Forschungsstelle Langeveld

a Survey


It is documented that the German Reichspost (equalling more or less the British GPO)

managed  to intercept Britain's secret (strategic) wireless telephone link,

between London and Washington.


First: Hans Knap

wrote a book in Dutch language about this subject (1998).

"Forschungsstelle Langeveld

Duits afluisterstation in bezet Nederland"

It has to be noticed though, that he has brought some (interesting) information to daylight.

But, he didn't really grasped

what the employed technologies were about.

Just slightly earlier:

Günther W. Gellermann

published his: "...und lauschten für Hitler"

This book is in some way better documented.

But neither, Hans Knap nor Günther Gellermann

have got access, to the sources available since the turn of this century;

which successively have been made public during, say: 1999 ... 2011;

by the British National Archives.

(Please notice also: that my additional comments can always be recognised - by the application of blue or red colour writings)



Status: 2 October 2020


1 + 2 + 3 + 3a + 4




Considering first ranges of KV 2/ serials,  I encountered



                                                                                                                                                                                        Crown Copyright

KV 2/954-2, page 16

Please notice first: CX 12650/2405?    From experience, I know this is pointing at M.I.6 material, and the serial-range 12xxx is mainly pointing at Germany related subjects.



    With reference to D.S. Doc report No 1934 of 8 July (1945) on Dr. Hans Thost, we have received a request for further details regarding the tapping of telephone conversations between England and America.

    If Thost is still available for interrogation, perhaps he could be asked:-


        i)      How many different circuits (lines) the telephone experts actually intercepted or tried to intercept.

        ii)     What were the source of each telephone circuit (line or connection) and how many conversations on each were intercepted?

        iii)    Whether they were aware of the existence of any other channel of telephone communication between this country and abroad, apart from those which were actually intercepted.

        If     Thost is unable to answer these questions, they might with advantage also be put to Dr. Paeffgen (Päffgen) (The latter was once Leiter of the entire Amt VI D sections)

(AOB, don't worry, Dr. Thost possessed quite a good memory!)


                                                                                                                                                                                                     Crown Copyright

KV 2/954-2, page 17


First detailed interrogation Report.

(AOB, it was apparent, that quite many "higher ups" were kept in captivity for a considerable time  -  after the end of the hostilities in Western Europe, in May 1945)


  •     Source        :  Thost, Dr. Hans Wilhelm


  •     Position      :  Author and Propaganda agent. (AOB, his expertise was English language; and not propaganda!)                                                                                  


  •     Case No.    :  S020/USDIC/DC6


  •     Date           :  3 January 1946


                    This report contains information on the activities of Dr. Hans Wilhelm Thost in connection with Amt VI during the war.

On page 18 we learn:    That he had been engaged at the Dolmetscher Bereitschaftsdienst.

A.    Assignment in Translation (English German or reverse)

quoting partly from page 19:    The "Dolmetscher Bereitschaftsdienst".

    When the war broke out Source (Dr. Hans Thost) was an independent writer living in Berlin, Gruenewald.  He had just finished his book "Als Nationalsozialist in England", which in some ways was opposed to the official foreign policy of Ribbentrop (The German Foreign Affairs Minister). Financially, Source (Thost) was independent because of his real estate in Leipzig.

    because he was severely wounded at the end of World War I (1914-1918), he was not fit for front line duty again. He expected the war to be over  soon and did not care to change his personal status.


A.    Assignment in Translation

    Source (Thost) did not hear anything more about the questionnaire (AOB, skipped) throughout 1940, but in February 1941 he was visited by an SS officer, Hauptsturmführer (Hptm, or Captain) Zuchristian, who inquired whether Source (Thost) would be prepared to do some translation work for his office. which he said was some sort of political information institute. Source agreed and Zuchristian left him many London newspapers, telling him to read them through and pointing out the articles of interest.

Quoting from page 20:

    As ordered, Source (Thost) brought this report and the papers to Zuchristian's office Berkaerstrasse (pronounce: Berka-erstrasse) 32 - 35 (36 maybe also 38) and the work was favourably received. ...




The long stretched building constituted the Headquarters of Amt VI, at the Berkaerstrasse (32 - 36 or even 38)

The quadratic white building adjacent on the right-hand side (from our perspective), was to what I have learned - a bomb-shelter, where the personnel and archives could be kept in safety.



                                                                                                                                                                                                                         Crown Copyright

KV 2/954-2, page 24


Page 24:

G. Interception of Wireless Conversations.

   1.Intercepting Station in Operation.

