Does anyone have knowledge of who employs the technicians for maintaining airport electronics?

In the US, the FAA (federal aviation administration - a government agency) is responsible for the maintenance of all electronic systems related to air traffic control.

Is there an equivalent government agency or private employer in NZ that someone knows of?

I found a company on the internet, "Airways": http://www.airways.co.nz/index.asp

Any help in positively identifying the employer, or other information, would be appreciated!

Mike