by default), the Traffic Rate (16K by default) as well as the current COMSEC Key (TEK 1 by default). Press [ENT] or [ESC] to return to the default display.
The Function screens (Mode Select and Group Select) are actually a subset of the Operations screens and are displayed in response to MBITR front panel switch operations. They present the operator with a small menu of options to select using the [▼] and [▲] keys. These selections must then be confirmed with an additional press of the [ENT] key. These Function changes are made with the MBITR online and immediately affect the way the MBITR is operating, e.g., Clear mode to Secure mode changes. They are also single level menu operations that require a minimum of switch operations to complete.
To select the MBITR Operating Mode, press the [MODE] key on the front panel keypad. The menu of available parameters appears on the display. To move the selection outline, use the [▼] or [▲]. To change the selected parameter, press [ENT] to enable the change mode (the selection will be shown in reverse video (white on black)) and use the [▼] or [▲] to toggle the selection value. Press [ENT] to confirm the change and move the outline to the next line.The first line selects the audio path: internal audio, external audio, or external audio with sidetones enabled (INT/EXT AUDIO, SIDETONE). The INT AUDIO setting will enable the internal speakers of the radio, all other settings currently will utilize the external headset. The SIDETONE functionality is currently not implemented. None of the other MODE Select options, such as Emergency Beacon, are currently implemented.
Press the [GR] key to open the GROUP Select menu. This menu displays the label of the currently selected group. To select a new group, press the [▼] or [▲] keys. When the outline is on the desired group, press [ENT] to select the new group and return to the default screen.
The Programming screens are available through a menu structure and do not require user access during normal MBITR operations.
The Main Programming Menu screen is accessed by pressing [ALT] and [MODE].
To select a sub-menu of the Programming Menu use the [▼] or [▲] keys and press [ENT] to select the desired menu. Currently the only implemented Sub-Menu is the "Program" menu, all other will return "ACCESS DENIED".
The Program Menu also program a variety of radio functions. Currently only the "CHANNEL" sub-menu is implemented, which can be selected through the [▼] or [▲] and [ENT].
The "Channel" Menu allows the user to program the general channel values (channel number, encryption mode, channel label, and output (TX RF) power) and select the operating mode (the type of radio operation to be programmed in a channel). The screen opens with the Channel Number outlined. To change the channel use the Channel Knob. The various settings are selected with the [▼] or [▲] keys and [ENT].
To change the encryption mode setting use the [▼] or [▲] keys to toggle between PLAIN and SECURE, press [ENT] to confirm.
The Channel Label setting "CHAN" allows to give the Channel a custom label. When entering the Channel Label setting the rightmost character will be in reverse video. To select a new character, scroll up or down using the [▼] or [▲] keys through the 36 alphanumeric characters. When the desired character is displayed, press [ALT] and [▲] to move the highlighting to the next character. Use [ALT] and [▲] to go to the last character. When all the characters of the new label have been selected, press [ENT] to confirm.
The Output Power setting "PWE" allows to choose the desired Output Power (currently 0.1 Watts, 0.5 W, 1.0 W, 3.0 W or 5.0 W). When the Output Power setting is entered the current outpower will show in reverse video. Use the [▼] or [▲] keys to scroll through the available power settings. Press [ENT] to confirm.
The Operating Mode setting is currently not implemented.
Basic Channel Programming Options
The Basic Channel Programming Options are below the Operating Mode setting in the Program Channel menu and are reached with the [▼] key.
The Basic Channel Programming Screen opens with the RX (receive) frequency outlined.
RX - Receive Frequency
The Receive Frequency is the frequency the radio will receive on, in the current Channel. To change the frequency, press [ENT] to highlight the rightmost significant digit of the frequency with reverse video. To change the units digit, scroll up or down using the [▼] or [▲] keys. To change the first digit of the frequency, press [ALT] and [▼] to move the reverse video highlighting and then scroll up or down using the [▼] or [▲] keys. Change the remaining digits of the frequency by pressing [ALT] and [▼] and then scrolling up or down using the [▼] or [▲] keys. Note that the TX frequency changes as the RX frequency is changed.
TX - Transmit Frequency
The Transmit Frequency is the frequency the radio will transmit on, in the current Channel. To change the frequency, press [ENT] to highlight the rightmost significant digit of the frequency with reverse video. To change the units digit, scroll up or down using the [▼] or [▲] keys. To change the first digit of the frequency, press [ALT] and [▼] to move the reverse video highlighting and then scroll up or down using the [▼] or [▲] keys. Change the remaining digits of the frequency by pressing [ALT] and [▼] and then scrolling up or down using the [▼] or [▲] keys. Note that the TX frequency changes as the RX frequency is changed.
The other settings, including RX/TX Squelch Tone, Modulation, Traffic Rate, COMSEC Key, Repeater Delay, Fade Bridge, Crypto Synchronization and Squelch Level are currently not implemented.