The early days of radio in the Netherlands

In the early days of radio in the Netherlands, broadcasting and ham radio hobby largely coincided. There was experimentation with transmitters, and that included both 1-to-1 communication and, a little later, broadcasting for groups of listeners.

Such transmissions occurred without a license. Eventually it was decided that the valuable thought frequencies below 1500 kHz were reserved for professional use. The amateurs with their experimentation got everything above that, because there wasn't much use for them.

The reality turned out to be different be, but that's a story that doesn't really belong to this topic.

Just outline the period we are talking about here. The first radio amateurs were around just after 1900. Marconi who based his work to a good part on the work of Nikola Tesla began experimenting around 1890. He demonstrated the invention of wireless communication for first to the public in 1896

Around 1901, Marconi proved that radio signals travelled beyond the visible horizon. Just two years later, he covered the distance from Cornwall in southwestern UK to Newfoundland in far eastern Canada with a telegram, a congratulatory message in Morse code from U.S. President Theodore Roosevelt to King Edward VII of the United Kingdom. A few hours later followed the reply from the English monarch in the other direction. This was a distance of 3,200 km.

Around 1902, the first kits for experimental transmitters and receivers for amateurs appeared on the market in the U.S., and the first amateur magazine dates from another year earlier.

The first amateur radio association, the Wireless Telegraph Club of Columbia University, founded by students of that association dates from 1908.

In fact, the oldest surviving amateur association is the Wireless Institute of Australia, the WIA, which was founded in 1910.

In that early period, spark transmitters were primarily used. These are extremely simple transmitters, consisting of only a capacitor and a coil, which together form a filter, not a good filter like those used today, but still a filter. The coil is not connected to anything, but there is a wire near the circuit with an air gap, similar to the air gap in a spark plug in a gasoline engine.

Also in the same way as in a gasoline engine, a high voltage is generated with an ignition coil, and so while crackling, you allow the spark to jump over to the circuit, which somewhat limits the bandwidth of the resulting interference.

The persistent sparks are switched on and off with a morsesignal signal key, and thus communication takes place.

With the later transmitters, there could be many dozens of signals on the same bandwidth where one spark transmitter sat. No wonder, then, that later users were often annoyed by the use of this type of transmitter, which in the latter days was used almost exclusively by radio amateurs.

Receiving was done in the early days with a crystal detector. This involved making a diode by using a pin to locate a good working piece on a plate with a contaminated semiconductor. In later years, simple electron tubes were used for this, such as in those early years a double grid tube.

The English name for a marconist on a ship is sparks, which obviously comes from these spark transmitters, in the Netherlands the similar term vonkenboer (spark seller) has been in use for the same person. Ships from about 1905 onwards also initially used these types of spark transmitters. However, the equipment aboard ships such as the titanic was not for emergency traffic, but mainly for sending telegrams for and from the wealthy passengers on board.

As will be clear, transmitters at that time did not come from the factory. At most, factory parts could sometimes be obtained. And so until well into the 1930s, everything was built in-house. That included radios to listen to broadcasting, because most people simply could not afford the radios that were for sale, if they were for sale at all.

The latter was also part of the reason for the establishment of VARA, which stands for Vereniging Arbeiders Radio Amateurs. The VARA did broadcasts, also published a broadcasting magazine, but also sold popular kits to make their own radios for a price that a worker of that time could afford.

Hans Henricus Schotanus à Steringa Idzerda was born on September 26, 1885 in the town of Weidum, which is located in Friesland below Leeuwarden. He was called Hanso Idzerda for short, and for those familiar with his nickname Idz, written as Idz. Later publications often refer to Steringa Idzerda. He was the son of a country doctor. By the way, in a period before the, say modern medical science. Infant mortality in the Netherlands was enormous, as was the mortality of mothers in childbirth. And because there were no antibiotics yet, the doctors who usually had most of their knowledge from those from whom they had taken over the practice were helpless against even simple infectious diseases.

This is to create a time picture. My own grandfather is from the mid-90s of the 19th century, and I am always amazed that someone I knew so well was able to see these times with their own eyes.

His name was a variant of his grandfather's name by a slip of the tongue, by and slip of the civil registry. Grandfather on father's side was also a doctor and there were more people with that profession in his family. Nevertheless, Hanso decided to study engineering at the Rheinisches Technikum in Bingen am Rhein, Germany. He graduated there in 1913 as an electrical engineer.

He then settled in Scheveningen in the Ten Hovestraat as an independent consultant for the application of electricity in every field. By the way, the Ten Hovestraat still exists, and from the looks of it on Street View, so do the houses from that era.

To be clear, his last name was Idzerda, the names Hans Henricus Schotanus à Steringa with an accent on the a, were first names. But because of the way he registered in The Hague, the first names Schotanus à Steringa were included in the surname, with Hanso Henricus as first name.

According to wikipedia, Idzerda focused on the development of radio transmitting and receiving equipment.

He had his own company under the name Technisch Bureau Wireless, and there he began manufacturing equipment, which he supplied to the Dutch army, among others. This company was probably located at Beukstraat 8-10 in The Hague.

During World War I, during which the Netherlands was neutral, he experimented from the vicarage of his parents-in-law, the Nicolaï family in Mantgum. With self-built sounding equipment he was able to determine the location of radio transmitters, including German zeppelins sailing to England. The Dutch armed forces made grateful use of his information.

He also succeeded in further developing a triode lamp that had already been invented in America by Lee De Forest in 1906.

Philips' Eindhoven incandescent lamp factory took the lamp he improved into production in 1918 under the name PH-IDZ (Philips Ideezet). The lamp had a limitation, as it was only suitable for processing morsesignals. It was not yet possible to send word and music into the radiowaves.

To achieve this, broadcast triode tubes with a wider frequency bandwidth and greater power were needed. Together with Philips, Idzerda developed some improved test specimens.

During the Utrecht exhibition in late February 1919, he demonstrated for the first time in the Netherlands broadcasting over the ether of sound over a distance of 1,200 meters. Excitement among the audience was great and even the then Queen Wilhelmina came to listen.

In the Netherlands, by the way, unlike in a number of other countries, the ether was off-limits to private individuals. Radio amateurs in the Netherlands were in fact illegal, but probably because in other countries this hobby was often allowed, it was also tolerated in the Netherlands.

Legal were only military and maritime communications. And so in those early days that could only be done in Morse code.

Nevertheless, radio amateurs at that time were therefore already exploring the airwaves extensively. With homemade receivers they listened to the Morse messages. Incidentally, there was even a listening ban in the Netherlands until 1917. The latter ban was lifted after a demonstration to Minister Lely. However, transmitting remains prohibited. But control is virtually non-existent.

For most Dutch people radio is inaccessible in those early days. In those days it is a hobby for handy amateurs who with technical knowledge are able to build their own radio. This can be read on the website of Sound and Vision.

Idzerda wanted a radio for the masses. He wanted to make radio the medium for a large audience that it indeed was later for a long time.

As an inventor and builder of individual radio parts and complete radios, he also saw an outlet for his products. However, not many people will buy those radios if they can only listen to Morse code.

Idzerda therefore decided to build his own transmitter, apply for a broadcasting license and start making radio broadcasts.

What is remarkable, by the way. People now complain about the amount of English in Dutch. However, there were no common words in Dutch back then for wireless and for broadcasting. And you see that in the name of Idzerda's company the word Wireless appears. Similarly, at that time the word for broadcast was broadcasting. There was a Dutch word for that only later.