            One day in the winter of 1942-1943 Source (Dr. Thost) was called to the office of Dr. Päffgen (Head of Amt VI D) and introduced to a Dr. vetterlein, high technical official of the “Forschungsamt der Deutschen Reichspost “(scientific laboratory of the German Post), who stated that he had already spoken with Schellenberg and that he had an offer to make to Päffgen and Source (Dr. Thost, who had once lived for many years in England). Also present at the meeting was Dr. Schueddekopf  (; and [KV 2/2646- 2648]) (he also was, for some time, stationed in the office of the Embassy (Police section). (Dipl.-ing.)Vetterlein showed them some some messages which he said he had been able to intercept from the conversations between Washington and London.  A station was situated in Holland near Eindhoven. (They first settled at Langeveld near to Noordwijk in the Dutch PTT reception centre known as NORA (Noordwijk Radio); Their main technical barrack was code-named: “Dünenarche”. To what I understood: the reason of moving more inland wards, was for safety precautions, as NORA was situated rather near to the the North Sea beach) (I have, however found in Hans Knap's book a document reference 26 February 1943, and by then the endeavour was still situated at the Nora premises [Hans Knap page 263]). Ohnesorge, the German Minister for Post, would be greatly interested in this matter and would be prepared to spend millions on that station if it could be of any use to the department.  Vetterlein added that Ohnesorge was reluctant to offer the results of the station to the Military because he distrusted them, especially the head of the German Communication troops , a General who later participated in the July 20th Putsch (General Erich Fellgiebel). Vetterlein asked them to read through these samples of picked-up messages and to decide whether the would want them or not.  The matter, he said, would be of great future value, as the Ministry for Post was prepared to spend large sums on its development provided it was thought to be worthwhile.  He added that there was even the possibility of listening in on messages between England and the U.S.A. just by putting a U-Boat near these cables. Of that prospect they never heard anything more.


            Source (Dr. Thost) opined that everything which could help in a major war was worth trying.  The samples were obviously conversations between officials in London and Washington, but many words were missing and the whole content did not make sense at the first glance (look). Schueddekopf [KV 2/2646 - KV 2/2648] was more sceptical about the matter, but Päffgen agreed with Source (Dr. Thost) saying that improvement on the technical side and schooling of the personnel would result in receiving these pickups clearly.  Päffgen, as chief of Amt VI D had the least word in the matter and decided in the affirmative (agreeing). Consequently Vetterlein immediately returned to Eindhoven to start work. (or was it Langeveld near to Noordwijk?)


            2.Conversation between London and Washington.


                After some weeks the first results arrived; they were, as a whole, not too discouraging. The telephone number in Washington was Republic 2020.


Dipl.-ing. Vetterlein, photo taken ca. 1947


                                                                                                                                                                                                 Crown Copyright

KV 2/954-2, page 25


p.25:    Between War Office, and British Army Staff, Washington.

            Sometimes the British Ministry of Supply was on the London end of the phone  instead of the War Office. General Macready, head of the BAS in Washington: did not speak himself; most of the the time the speaker was Brigadier Leslie Dawes and in London, Brigadier Owen Young.  Frequently the officer in London spoke the War Office line and a couple of days later from the Ministry of Supply line establishing the fact that the links between the ministries were very close.  The contents of the conversations were obviously cover names for the items which they spoke about, such as “grapefruits”, “pineapples”, etc.  It was evident that the speakers on that wireless telephone were aware of the possibility that their conversations might be intercepted. Sometimes they warned each other by saying: “Send ma a cable about that, don’t mention it on the telephone”.


            (b)   Between the Ministry of War Transport, London, and British Shipping Mission, Washington.

            The talks were about the distribution of the ordinary shipping space.  The speakers used cover names for the theatre of war the ships were allocated to.  For instance, the Washington representative of the Ministry of War Transport informed his colleague in London that he had to take 54 ships from “Arthur’s place” (Pacific?)  to “John’s place”, that the situation was “fairly critical”, etc. On the German side, they could not read these messages like an open book, but certain general conclusions could be drawn if they got enough of these conversations/  There was no possibility of drawing actual conclusions as to ship movements which could be of direct value to U-boat warfare although a vague general picture of the shipping disposition on the Allied side was obtained.


            (c)   Between Ministry of War Transportation, London, and Representative of Same in Washington.


