In 1950 Rohde & Schwarz developed the first complex network analyzer, calling it the Zg diagraph. For the first time it was possible to directly measure the phase of S-parameters of a signal. The instrument was primarily found in measurements on sound and TV broadcasting antennas. But it was also used to test special cables in telecommunications, and it served microwave engineers as a Smith chart. The ZDU Zg diagraph (30 MHz to 300 MHz), introduced at the beginning of the 1950s, was followed by the ZDD (300 MHz to 2400 MHz) – at 62 kg no lightweight by present-day standards.

The first direction finder from Rohde & Schwarz was the NAP1. It was used in air traffic control as an addition to radar since the latter alone did not enable unique identification of an object in flight. In addition, the direction finder produced data that could be processed in radiomonitoring as well as ATC. This played an important role in air emergencies, ground control of sport aircraft or if radar failed. The system operated by Germany’s ATC administration at Munich Airport was a visual direction finder, the located object appearing on a screen in the form of an illuminated cursor. It was the first development of this kind in Germany after the war.

A relatively high price, not all that compact in design, and a weight of 53 kg to 66 kg – not necessarily ideal specifications for a shortwave receiver. But in every other respect the EK07 was the star of its day in shortwave radio. The signal corps of the German army opted for it when looking for a standard HF receiver. The EK07’s excellent receiving characteristics, high frequency accuracy and ease of operation convinced them. And the EK07 was rugged too. Deutsche Welle, Germany’s international broadcaster, installed the receiver in a relay station in Kigali/Rwanda. And the EK07 also stood the test on a Belgian-Dutch expedition to the South Pole in 1964.