FTM Heft 11/12 1942
by Reinhard Kretzmann
pages 157 - 160
Standardisation (design) of Luftwaffe (GAF) valve (tube) base and sockets
This project was, however, meant for the electronics industry as a whole
German language PDF
This article is, however, also interesting for non German speakers. As it shows how the Germans have ultimately rationalized their electronic apparatus design
Far down is shown some typical samples belonging to our valve collections
I believe, that the post-war Rimlock valve series have something in common with the valve envelope of a LV9. Of course, these types had to be fit in German standardized base, but its general design allowed very easy adoption to another base-type
LV9, a battery pentode
LV3 and LV13 Preßteller = Socket/base type D**
The valve (tube) height can be adjusted for various valve types. What was changed (adjusted) was the extender between the main holder and ceramic socket plate. Please notice the off-setting of the anode pins, which allowed minimal coupling between in- and output. This is very significant, as the bandwidth of a valve stage is determined by the ratio between Cag and S (= g mutual conductance). A closed top-lid of this valve base secured that even under heavy shock conditions the valve was locked-up safely in it.
The basic patent to this ceramic socket(base) is: DE762245#
The Russians adopted this valve design (philosophy) for quite a long time (decades)!
LD15 and its ceramic socket with valve holder
The aluminium block on top of this valve was mainly used for glass-envelope cooling, secondly it provided a way to pull the valve out of its socket. It also secured that the valve was kept centred when it was being pushed(placed) in position
Must be base Preßteller type F**
This was the transmitter valve of Lichtenstein SN2 (push-pull stage)
It can be noticed, that the Germans took considerable care to keep the (internal) lead inductance as low as possible
LG200 thyratron used in Siemens radar FuG218
Must be Preßteller (base) type E**
Made by Valvo, which was a subsidiary of Philips in the Netherlands
The LG200 as LG6 were both designed and made by Valvo (Hamburg)
Noticeable is, that all pin-socket-connectors (contacts) were made very accurately and were of high quality material (Kontrazit-Beryllium-Bronze, see page 159)
**It is likely, that in the text at pages 158/160 sizes on the socket/envelope are not given correctly, as base D should have 25 mm diameter, whereas the valve shown has at least a diameter of 38/39 mm. Also the LG10 shown is much bigger than 35 mm, as it actually is: 60 mm.
All this might originate from wartime security reasons
However, the provided details are still interesting!
#This patent document is very curious, as it differs totally from regular patent files. What is shown is, the original application forms. Including all changes and showing the way in which the granting procedure went. We can see, as is also explained in my patent dBase section, that the Third Reich took over these patent claims. These kinds of documents were considered in 1945-1950 being a trophy of war and were shipped to the US. There they kept it for decades. In the late 1970s maybe 1990s these papers returned back to the German Patent Office. When they started to make patent files available on the web, they did not care for these odd files. But since their work was finished, they decided to fill-in the gap of lost patent documents. But, because these documents were already obsolete, they decided to put them as they are on the web. Curious is, that they do not appear in regular patent dBases. Only by pure coincidence, I discovered their existence (The British Patent Computer broke down and a staff member told me: that I should try depatisnet. And, it was 'bingo'! Now all (many thousands) lost files are becoming available. I myself have marked these with the extension 'ap', which stands for 'application' and that is what it actually is! (See my 'patent DE' dBase). Please notice, that not yet all have been entered into our Patent DE dBase, but will be done, in due course (Deo volente, Spring 2008)
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