ROYAL AUSTRALIAN CORPS OF SIGNALS.
The exact date of the change from a Bi - Metal cap badge to an Anodised Aluminium cap badge is not exact as different units received this badge at different times.
It is thought to have been around the late 1970's or early 1980's. The first anodised aluminium badges were introduced in the mid 1960's and were only issued to the newly formed State infantry regiments, SASR and a new modified RNSWL badge. The rest of the Army wore bi-metal badges well into the 1970's early 1980's
. There have been a number of changes in the material used for the making of the current design of badge. Bi-Metal, Brass as well as the above Anodised Aluminium version.
My very grateful thanks to Chris Roberts who is a former Royal Australian signaller who graduated from RMC Dunstroon in 1967 where upon he was issued with a Bi-Metal cap badge. Chris says he was still purchasing Bi-Metal RA Sigs badges from the Q store in the mid 1970's.