Designers and do-it-yourself-ers all over the world, WELCOME !
- Do you beleive that it is always possible to enjoy by designing analog circuits ?
- Do you prefer designing by yourself, even by using good old discretes or common IC's, instead duplicating some unexplained IC application notes or copying some already prepared solution ?
- Do you leave in a place where to find up to date components is a serious challenge, although everyday you have new ideas ?
- When you are using a microcontroller (it happens !), are you interested into other things existing beetween the I/O register and the outside of the board ?
- Don't you mind reading some english language mistakes from a french guy ?
If you'd reply YES to all, this site is made for you !
Why I put this site online
The purpose on this site is first trying to prevent people already familiar to electronics from falling into the dark side of the "ignorant bit pushing"... These are the main dangers threatening today's electronicians. I remember some "old" classmates witch were familiar to true electronics design in the past, and witch are now just able to control a stepping motor via a 1,000$ interface board on a PC programmed without any line of code, because even assembler programming on a microcontroller is already too hardware relevant for them. I see beginners full of ideas witch are restricted to such activities because of the lack of information available around them. I see they are quickly discouraged by trying to make a simple circuit work while none is able to give some simple advice (such as information about problems like ground common impedance, capacitive coupling, line inductance and power source impedance considerations, witch are 90% of the "mysterious failure" causes into a homebrew board, even for LF and AF circuits). This is the case in France (where I live) where even experienced professional people become having some doubt about the biasing of a transistor, and I suppose it is the case in many other countries. The educational system now provides two types of electronicians: Simple executing people now called "technicians" (receiving less and less high level education nowadays) and mathematicians called "engineers" who manage to pass horribly hard exams but often never trained themself in designing something. When you are a "homebrew guy", to get information a lot of websites contain high quality information (and others not !). I don't pretend providing something better but only to add my small contribution by describing particular designs which are often less described in the field of analog circuits.
Some probably say (I already heard in my life) that analog or discrete designs are always the same since the 60's. They state that they have already passed through the step of audio and RF which are just interesting enough to have fun while they were young. I think that somebody who's saying that did not even design some digital hardware and believes that no analog experience is necessary for that... The second reason why I wrote this pages is my wish to show that today new applications of good old principes and systems can lead to surprising results. At this time we have the chance to get the possibility to build at reasonnable cost any sorts of gears by using a great choice of discretes and common IC's (and why not, around a microcontroller...). A good knowledge of analog design basis is always a great advantage for solving any kind of problems, even around a microcontroller...
The schematic bank on this site, which is intended to grow (I hope !), will propose circuits witch won't be especially difficult to build or to understand (although the site is not recommended to absolute beginners). It is always interesting to see how others are doing and to get new ideas, but that does not put back into question that anyone who really wants to get pride and pleasure by building something will have to put its personal touch. May be it is difficult at the begining, but it is necessary. Else you will really be bored by electronics after one or two years of ''practice''. It is true that a lot of people say (typical french expression): ''It is useless to re-invent the wheel''. This is often taken as a reason for applying all-done solutions, pretending that it will prevent having troubles. In fact, frequently the opposite effect occurs: that does not work and you don't know why. And that is the best way to be disgusted for ever... In that case I think the best solution is to buy a finished product, so that you do not ''re-invent the wheel'' ;-).
You had the courage to read all this grandfather's fashion text until here. You desserve the following list:
(Drawings quality is poor, but when I draw them I had not yet planned this website...)
* Progressive audio dubber for VTR (mixes pre-recorded audio with new recorded sound) -> Click here
* Audio pre-amplifier with true limiter (60 dB dynamic AGC) -> Click here
* DC-DC downconverter using one of the most common IC's in the world -> Click here
* Smart capacitive sensor (touch and approach) using no custom nor rare IC -> Click here
* Contactless and batteryless remote sensors -> Click here
* Tiny console for PC computer (use a PC as a stand alone device without monitor nor big keyboard) -> Click here
* 7W AM transmitter for MW band (excluding the optional PLL) -> Click here
