C42 Set Commander's Mic

[David Dunlop]

Can anyone tell me the purpose of the two terminal bayonet socket on the side of this particular version of the C42 Set Microphone? On the outside of the socket is the ID: YA 11421. One of my two headgear assemblies has a small black rubber cap fitted to this socket to keep the elements out. This cap is missing from the mic in the photo.

I have not been able to find any reference to the use of this socket in any of the Canadian C42 Manuals.

Also, if anyone has a spare black cap for this socket laying about, please let me know.

I am thinking it may be a fitting for additional wireless equipment, or perhaps a terminal for attaching test equipment.

David