In response to DOD tender, Benbro designed and manufactured a battery (and mains) powered portable PA Amplifier that could be mounted on the rail of every ship and patrol boat in the entire RAN fleet. It can also be mounted on its custom carry case or securely stowed within it.
The equipment is capable of producing SPL (sound pressure level) of 140dB at 1m or 80dB at a range of 1 kilometre.
The amplifier is fitted with a military frequency radio headset microphone, a hand held microphone and an auxiliary input for pre-recorded multi lingual messages.
Benbro supervised all mil spec approvals and acceptance tests including intelligibility tests on Narrabeen Lake, Sydney Harbour and Lake Burley Griffin.
As the resulting performance was an order of magnitude improvement on the megaphones we named the product "Teraphone."