Technical pages :
Quelques réflexions sur la super-réaction
by C. Maennel.
Super-regeneration has been widely used in the past due to the large gain obtained with a very simple circuit. We try to explain how this system works by analysing the response of a heterodyne oscillator when the coupling between anode and grid is progressively increased. The system acts first as a grid detector for zero coupling, then as a regenerative detector, third as a sine oscillator and finally as super-regeneration, which is similar to a blocking oscillator. The detected signal is not the amplitude, but the working ratio, which depends logarithmically with the input signal. The result is a very high gain at small signals. Gains between all these are compared.
History of men :
Henri de France
by P. Melusson.
Our friend Pierre Mélusson gave us some interesting documents dug out of his archives accumulated during his service in a big firm. Therefore we are able to convey to our readers some excepts of these records placing one of the talented engineers to whose we are indebted for the great strides they have provided to our favourite techniques.
History of techniques :
La musique mène à tout
by P. Demerseman, R. Foster.
The title "Music is basic" is exemplified by a survey of the various inventions owed to Sir Charles Wheatstone. Nearly always remenbered for the Wheatstone bridge he only contributed to popularize, he carried out munch reseach concerning musical instruments, sound propagation, telegraph, data storage, cyphers, visible light, stereoscopic vision, dynamos etc... Though his diverse studies do not belong to the pure field of wireless, they are often so closely related to that we propose this paper as a contribution to the commemoration of is bicentenary.
Toujours les mini-radios
by J.-C. Montagné.
Following the publication of our 104 and 105 issues, describing two-tubes receivers, here is another wiring diagram published by "Wireless World" in its March 1955 issue, after R.C. Lever and reprinted by "toute la Radio" in 1956 in an adaptation to French customers.
Musées insolites : le musée du train et du jouet et le musée 1900
by P. Demerseman.
Comment fabriquer des piles au bichromate alcalin
by E. Divert.
Many collectors enjoy the possession of dichromate batteries and don't know the better way to use them. Hereafter is reproduced an article published in 1931, when the users knew the good methods to put the batteries into service.