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Dutch / Nederlands

Diary, May 2020

Sun Mon Tue Wed Thu Fri Sat
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Saturday, May 2, 2020


I got the following two books:

Sunday, May 3, 2020

Border and marke stones

Conny and I went on a biking and walking trip again. We first visited the Groot Brunink estate again. We found a small path throught the fields that Conny did not know yet. After we had walked around for about an hour, not counting the short break we took (during which Conny took a picture of me), we continued on bike. We first biked to the border with Germany. There we found the marke stone, named Werthepaal, which is at the cross point of four markes, three in the Netherlands: Esmarke, Usselo, and Buurse, and one in Germany: Alstätte. This stone also marks the border with Germany. It was placed there in 1743 but in the seventies it was lost for some time and when found again, placed on a new foundation at the original location. We continued along the border to the South. We found another border stone, with the offical number 840-B, called: "pfael an der Mesemate". We biked through 'Witte Veen', where it was quite busy, and Conny led me to another marke stone named Veenpaal. This one looked quite new, and indeed, it was not an original stone, but a replica, placed there in 2013 and officially revealed on November 14, 2015. At home we took some time to do some research about border stones.

Tuesday, May 5, 2020

"Digital" mirror date

Today is a "Digital" mirror date, the first for the date formats MM/DD/YYYY and YYYY.MM.DD, and the second for the format DD-MM-YYYY. This is the fifth special date of this year.

Herd immunity

Today, the news came that Sanquin, the Dutch organization for blood and blood product, announced that they have ordered a milion tests for the SARS-CoV-19 virus in the research about immunity for the virus. They want to use this tests in their ongoing research about herd immunity, but also for the extraction of antibodies that could protect vunerable people agains becoming infected. Some weeks ago, the already concluded that about 3% of the population had been infected. With the current number of new infection, I cannot believe this percentage has reached 10% by now. This while for herd immunity you need somewhere between 29% and 74% infection rate based on the estimated of the infection rate. It is difficult to estimated the actual infection rate, because all the lock-down measures make it substantially lower. Without these measures, you might need more than 50% infection rate for herd immunity. To me, this research in herd immunity seems rather useless. Would it not be much beter to use the test all the people who think that they were infected and do some reseach into what are the major risc factors for getting infected and what are the most effective counter measures to be taken to avoid another outbreak? I heard some story about someone who got infected on a skiing trip, but did not infect his family members while being in quarantine when he was ill. It seems that Iceland has succeeded in eradicating COVID-19 by extensive testing and tracking. It seems that the Dutch public health services do not know if they are ready to test teachers now that primary education is going to be reopened next week and that they are not able to actively track cases that test positive. It sounds like bureacrating problems are preventing them from doing this.

Thursday, May 7, 2020

Test and track

Yesterday evening, our government presented the provisional road map for ending the lock-down measures. During the press conference, the government said they would focus on testing and tracking. The plan is that from June 1, tests will be made available to everyone, not just restricted to certain professions, as it has been up to now. The number of positive cases are slowly dropping, so it would be no problem. There will also be an experiment with opening some care homes. As far as I know, the one that Andy lives at, is not included. No mention was made about mental health care, which some people are dissapointed about, because hairdresser are allowed to open again. In the past months, our government has been stating over and over again, that face mask are not useful, but now they are stating that non-medical grade face mask should be worn when making use of public transportation. The motivation for this is that the 1.5 meter distancing is not possible in public transportation. (There is still a shortage of medical grade face mask.) There is no evidence that the 1.5 meter distancing rule has been the most effective measurement with respect to stopping the spread of the SARS-Cov-19 virus, but it seems it has been declared to the holy rule that everyone should stick to, while experts recently announced that people still having trouble with proper hand washing procedures.

Sunday, May 10, 2020


This morning, Conny and I went biking and walking around the Zonnebeek estate. We walker around the forest for almost an hour. There were quite a lot of mosquitos. Half way we had a look at the american style country house, which was build around 1907 by (Jan) Bernard van Heek and Edwina Burr Ewing, who came from Nashville, Tennessee. They donated a large part of their art collection to Rijksmuseum Twenthe. They also donated the Buursezand, a large nature area, to Vereniging Natuurmonumenten. We continued biking a came along another marke stone, the Leppepaal or Leppinkpaal, which is in the middle of a field. It is standing at the border of the marke Usselo and Buurse. We continued biking and crossed the Buursezand.

