The thermionic radio valve has been out of common use for more than two decades now, having been almost totally superseded by the transistor.
During my schooldays during the 1950s, I, together with many friends was obsessed with building wireless sets from parts either given to me or salvaged from old sets obtained from jumble sales. So obsessed, in fact, that I took it up as a career, serving as radio officer in the Merchant Navy between the years 1960 and 1992. During those years, I saw the use of the valve diminish as transistors and integrated circuits rapidly took over. Working in professional radio, my interest in it as a hobby gradually diminished and even disappeared over the years.
After I left the sea, I concentrated on my alternative hobby of building model ships. My old interest in wireless was re-awakened about a year ago when the editor of a well-known radio magazine asked me to write an article updating a circuit that I had written about ten years previously. I did this, and found that the old magic was still there.
Perusing various wireless magazines and internet sites it quickly became apparent that the valve is once again becoming popular amongst home-constructers who are looking for something different. A lot of old articles are being reprinted and the letters pages are full of comments about valves and requests for further articles.
Experiences with book publishers over the years ruled out writing a conventional book and I find article writing too tedious. There can be lengthy delays (sometimes years) between having an article accepted and actually seeing it in print. I therefore decided to by-pass all normal publication channels and produce my own book on a CD disk which would run on the Microsoft Word, word processing programme. The advantage of the CD disk is that the memory capacity is so large that they can easily accommodate as much text and as many photographs or illustrations as one feels inclined to put on them. The appearance of the digital camera also solved the problem of illustrations. I have never been a very good artist or draughtsman, but I find that I can produce very professional looking circuits and drawings on my PC without having to use any complicated programmes.
This CD is mainly aimed at the beginner to valve construction. I have gone down to the very basics, keeping theory down to an absolute minimum. The accent is on safety and pleasure in the construction. No dangerous voltages have been used and no harm can come to you as far as the electronics are concerned!
More importantly, I have adopted a different approach to the projects themselves. I have combined model making with electronic techniques so that as well as working, they also present a neat and impressive finish. For the most part, I have used modern components. The main exceptions, of course, being the valves. I believe that these small radio sets are like nothing else you have seen before in this field.
Finally, I have limited myself to single valve circuits to begin with. Should this disk prove popular, I will have room to expand to two, three and four valve circuits as well as more ambitious projects such as superhets.
Although the page numbers are consecutive throughout, each chapter is complete in itself and the Fig. Numbers of each chapter begin at Fig. 1. Because of this, you only need to print out the project you are currently working on. In case you wish to print the whole disk, I have split it up into sections so that it does not become too tedious.
Robert A. Wilson F.R.S.A.
Sample page at much reduced size and quality