Teslascope

The Teslascope was a device, created by Nikola Tesla. According to Dorothy Skerrit, he used it to intercept the Mars signal in 1903. (TV: Nikola Tesla's Night of Terror)

Behind the scenes
In the real world, though Nikola Tesla is purported to have made such a device by this time, it was only later coined the "Tesla scope" by Tesla's apprentice Arthur Matthews, after the two constructed a smaller version together in 1918.