B7B-PrK

Crew control of Prima-KV through B7B-PrK

The B7B-PrK allows remote operation of the Prima-KV station from the cockpit. The crew can select prepared channels, set the required frequency, choose the emission mode and control the radio station according to the communication task. This is especially important for HF communication, where the station may be used on different assigned frequencies depending on route, region, operator procedures or communication schedule. The panel reduces the need for direct technical access to the radio equipment and keeps communication control in the normal pilot working area.

B7B-PrK channel and frequency selection

The control panel works with the frequency range of the Prima-KV radio station and supports operation with programmable memory channels. In standard use, the required communication channels can be prepared in advance, and the crew can switch between them from the front panel. This is more convenient than entering every frequency manually during flight. The B7B-PrK is therefore not only a set of switches; it is the operator interface for the complete radio system, transferring the selected frequency, channel number and operating mode to the transceiver.

Red cockpit lighting of the B7B-PrK panel

The “B” version of the B7B-PrK is associated with red illumination of the front-panel markings and control elements. This matters in cockpit installations where lighting color must match the aircraft’s night-vision and instrument-lighting requirements. Red illumination is commonly used to preserve visibility in low-light conditions and reduce distraction during night operation. A similar control panel may exist with another lighting color, so the exact designation should be checked carefully before supply. For replacement, B7B-PrK should not be confused with green-light versions if the cockpit standard requires red lighting.

B7B-PrK connection with the B1-PrK transceiver

The B7B-PrK works as a remote digital control terminal for the B1-PrK transceiver unit. It is connected to the radio station by an aircraft wiring harness and exchanges commands with the main radio block. Depending on the version of the Prima-KV station, control data may be transmitted through aircraft digital interfaces or internal serial communication lines. The panel also receives power, lighting supply and control signals through the inter-block wiring. Because of this, a fault in the panel, harness or transceiver input circuit can look like a radio control failure.

Indication and built-in control functions of B7B-PrK

The B7B-PrK is used not only for frequency and mode selection, but also for displaying operating information and supporting built-in test functions. The panel can indicate the selected channel, operating state and service information depending on the exact version and system configuration. Built-in control logic may provide a serviceability indication or fault code display for troubleshooting. In maintenance, this is useful because it helps separate a panel issue from a transceiver, antenna matching unit, power supply or wiring problem.

Installation and supply of B7B-PrK

On Mi-8 / Mi-17 family helicopters, the B7B-PrK can be installed on the central cockpit console, upper electrical panel or other approved communication control panel area depending on the aircraft modification. On fixed-wing aircraft, it may be mounted in the radio control console or avionics control panel. For procurement, the exact panel designation, illumination color, compatibility with the installed Prima-KV version and connector configuration must be checked. The unit may be supplied as a separate aircraft technical item or as part of a complete Prima-KV radio station set.