Diary

This is the seventh article in a series about the Elektorlive-event.

Mikrokopter by Holger Buss and Ingo Busker a great project. It is a miniature helicopter equipped with four propellors. The heart of the system is a small controller board with an AVR microcontroller from Atmel: An ATMEGA 644 working on a 20 Mhz clock frequency. The board can be so small because SMD components have been used. It features a lot of interesting periferals: 3 piezo gyros, a 3D acceleration sensor and optionally also a pressure sensor for measuringing the altitude. The four propellors are directly driven by brushless electric motors, with I2C-controlled driver chips.

The Microkopter can be controlled with a normal remote control used for model airplanes, but the receiver has been modified for this project: It does not have to control servos in this project, so the multiplexed signal is fed directly into the microcontroller without decoding the information for individual servos.

The system is also capable of autonomous flight, but unfortunately it is not allowed to have autonomously flying objects in the open air. I saw it flying inside the Evoluon and I thought I had made a nice video clip of it, but it was not recorded. So please watch a clip made by the builders instead.

Labels: Elektorlive

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This is the sixth article in a series about the Elektorlive-event.

The Eindhoven company Shapeways specializes in "3D-printing". You can upload a 3D-design to their website and they will "print" it for you. That way any shape can be produced.

In the pictures you can see some phantasy objects giving a demonstration of the possibilities, but there are lots of practical applications, like building a case for the prototype of you latest invention for instance.

The products can be made out of different materials: Hard or elastic, transparent or opaque, even metals are possible. The costs for this service are really only determined by the type and amount of material used. You can make a bracelet for instance for $10 but a fruit bowl would cost you hundreds of dollars...

Labels: Elektorlive

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This is the fifth article in a series about the Elektorlive-event

Elektor has published many articles on audio amplifiers over the years. I started reading the magazine in 1974, but this is an even older design: The "Edwin-amplifier" from 1971. Harry Baggen had borrowed it from Jan Buiting's collection to be able to show "how it all started".

The Edwin-amplifier has some great advantages for a hobby-project: You don't have to tune any bias current and there are no special requirements for the pairing of the two power transistors. When little output power is needed, the energy is going directly from the driver stage (that has a class-A lay out) to the speakers. Only when more power is needed the power transistors come into play... A very clever design!

Personally I am not into building audio amplifiers. I have never even built an audio power amplifier myself. I am very glad we have integrated circuits these days: A big chip or module you can screw onto a heat sink. Just add a few capacitors and your power stage is ready!

I have built some pre-amplifiers. In the shop there are simply no pre-amps available that match all my requirements. They always have a lack of inputs and (at least back in the eighties) they had no remote control. I want to be able to connect many input sources: Tuner, TV, CD-player, pick-up, cassettedeck(s), MP3-player, computer(s) etcetera. And I want to distribute the audio signal throughout the house, so that you can keep listening as you go from room to room. Yes, my houses have always been full of wiring to connect everything together.

My main interest in this stall was not in the equipment, but in the guy behind it: Harry Baggen, editor-in-chief of Elektor and my second employer (or most important customer) for my free-lance translation work. This was the first time we ever met in Real Life! This was definitely one of the highlights for me on this day...

Labels: Electronics, Elektorlive

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This is the fourth article in a series about the Elektorlive-event.


Of course I went to see Jan Buiting, who did a talk on "retrotronics": That is vintage electronics. He had brought lots and lots of electronic equipment from the past sixty years and invited the audience to select which device interested them. He had wonderful anecdotes about the origin of each device people selected. Many stories were about Philips company, where a lot of this equipment has been produced.
For example he showed us one of the very first pagers. In our time of text messaging and wireless Internet it may be hard to imagine, but at the time the pager was invented it was a state of the art device! The size of it was about 12 x 12 x 4 inches and it weighed well over 10 lbs. Fortunately it had a strong belt that could be used to carry it on your shoulder. So it was a real portable device.
So what did it do? It was for wirelessly receiving "messages". These messages consisted of a single digit number: 1, 2, 3, 4, 5 or 6. That was all it could do. To use it you would have to make arrangements (with your boss for instance) what each of these six codes would mean...
When the system was first released to the press, the receivers did not really work yet, so the people from Philips had secretly mounted a foot switch below the table where the device was demonstrated. This way they could activate the lights by hand foot during the demonstration...
Jan's talk went on and on with one device after another. Some equipment was also passed around amongst the audience so that people could get a close look, feel and smell of them. Yes, a smell: Vintage electronics has a characteristic fragrance, you will find nowhere else these days.

The audience couldn't get enough of Jan's talk! A real success.

After the talk I took the opportunity to have a close look at some of the equipment on the tables. One table was full of old Elektor-projects. And there I found a well-conserved specimen of the SC/MP, MY first computer, which I built in 1978.
This system (published by Elektor in May 1977) had no less than 256 bytes of memory (no, not kilobytes, not Megabytes, just bytes)! It had to be programmed bit by bit with the switches you can see at the bottom of the picture.

Another beauty in the collection was this test system for vacuum tubes by Heathkit:


If youlike pictures like these, you will also like the Vintage Electronics groep on Flickr. I also found a link to this video clip there. As I said: Once upon a time all this equipment was new and modern!

Labels: Electronics, Elektorlive

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This is the third article in a series about the Elektorlive-event.

The second lecture was about fiber optics. More and more people know about this, as more and more homes are connected to the Internet (AND to cable TV AND to the phone) through optical fiber. This technique is called FTTH (Fiber To The Home). Fiber optics is not very new really. It has been in use for the "highways" of the Internet for a long time. A great advantage is the enormous speed of information transfer compared to copper wires. Another advantage is this type of cable is not sensitive to electromagnetic interference.
This is one of the reasons fiber optics is often used for information transfer along railroad tracks. The electromagnetic interference produced by a passing electric engine is very heavy indeed.
And speaking of railroads we run into another application of fiber optics: They can be used as a sensor! Optical fiber cables are very sensitive to bending and that can be used in many smart ways to make them work as a sensor.
An optical fiber can be used to check whether a track is occupied by a train, but it goes even further than that: It can be used to do detailed measurements of the condition of each individual wheel of a train as it passes by! This means the trains don't have to go to the workshop until they really need maintenance. A great reduction in cost!
This picture shows the measurement result when three wheels have passed the sensor. The first two wheels are good; the third one needs maintenance.

Optical fibers can also be used for measurements in aeroplanes and dikes. The possibilities are really amazing.

Labels: Elektorlive, trains

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This is the second article in a series about the Elektorlive-event.

The first lecture I visited was about the Elektor Internet Radio (EIR) and the speaker was Antoine Authier. Most of the speaking was done by Harald Kipp, who developed the hardware and software. The hardware is the Ethernut 3 card, which is equipped with an ARM7-processor, 256 kbyte RAM memory, Ethernet-interface and hardware for codering and decoding MP3-data. It also has a slot for MMC-/SD cards, which make it possible to extend the memory-range — a lot!

Unfortunately there was no Internet connection available at the stand, so they had to use a Southcast server they had brought along themselves for the demonstration. All that did not work very well, but still we could see this Internet radio is a very interesting piece of equipment with lots of cool possibilities.

Of course one can simply use a PC to recieve Internet radio, but that has some disadvantages. A PC consumes a lot of power, much more than is really necessary for this application. And in some situations a PC is simply not suitable. For instance it is not very practical to connect a PC to the stereo set in the living room.

The system is a great platform for creating new projects. If you build your own radio, based on open source software, it is easy to extend and adapt it for your own applications. The Ethernut board can be used to build a stand alone radio. All you need in extra hardware is a few pushbuttons and a display. And you need some software to control it all...
In the picture the card has been extended with a graphical color display.

Later that day I met Harald Kipp outside, where the smokers were flocking together in the open air. Once again it turned out that the smoking area is a great place for networking... Harald is a very inspiring person and it was nice to discuss my own ideas for applications of the Ethernut board with him. How about using the card as a Southcast server? (This would make it possible to broadcast Internet radio instead of recieve it.) Harald said it would indeed be possible for a limited number of simultaneous connections...

Labels: Electronics, Elektorlive

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Today I visited the Elektorlive event in the Evoluon in Eindhoven.
Some 1500 people had pre-registered, but the whether conditions were not optimal. It was the first snow day in this winter. But more than 1000 people did show up!

Of course most of the people there were men. There were only an handful of women and even those had only come along with their friend or husband. I think I saw only one other woman by herself. So pretty soon someone spoke to me and told me what he was thinking: "Hey, a woman here? I am surprised!"
Well, at least he had recognized me as a woman from a distance.
But as we were talking, he soon figured out there was something more going on and said: "Oooww, aha, now I understand..."
"Yes, I used to be a man", I admitted.
"So you are a transvestite?"
"No, I am a transsexual, that is quite something different!"
"It is??"
So there I was again, educating him about the differences...

Of course one could ask what on Earth I was doing at such a male-dominated event, but hey, i do work for Elektor, and I saw this as a great opportunity to finally meet this client I have been working for for eight years in real life! And I am simply interested in electronics. It is my profession!

I had carefully planned the lectures I wanted to see and that was quite a tight schedule; I had had to make some difficult choices, because it was simply impossible to see everything that interested me. Over the next few days I will cover some of the things I have seen at Elektorlive in seperate blog entries.

Labels: Electronics, Elektorlive, transition

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