            These talks were about tanker allocations. Since the names of the men on the telephone were disclosed by the telephone operators, Source (Thost) had only to look up the “Whitacker” reference book to see in which department of the Ministry of War Transport the speaking official was working.  This book also helped to find out which ministry was speaking because the Washington and the London telephone numbers were announced by the operators, “Whitacker” mentioned all the telephone numbers of the Ministries, Embassies, etc.



                                                                                                                                                                                             Crown Copyright

KV 2/954-2, page 26



Page 26:          The “tanker calls” were by far the most frequent and interesting ones.  The impression of Source (Thost) and his superior was that the lack of tanker space was the weakest point of the Allies. Frequently tankers, once up to 70 ships had to be taken from one theatre to another, and there seemed to be a lot of difference of the opinions as to the allocation of this type of tonnage.

Page 26:          These talks were of decided military value and therefore did not belong to Amt VI, but to Military Intelligence. Päffgen was reluctant to send the messages directly to the Oberkommando der Wehrmacht (OKW). He stated that the possession of these messages was a most secret affair and could not even be disclosed to the OKW. (AOB, in my perception a truly wise point of view). He ordered Source (Thost)  to work out short reports concerning these pick-ups which he would forward out of short reports concerning these pick-ups which would be forwarded to the OKW.  These reports were to be written in a form that the reader could not draw the conclusion where or how this information was gained. This, of course, was impossible to do. Source (Thost), without having had any military or naval training, could not find out the real the real names in place of the cover names, but the trained people at OKW, and especially the naval people with all their information might have been able to use these pick-ups to great value.  Source (Thost) told Paeffgen (Päffgen) of the neglect and begged him to consult Schellenberg (Leiter Amt VI)  again on the matter. Finally it was decided that these calls should be sent directly to the OKW without Source (Thost) doing more than reading them through and passing them on. Source usually passed them on to Obstlt. Engelhorn ( I H?) (who was executed because of his participation in the 20 July Putsch) and later to Korvetten-Kapitän von Redl (from Vienna) of Amt Mil B.  (AOB, I would like to omit - to explain the difference between Amt VI and the Mil/Amt)


p. 26: (d)  Calls Relating to Political and Diplomatic Matters.

            Discussions between the British Embassy in Washington and the Foreign Office in London were for the part cleverly camouflaged, although at times interesting  features could be concluded from them.  It was learned, for instance, that certain discussions took place between the Allies and that Britain would act as the chief speaker for the American-British side towards the Russians.  The subject of these discussions was not definitely known, but from certain hints and newspaper and radio announcements, the conclusion was drawn that the topic was “the oil supplies of Iraq and Iran”.  More and more it was concluded that these pick-ups were most valuable if combined with all other sources of information, especially newspapers, radio and other ‘open’ news.



                                                                                                                                                                                                     Crown Copyright

KV 2/954-2, page 27


Page 27:  Other purely political conversations took place between various Allied government representatives. The Dutch Government in London telephoned frequently to his representatives in Washington, and once or twice the station overheard conversations between the Russian Ambassador in Washington and Mr. Maisky’s Embassy in London. In this case the Allied operator had to admonish the speakers frequently not to speak Russian but English.

Several times the conversation between Churchill and Eden, who was in Washington, were picked up. Churchill usually spoke under the name of his secretary or was simply called “Captain”, but it was not difficult to disclose his identity. The contents of these conversations were not of high political significance but certain conclusions could be drawn out of the general atmosphere in which they were conducted.


            These frequent conversations could be used by this office as fitting in ‘material to their other information/ Sometimes the mere temper of the [persons speaking allowed conclusions to be drawn as to the progress of certain negotiations between the Allies. For example:  Eden once spoke to one of his Foreign Office secretaries in London in a terrible rage (fury, anger).  He called him a “silly ass” and “idiot”, and it was evident that something went wrong on the other side.


      (e)  Calls relating to Economic Matters.

            As the war was nearing its end, economic matters seemed to gain the upper hand in these Washington and London calls.

(AOB, this implies: that the organisation, operated for a considerable time span!)


            The conversations between the State department, Washington, and the U.S. Embassy in London were mostly conducted by FEA (Foreign Economic Administration) people, who telephoned quite openly about locomoptives to be delivered to the French after the invasion and about the help of American engineers and equipment for British mining industry.


            When Governor Lehman was in London in 1944, he phoned frequently to Washington on behalf of the UNRRA and it was heard that the Cairo office of that organization got into trouble by buying clothes on the black market instead of waiting for cheaper ones coming from the U.S. Shipping difficulties were frequently mentioned as hampering the war effort of the UNRRA, and there were differences of opinion between the UNRRA authorities and the Tito Government, which wanted to have all the goods distributed under its own name.


                                                                                                                                                                                                     Crown Copyright

KV 2/954-2, page 28

Page 28

            All news gathered from these pick-ups were allocated by Source (Dr. Thost) to various departments of VI; he sent the economic ones to VI Wi and Tech.


H.   Description of Pick-up Station.

  1.   Dr. Thost’s Visit to Eindhoven.


In August 1944 Source (Thost) was ordered to pay a visit to the listening station (south of Eindhoven, Holland), to hear some new proposals made by Dr. Vetterlein.  This station was situated in a villa, and the entire technical installation consisting of an outfit (the dimensions of which were surprising) was located in the bomb proof cellar. The equipment filled at least three large rooms from top to bottom.  On the outside surrounding the villa there were about six transmission (receiving mast or dipoles?) poles. 

2.   Technical Details of Station.


            Vetterlein showed the entire technical equipment. Source (Thost) gathered that the interception of the radio-telephone conversations (r-t-c) was only possible because Eindhoven was especially suitable from a geographical point of view, being nearly in a straight line with Washington and London. Therefore, Washington was better heard in Eindhoven than in London, because the London voice went around the world (globe) before being picked up in Eindhoven.


            The voices were split by a special ciphering apparatus, (Analpiergerät? and Quarzschaltgerät für Schlüsselwechsel; der Filter etc.) (Gellermann, Sie lauschten für Hitler, S. VI – XII), the high waves being bent (reversed) into low waves and vice versa (de-scrambling), so that ordinary listening resulted in nothing but a squeezing noise.  The American-British used, as far as Source (Dr. Thost) remembers, five different ciphers changing every twelve seconds and practically the same machined had to be installed in the German station with a clock going exactly at the same speed as Greenwich time (see Gellermann, p. XI, down; good visible). These deciphering machines made the voices audible in a microphone (what was spoken from each side at once) as well as head receivers (phones).


            All the talks were recorded on gramophone records and sent up to a lady typist. After typing, the talks were translated into English (German) headed by Mss Mary Honcamp, in 1942) (Gellermann, S. IX) and sent by a special taper (Geheimschreiber) directly to Berlin into the tapper centre of the SS and the “SS Hauptamt” (RSHA), from where the were sent from where they were sent messages to the Berkaerstrasse (pronounce: Berka-erstrasse) (AMT VI / Mil Amt) into Source’s (Dr. Thost) office. These were secret; all the letters were changed so that interception of the line was impossible (operating G-Schreiber).  Source received the r-t-c in English marked as “Geheime Reichssache” and did the allocation according to the contents.


Reconsidering the foregoing explications; let us therefore consider what their technical outfits were:


                                                                                                                                                                                                                          Archive Gellermann

The so-called Koomans multi-channel SSB receivers, were available at Nora;  Nora or as the Germans designated it: Forschungsstelle Langeveld

these were employed until the Germans invaded The Netherlands and the Dutch Forces surrendered on 15th May 1940 to the Germans. 




This is our genuine multi-channel Koomans SSB receiver (photo taken in our archives under construction, in 2004) (three racks measuring together ca. 3 metres)

We obtained it about 1999, via former PTT channels, thus it had before never been in private hands.

Also employed by the former Dutch PTT in their intercontinental wireless telephone links.

Providing: four (4) SSB channels (two at lower-sideband - LSB) and (two at upper-sidebands - USB) all parallel, though of different off-set spectra - from the (virtually) suppressed signal carrier; two voice and two telegraphy channels (in some occasions even employing diversity for telex)

The middle- and right-hand units contained the higher- spectra filters.

Before we installed it at its current place in 2004, I removed each module first; and checked it for signs of date-stamps.

I encountered 3 dates:

1940     No proof, because it could have been repaired or otherwise, before the German Armies invaded the Netherlands, on 10 May 1940.

1943!    In my perception, this should, most likely, pointing at a wartime application. Please bear in mind: that all wireless-telephone-links had ceased, since 15 May 1940!  Our system, must - from the point of specifications equalling the sets shown on the photo from Gellermann. There even might have been a chance that our set was once used at the Eindhoven site; or (also) at Nora.

