Ivory sheets :
Poste Philips IC2000
Un des premiers récepteurs radio commercialisé en Europe avec des circuits intégrés.
Un sauvetage typique
by Gérard Tourtonde.
Un Ducretet D436
This is the story of the restoration of a receiver which, at first sight, didn’t deserve to be repaired. It had spent nearly forty years in an unheated, humid basement, it’s external appearance was offputting and it’s chassis quite rusty. Nobody would have paid a penny for it at a flea market, and yet I got it working quite well again for next to nothing. Moreover, the steps followed in its restoration are fairly typical for such cases: after fixing some major faults, usually easily pinpointed, you then spend a lot of time dealing with lesser, often intermittent, problems…
Réparation des boîtiers en plastique
by Pierre Rouaud.
Personally I really like the small hexagonal Philips or Radiola sets. These can be found quite readily at flea markets. On the other hand their cases are fragile and it’s much harder to find them in good condition.
Here is how to repair them.
Dépannage d'un oscilloscope Hameg HM 203-6
by Didier Meignant.
I recently found at a flea market a HAMEG HM 203-6 oscilloscope in perfect cosmetic condition (figure 1) and the seller assured me it was in working order. I had my doubts however, given the paltry price (25 €), but told myself that at this price, even if it was out of service, I would enjoy repairing it. It’s a 20MHz bandwidth dual channel analogue ‘scope with no frills (such as delayed timebase…).
Technical pages :
L’Électronicofil s’initie au filtrage actif transistorisé
by Gérard Prieur.
When using silicon diodes in place of valves a larger ballast/filter capacitor can be used, and that way increase the rectified voltage whilst decreasing the residual ripple. It is tempting, in this case, to try and go even further by using a semiconductor active filter. This process is implemented here using recycled bipolar silicon transistors (from old 20th century colour TVs).
Rejoignez le monde de l’Arduino en construisant un générateur HF/BF
by Daniel Maignan.
In this edition, we look at the second part of the article on the AD9850 DDS generator, which is primarily dedicated to the practical side of its construction and implementation.
Note that you don’t have to adhere to these instructions 100% but, beyond its programming, it is nevertheless an electronic assembly so the wiring of the core components — AD9850/ Arduino — must be rigorously followed.
Un amplificateur de 2 watts pour radiodiffusion en AM
by Daniel Maignan.
After the disappearance of French stations transmitting on medium wave (MW), then on long wave (LW), with the cessation of broadcasting by France Inter from the Allouis transmitter at the end of 1996 and then, at the beginning of this year, Europe 1 which ceased its transmissions, it is now the turn of RMC which stopped broadcasting on 27th March.
All that’s left on long wave is RTL, the BBC and Radio Alger, as well as the Spanish transmitters on MW in the evening (with associated fading).
As in another area where this has led to a major catastrophe, the policy of cost-cutting, brutal and lacking foresight, is happening in the field of radio.
At Radio France, with about six hundred FM transmitters, France Inter provides coverage to about 96% of the population. The audiovisual reform, geared towards the drastic cutting of budgets, has led to the desertion of Long and Medium waves, with no regard for either the 4% who don’t receive FM or for foreign listeners.
Public Service, a word that doesn’t mean much any more.
It’s the end of our glorious regional stations of the 60’s and designing or building an AM transmitter will unfortunately soon be the only way to listen to our Vintage wireless sets and other transistor radios.
That’s why I introduce here the full description of an experimental linear amplifier with enough power to allow you to listen to them comfortably, by means of a lab generator (as long as it has an external modulation input), the Arduino/AF9850 generator or other transmitters published in this magazine.
It should be noted, however, that the use of this experimental amplifier can only be done as a test, under the full responsibility of the experimenter, who is recommended to contact the CSA and the ANFR (or equivalents in the experimenter’s country) for any information.
Visite chez un collectionneur des Hautes-Pyrénées
Francis Louvion RFL-579 réside à Saléchan, un petit village d’Occitanie de quelques centaines d’habitants qui se situe près de la frontière espagnole. La commune a le privilège de se trouver à proximité du Parc naturel régional des Pyrénées ariègeoises.
Réalisation d'un lampemètre : le LDD01
by Daniel Werbrouck.
It all started with a simple observation that is probably common to a few “ radiofilistes “. Over the last few decades, I have amassed a stock of valves which I now realise a second lifetime would not be enough to use even a quarter of them… What can I do ?? After a preliminary visual screening, to weed out the valves with missing and/or illegible markings, how do I determine the state of the remaining « treasure » ?
The goal is set: to please friends, sell a few rare types, donate the more common ones to the club and eliminate those which don’t measure up to spec. In short, do enough to make room in the workshop and fulfil some of the requests from those desperate to restore their Vintage wireless sets and amplifiers. But to avoid offering questionable gifts, it would seem to be essential to check the condition of each valve.
If we’ve all dreamed of one day owning a Metrix 310B, U61C (or D) or even the super LX109 valve tester, as much out of nostalgia as performance, in 2020, we must still put the fantasy into perspective… At least three reasons brought me back down to earth. First: the size of the Metrix beast does not correspond with the notion of making more space in my workshop. Second: the rarity, and therefore price, of this type of gear makes it non cost-effective – between 300 and 800 Euro depending on model and condition. Third: you don’t use a valve tester often and it would be much more practical to have something easily transportable so that friends could have the benefit of it without involving a removal company…