Showcase story 10 - The development of radar technology
Waalsdorpervlakte, 1936. Researcher Johan van Soest and committee member Carl von Weiler of the Commission for Physical Combat Resources are conducting experiments with radio equipment. They notice that birds interfere with the signals of the special transmitter-receiver. For Von Weiler, this is a eureka moment. A test with airplanes later confirms their finding: the radar principle has been discovered.
By order of Minister of War Hendrik Colijn, the experiments continue. The goal is for radar technology to take over the work of the air observation posts, which currently still search for enemy aircraft with the naked eye. Anti-aircraft artillery also benefits, as radar is much more accurate than the optical and acoustic instruments they use.
In the first half of 1939, Von Weiler and Sybrand Gratama, another committee member, build the M39. This is the first functioning Dutch radar, with a range of more than fifteen kilometers. Just before the mobilization of the Dutch army, the Ministry of War secretly orders fifty radar installations from the Nederlandsche Seintoestellenfabriek in Hilversum.
Fifty years in the radar workshop
Since World War II, radar technology has continuously evolved. Major changes occurred, among other things, right after the war. The Hengelo-based company Hollandse Signaalapparaten (now Thales) equipped navy ships with rotating radars. And in the 1980s, radar technology took another major leap forward, thanks to the introduction of computer-controlled systems. Herman van der Giessen and Jack Dienst witnessed this last development up close—along with many of the preceding and following steps. The retired duo worked for nearly half a century in the radar workshop at the naval base in Den Helder.
“One thing remains the same: the cat-and-mouse game”
“The first low-frequency radar detected aircraft at up to a hundred kilometers,” says Jack, who can talk about it for hours with his colleague. “That was amazing at the time. The high-frequency radars detected targets at close range, and you could navigate with them.” “There were also dishes to control cannons at great distances,” Herman adds. “If the target’s radar returned a code, it was a friend. If no code came back? Then it was an enemy. And that enemy got a missile.” “Nowadays, the airspace is crowded with planes, birds, and drones, and there are also ballistic missiles—automatically taken out of the air within seconds,” Jack continues. “One thing remains the same: the cat-and-mouse game.”
Showpieces
Today, Herman and Jack share their knowledge of radar technology during tours of the naval base. They are also busy with a permanent exhibition that displays the development of radar technology on a timeline. Herman: “No, the M39 is not on display here. It's at TNO (the former Commission for Physical Combat Resources, ed.). But we do have similar technologies with magnetrons: the first glass signal tubes in amplifiers and receivers. Other showpieces include a beautiful receiver from 1950 with about ten tubes and a Type 271 radar. This English model was built in the early 1940s.”
“We have different departments, each in its own building,” Jack continues. “And everywhere, the most beautiful and unique components of radar technology are displayed chronologically in new showcases. Two are already in the radar workshop, and a third one is on the way. There’s also a display case in the Electronic Warfare and Radar Tubes departments and in the High-Frequency Laboratory. Finally, there's a larger case for the larger components. Each part is accompanied by a brief explanation of how the technology works.”
Inspiring youth
Herman and Jack were asked by the Naval Base to design the exhibition. Completely logical, as the two men are living encyclopedias in this area. They've been working on it for about half a day per week for the past year and a half. Their mission? “We want to inspire young people to get excited about radar technology,” says Jack. “That works much better if we pick out the most striking items and give them some character in the showcases from SDB. We are just well-meaning amateurs, but we want to approach it professionally.” “It's a gradual process,” Herman concludes. “Just like the entire development of radar. Although I do hope we’re a bit faster, haha.”
“We want to inspire young people to get excited about radar technology”