Thursday, May 14, 2020

Superclean Dreammachine

I found a website of the radio program Superclean Dreammachine. This program was made and presented by Ad Visser and ran from May 15, 1968 to September 29, 1980. (He also presented the TV show TopPop.) I often listened to the radio program because it had a mix of alternative music styles often with synthesizers. I even remember having listened to some dummy head recordings supposively made in Egypt, but I am not totally sure it was part of this program. Several times, I recorded the program on a cassete tape. I did this on May 29, 1978. The recording referred to on the website is this recording. The show started (some songs from) with the album Shpritsz. The next part was announced with: "The legends of King Arthur and the Knights of the Round Table. Luister naar de muziek van ex-jazz musicant Rick Wakeman. Sinds kort weer terug samen met The Royal Philharmonic Orchestra." I liked it very much and listened to it many times. I still have the tape somewhere in the attic. I tried to find the recording and I even ordered The Myths and Legends of King Arthur and the Knights of the Round Table only to discover that this was not the recording I was seeking after. Tonight, I discovered that it was actual the LP The Royal Philharmonic Orchestra plays Rick Wakeman that was play. I am happy that I have found this recording after so many years.

Friday, May 15, 2020

-1.8° Celsius

Last night, between 5 and 6, the temperature at Airport Twenthe at 1.5 meter height dropped to -1.8° Celsius, while at 10 cm the temperature dropped to -6.9° Celsius. This broke the record of -1.2° of 1973. This type of low temperatures, do happen more often during this period of the year, and a lot of records have been broken in the past twenty years, which seems a little counter intuitive. One reason that the temperature dropped so low, is that the air is relatively dry. This causes clouds to disappear during the night and air to cool faster. We get this dry air because of winds from the North and the East. It has been this type of weather sinds the start of April with only a little rain, less than the driest year, 1976, on record. It is caused by high pressure systems North passing over Scandinavia.


At 17:01:45, I bought the book Geek Wisdom: The Sacred Teachings of Nerd Culture written by N. K. Jemisin, Zaki Hasan, Genevieve Valentine, and Eric San Juan in English, and published by Quirk Books in 2011, ISBN:9781594745270, from charity shop Het Goed for € 2.00.

Thursday, May 21, 2020

Dew walking

Conny and I followed the old tradition of 'dew walking' ('dauwtrappen' in Dutch), which involves going on a bike trip early in the morning of Ascension Day. We left at about a quarter past five. When we came outside of the city, we noticed mist over a lot of fields and also over the lake at Ruthbeek. We planned to scout for border poles along the border with Germany. Yesterday evening, I had compiled a route. This are the border poles that we found: From there we biked home.

Friday, May 22, 2020

Resistance against measures

The resistance against the COVID-19 measures is increasing in particular agains the 1.5 meter distance rule. Yesterday, the weather during Ascension day was quite nice, so many parks, beaches and recreation areas were crowded and many people ignored the distancing rules. Some people from the catering industry have started a facebook group agains the measures, which are difficult to apply when they are allowed to open on the first of June. There is also criticism from scientists, like a Ira Helsloot, professor of Safety Management at Radboud University, who states (Google translate translation from Dutch): "If you look back in the statistics, we know that the 'intelligent lockdown' would not have been necessary."and continues to explain that all other measures, like staying home when having a cold, had the greatest effect. There are also people pointing at the evidence for aerosol transmission of COVID-19, especially in crowded, noisy indoor locations, where people are talking loud and/or singing. If transmation does not happen through aerosols, as the RIVM is claiming, there is no need to keep the 1.5 meter distance when people are not coughing and/or sneezing. There are also people who have a problem with the fact that the government (and the RIVM) are still aiming for herd immunity and not aiming at containment. In the worst infected region, around 10% of the population has been infected. In other areas, like ours, it is around 3%, but in most areas it is even lower. And even in our area the percentage is probably so high due to a number of localized outbreaks. The RIVM is stating that a vacin may not be effective and that herd immunity is the only possibility. But at the current rate it is going to take years before the required infection rate is achieved, and it is still an open question whether someone who has been infected, will remain immune for many years or that the virus will mutate, because corona viruses are known to cause repeated infections in people throughout their lives. See also this interesting timeline with respect to COVID-19 in The Netherlands.

Monday, May 25, 2020


This afternoon, I discovered that the little cestnut tree has withered. I must admit that I have not watered the flower pot is planted in and that it must not have had enough water due to the extreme dry and sunny weather of the past weeks. I will try to remember to water it in the coming weeks.

Tuesday, May 26, 2020

Noise Engine 1

In the evening, I went to TkkrLab, where there were but a few people. I bought a breadboard from the vending machine and went to experiment with the 40106 IC from the 4000-series integrated circuits, which has six inverting Schmitt triggers. I used three of these to make a circuit. For a short demo, see the Noise Engine 1 YouTube video.

Sunday, May 31, 2020


Conny and I went on another hunt for border poles. This time our goal was the Drilandstein, a border pole on the border of The Netherlands and the German states North Rhine-Westphalia and Lower Saxony.

The poles we encountered are:

Some links (in Dutch) with information about poles along the route that we took:

This months interesting links

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