Control the uncontrollable – An anachronistic approach for contemporary automation

Many measurement instruments can now be operated remotely using the remote desktop functionality provided by contemporary computer operating systems. This makes the use of such instruments very convenient, as the status of the measurement can be monitored remotely. In addition, changes in environmental conditions can be avoided when presence at the instrument is no longer required for operation. However, there are some well-established proprietary measurement systems in use that use "historical" hardware that does not provide such functionality. The radius measurement setup for spherical sections at PTB is an example of such a system. The Fizeau interferometer of the setup is controlled by a Windows 2000 personal computer. Although it is connected to a (restricted) network, it lacks the ability to interact remotely with the measurement software. In this contribution we show how it is possible to provide rudimentary remote control of the interferometer using automation freeware tools such as AutoIt or AutoHotkey.