BK Technologies

One of the most important and critical factors in the Fire Service, is Communications. Here is the links for those that use the BK / RELM hand held and mobile radios. If your KNG P or M radio has the firmware listed as 5.6.0a, 5.6.1, or 5.6.2 I would remove that and install what the Manufacturer lists as 5.5.0.S.

[As of 2-14-2023] There are NO Firmware updates beyond the 5.5.0.S Firmware release of 12-1-2021. 

RES Software is Updated to the 5.8.20 version. 

As of 3-2022, The following for KNG radios: “BK Technologies has identified a potential issue which could result in a radio not powering up when the radio operator places the switch into the on position. This condition has only been noted during the power up sequence and has not been noted after the radio has gone through a successful power up sequence.”

KNG Radio’s Not powering up BK Service Bulletin as of 12-1-21 is for Firmware 5.5.0.S use the link below to get the service bulletin.


ALSO NOTE: the BKR’s have a list of Service Bulletings that if you are using the BKR, radios you should look at:

BKR Service Bulletins


Keep up to date on the Service Bulletins and Manuals.



The Latest Firmware update version is [5.5.0r as of 4/27/21]


And as far as the Firmware is concerned here is the link to Firmware and its related Release Notes: