News Sat Feb 10 (2007) -- Fri Apr 22 (2016)
News Tue Jan 25 (2005) -- Mon Sep 25 (2006)
News Fri Jan 09 (2004) -- Tue Jan 25 (2005)
News Wed Aug 27 (2003) -- Tue Dec 16 (2003)
News Tue Jun 03 (2003) -- Thu Aug 14 (2003)
News Mon Mar 17 (2003) -- Thu May 22 (2003)
News Wed Dec 04 (2002) -- Mon Mar 17 (2003)
News Mon Oct 21 (2002) -- Thu Nov 28 (2002)
Monday next, my son Willem travels to Bangui in the Central African Republic for aircraft maintenance. Now I work on ten NightReaders of the using-next-to-empty-batteries type, that he could take with him. The first prototype that Willem took there three weeks ago was received with enthusiasm by the local people that he contacted through the Medcin Sans Frontieres. With this new series of ten, I work on a wider base for local experimentation, as up to now I had no practical experience of how the gadget would function. Expecting similar positive response, I prepare to visit Bangui mid December for 4 weeks stay. Other project should be presented there as well, such as the rope pump, the Demo Sticks and the pulley.
I should present pictures here of these items, but my PC has broken down, so I can not access the image folder.
The design for the NightReader gets a better base. Paula worked on the method for making the battery bags. Jos Knoop checked the electrical circuit for limiting tension for the two LED's used in the NightReader. He supports the circuit as advised to me by Frans Spiering. It has to be checked if an extra condensor should be added parallel to the resistor that governs the tension produced by the transistor.
Ten newest model NightReaders to go to Bangui next week
Fri Oct 11 (2002)
I found it difficult to decide on the wiring between the electrical components, but the outcome is satisfying for the time being. The outcome is: components and insolated bits of wiring on the outward side of the mounting board, all soldering of components an wires on the other side. This safeguards components from being damaged by a hot soldering device. In practice, the wiring results in a protective cover over the electrical components. It proved easy to solder with primitive means. It was well possible to visually check these connections.
The mounting board is actually the little wooden handle, with the middle section reduced to 3 mm.. It proved easy to make little holes to pass the electric wiring. I used a sharpened bicycle spoke, bent in a special way (soon an image will be made available).
Again Willem will stay in Bangui for only one week. News on how the NightReaders will perform will soon be known.
Demotech is a dwelling made out of ideas in which some people sometimes live. It may help to gather these ideas under the one name "Demotech", but sometimes it feels more real to present oneself not as "We, the company", but simply as I, the writer.
I-mode for Diary
Wed Oct 09 (2002)
As I, Reinder van Tijen, write these news items, I could also write them as personal comments, as a kind of diary. I expect reporting on progress with Demotech work, will be nicer work if I can do it from a personal point of view.
There is a good reason to start today in this "I-mode". New today is the ease of adding NEWS to this page. Marc programmed all the buttons for easy access and this is the first time I use them.
Real news today is the stack of battery bags and holders for electronic parts, both in preparation for the NightReaders to be taken next week to Bangui in the Central African Republic. I am fascinated by the enthusiasm on reception of the first NightReader by the local people. I want to know how it works out when more people will use this little light. Kim, the anthropologist, working in Bangui for Doctors without Borders, will listen to the comments and let me know what people think about it.
The plan to go to Bangui myself takes more shape. I hope to verify the NightReader fulfills a real need. If so, I hope to encourage local manufacture. The design as it is now, should make this possible.
I-mode, diary fashion of writing news starts today, as Marc has programmed useful buttons to facilitate this. News was working with my neighbor Paula on NightReader parts to be shipped to Bangui next week.
Again some improvement in the way this news item is organized. "News" was a separate HTML-file, now it is a subrecord, organized like the other sub-records. Similar as with the other sub-records, it is possible to react to any item of 'news' in a forum page.
Sat Oct 05 (2002)
When 'news' has become 'old news', it will be linked to the sub-record to which this item is related.
Marc has written some PHP code for Demotech's SQL database to display in each record all the subrecords that belong to it. These sub-records, such as the publications listed in the record 'Publications' are from now on automatically displayed in a list. The title of the subrecord is clickable, as to faciliate access. Also a summery will be displayed together with a small picture for each sub-records.
It will take some time to write these summaries, before we can wipe the old way of displaying.
New way of displaying the subrecords
Fri Sep 20 (2002)
Demotech has a Senegalese client, Ives Vaye, living in the Netherlands. His foundation "Keur Mouss?" promotes more efficient farming in regard of the use of water and the better managment of a garden in his home country. Ives' foundation supports a field project near Dakar, first of all with the constructin of a 40 m. deep well.
Cutting the rubber sides of the pulley for Senegal
Mon Sep 16 (2002)
Demotech is involved with the development of a pully to lift water from this well, to be constructed out of rubber from a car tire and wood. In The Gambia (a very similar and nearby region) locally made metal pullies are for sale.
We found these pullies wear out fast, are concidered expensive and are not generally used. This is very different from the country side in Indonesia, where for wells of similar depth the use of pullies is general. For Demotech a reason to work on an alternative.
The Demotech design for such an alternative asks for a precisely cut ring, cut loose from the side wall of the tire, includng the metal wire reinforcement, that gives the ring its stifness. We had to find out how to cut it in an efficient way, without any danger for the worker cutting himself or his helper with the very sharp knive needed for cutting rubber.
We found a proper working position: the rubber ring is put around the knees. By spreading the legs outwards, the ring is kept in place while working on it with the knive. There is no need for a helper, as one hand of the worker is free to pull at the cut-away strip of rubber. Pulling with some force on this strip helps much to ease the cutting. Both of us found this an effective and comfortabel working position.
We prepare this design for manufacturing by local craftsman in Senegal and elsewhere. A sharp knife should then be about all the tooling needed.
The translation of the Dutch paper will be available shortly, thanks to Angeliek, who is pretty good at fixing lousy translations.
Vision entrepeneurship after 9/11
Wed Sep 11 (2002)
For a short time only! A separate list is in the making for Demotech publications available in other languages (right now only Dutch). Just temporary we put the Dutch papers in the same list as those already in English.
Mix of Demotech papers in English and Dutch
Wed Sep 11 (2002)
Our frameless web machine is working smoothly now. Though a lot of details will have to be fixed in the near future, we have a better base to build on.
New layout from now on!
Wed Sep 04 (2002)
Please report to us anything still wrong through the forum page linked to "Constructing this website".
As this website is still under construction, we have to be dynamic and make improvements. The list for items to be changed is long, but slowly results will come. Some of the ideas on this programm are menthioned in Constructing this Website . However much of the work is on the database in interaction with the programm that links this database to the server. Marc van der Kamp is working on it now. One of these days the new setup will be published on the web. Main difference is that frames (a way of composing webpages) are not anymore used. Making bookmarks works more accurate.
New layout for the Demotech website
Mon Sep 02 (2002)
The frameless setup also makes it possibe to change the whole layout without changing anything of the content, the actual information. So the present "skin" will certainly not be the last one!
Work on the Projection Drawing Table, to center the lift and to find an alternative for the existing foot.
Work on the foot and the lift of the Projection drawing table
Tue Aug 27 (2002)
The lift worked well with the glider out of a strip tin plus a set of rolers at the bottom. Next was he construction of the shelve that has to carry the projector. The outcome is a box that turns inside the middle space of the lift. This box is stiff, can hinge upwards between the gliders of the lift and when folded, can store some stuff that the user wants to keep with the drawing table when not used.
Rollers to center the lift between the legs of the table proved superfluous, when this function was carried out by two strips of sheet metal attached to the inside lowerpart of the legs.
The foldable footframe has been replaced by two simple stands, holding the legs apart. This does not impair the stability.
News Tue Aug 27 (2002) -- Mon Jul 01 (2002)