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HAM-Radio 2010 Friederichshafen |
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Written by Robert Langenhuysen
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Friday, 30 July 2010 21:34 |
Who, towards the end of June, was looking around on the European motorways, would find a remarkable number of cars driving along with magnetic antenna basis. Those antenna-lengths would vary between half a meter on the roof to over 4 meters mounted on the bumper. Thousands of radio-hams from all over Europe at the time were gathering in the wonderful Southern German city of Friedrichshafen on Boden-lake. And not just to enjoy the sight of the Swiss mountains or the “Gutbürgerliche Küche” [the good down-to-earth kichen] or to join a Zeppelin flight. The main reason was to visit “Ham Radio” - Europe’s most extensive meeting for radio-amateurs, attend interesting lectures, tighten acquaintances, and what else, score hotly covetted components/parts at the fair or to admire and sometimes even buy the latest shiny transceivers.
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Invitation for U the Opera |
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Written by Ard Hartsuijker
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Sunday, 13 June 2010 14:23 |
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There are no translations available.
Foto’s van Jan van Muijlwijk en Julia Gunther.
Nu eens geen SETI maar Star Trek in de Dwingeloo radiotelescoop...
In CAMRAS Schotelbulletin 2010-16 maakte Jan van Muijlwijk al melding van het bezoek op zondag 18 april van een filmploeg in de Dwingeloo telescoop. Zij kwamen opnamen maken van het in het heelal sturen van een radioboodschap in Klingontaal. Jan schreef dat het ging over een mengeling van science fiction en kunst. Maar wat was er werkelijk aan de hand en wat werd er nu precies ‘opgebeamd’? |
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Written by Jan van Muijlwijk
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Wednesday, 05 May 2010 20:11 |
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There are no translations available.
Space, the final frontier …
Ook radio amateurs houden zich hier mee bezig. Interessante link:
http://www.esa.int/esaHS/SEMNN2HMI8G_index_0.html
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DAVID AND GOLIATH (Single yagi versus DT) |
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Written by Frans PE1RXJ
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Tuesday, 09 December 2008 13:29 |
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During the weekend of November 14-16th a lot of activities have taken place around the Radio Telescope in Dwingeloo, short named: DT.
Among those an EME contest in where a lot of HAM’s were active. Since the DT has a remarkable high gain on the higher frequencies it should be possible to receive relative weak stations as well.
The question is how far can we go?
During my activities with scouting groups it came to me to include both the moon and the DT in the yearly programs that include an amateur radio activity: ‘Jamboree on the Air’ (JOTA).
That could mean the JOTA stations using temporary equipment, off the shelf transceivers and simple antennas shall be able to be heard at the DT. Using WEB streaming the scouts should be able to hear their own reflected signals and respond to that, thus establishing a contact!
The DT will be the main player in the game and my goal now is to prove it will be possible. |
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Written by Robert Langenhuysen
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Tuesday, 11 November 2008 21:44 |
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Father Jacob and the speed of light
When doing scientific investigations it is very useful to understand which of the fundamental parameters are playing a role in the investigation.
The speed of light, often indicated with the symbol “c”, is such a constant parameter.
Visualizing this value is often difficult for a lot of us.
Many from us know that the speed of light is much higher then the speed of sound, referring to a lightning strike seen far away but hearing the sound much later. Counting the amount of seconds multiplied by 300m gives you an indication of how far away the lightning strike was.
For radio waves it becomes a bit more complex to find a good practical example.
All hams and physicists know the parameter for light speed as 300.000km per second, but making it visible is a different story. This is because we don’t have a daily chance to find out.
Running EME contacts (see www.camras.nl:8901), the operators know that between transmit and receive there is always a delay of 2.5seconds. This is irrespective of the mode one is using. Since voice messages can only be done successful using large antenna’s, like our DT, you will not often be able to find this phenomena.
It will be more likely found on the many CW signals reflecting from the moon. Jan van Muijlwijk, PA3FXB, one of the operators of PI9CAM, has performed a very nice experiment to show this effect. Using the DT, he started to sing the well known “Father Jacob” song, while transmitting. He used this section of the canon song ' Father Jacob' once it was reflected by the moon, he started singing as the second voice “Father Jacob” etc etc. We could not think of a more practical example how to visualize the speed of light. To better understand, one should know the distance between Earth – Moon is approx. 380.000km.
A nice example of how free time experiments can contribute to a better understanding of scientific fundamentals. |
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