I think it is more likely a civilian button, perhaps a communications button, aka "call to quarters" uniform button.
[The “CQ” call is a call to “all stations”, and it has been around since the earliest days of “wireless” or “radio”. Its use predates formal regulation of radio procedures. It is mentioned for the first time in the 1912 International Radio Regulations as
“CQ Enquiry signal employed by a station which desires to correspond“
Actual origins of CQ are disputed, one explanation is that landline telegraphers used CQ as some form of “wake-up call” to alert operators that messages were on their way, and this was carried over to wireless operation.
It formally belongs to the family of “prosigns” or “procedure signals”.
The use of CQ differs somewhat between professional or commercial radio and amateur radio.
When a commercial station calls “CQ” it is to alert the listeners that a message “to all” follows. It is implicit that no station should answer the call, unless they are mentioned in the following message.
In amateur radio, the CQ is an invitation to answer to any or all stations that have heard the call and wishes to correspond with the originating station.]