1948    The Germans surrendered in May 1945. But the Dutch Government - tried to rule, still, in Dutch-East-Indies, now known as Indonesia. They were engaged in a tough colonial war against Indonesians fighting for their independence, since 17 August 1945).  In those (colonial) days - telephoning with Batavia (Djakarta/Jakarta) up (at least) to the end of 1949 was most likely maintained. Why not using gear available (at hand)?



For those interested in the receiver concept, enjoy the above block-diagram

                                                                                                                     Research:  Onderzoek en ontwikkeling bij KPN; D. van de Nieuwe Giessen; page 77

Block diagram of the multi-channel SSB Koomans receiver concept of 1937



But what kind of techniques had been maintained, by the Germans?


                                                                                                                                                                                                                                Archive Gellermann

The core of the entire endeavour was; viewed from left to right:

Analpiergerät, the Quartz-clock controlled programmable switches and likely next the filter-banks to and right of it the following electronics. Maybe also containing the 6 different scrambler demodulators.

I suppose: that they dealt with 5 frequency (spectrum) ranges.  Count yourself the boxes adjacent to the quartz-clock.

Right of it we notice five shelves with Philips type tone generator (sources) GM 2308 (also known as the "Blokfluit" as it was created by ir. Blok (Block?) of Philips Natlab.)  These well known generators might have provided the various descambling frequencies.

The quartz controlled clock was controlling the exact sequence of the 12 seconds mode switching.

The German cover-name of the barrack was: "Dünenarche".



one gets from the interrogation of Dr. Hans Wilhelm Thost - that it was a development of, say, 1944.

But this isn't according the very facts, as The Reichspostminister Ohnesorge, already wrote Hitler, on 6. March 1942:




Knap page 229

Quoting Gellermann's and Hans Knap's book:

            Mein Führer!

        Die Forschungsanstalt der Deutschen Reichspost hat als neueste ihrer Arbeiten eine Ablauscheinrichtung für den mit allen Mitteln modernster Nachrichtentechnik unverständlich gemachten Fernsprechverkehr zwischen den USA und England fertiggebracht. Dank der hingabevollen Arbeit ihrer Wissenschaftler ist es ihr als einziger Stelle Deutschlands gelungen, das mit allen Mitteln unverständlich gemachte Sprachgemisch im Augenblick der Aufnahme wieder verständlich zu machen ...

    Die Ergebnisse unserer Aufnahmen werde ich and den Reichsfüher SS. Pg (Parteigenosse) Himmler, weiterleiten, der sich vom 22. März laufend vorlegen wird. ???  (AOB, this could have been the earliest moment that Dr. Thost became involved).

        Diese unmittelbare Vorlage halte ich im Interesse der Sache für geboten, da schon die Tatsache des Erfolges beim Bekanntwerden den Engänder zur Aufnahme des Fernsprechverkehrs und zum Übergang auf die Telegraphenkabel veranlassen könnte.


An den

Führer und Reichskanzler

des Großdeutschen Reiches

Berlin W 8

                                                                                                                                                                                                                            signed by: Ohnesorge




                                                                                                                                                                                                     Crown Copyright

KV 2/954-2, page 29


Page 29

3.  Dr. Vetterlein’s Proposals.


            Source (Dr. Thost of Amt VI D) stayed at this station about three days, during the course of which he and Vetterlein thoroughly discussed the r-t-c’s.  Vetterlein explained the various technical installations, not yet fully developed through which other types of radio messages coming from America and British newspaper representatives to their respective editors in London and New York.  They did not disclose many secrets but served Amt VI in respective ‘open’ news much earlier than hitherto.  Secondly, ciphered news was picked up and hidden in so-called five letter ciphers which had to be deciphered.  Source thought it worthwhile to receive these pick-ups as well. Vetterlein stated that this extension of duties in his pick-up station meant more personnel and still more extensive machinery, although he, too, thought matter worthwhile. Both agreed that the best thing to do would be to have a permanent representative of Amt VI in this station, a person who knew the value of various pick-ups and one who could decide on the spot whether or not an intercepted t-t-c should be sent to Source (Dr. Thost) in Berlin.  Source (Dr. Thost) thought of training one of their lady secretaries and then sending her permanently to Eindhoven. Regarding the cost of the technical extensions, Vetterlein undertook to ask his Ministry of Post people for the money (RPZ), and Source (Dr. Thost) tried to persuade Schellenberg to write a letter to Ohnesorge (Minister/Director of the RPZ), confirming that these investments would be of value for the conduct of the war.


            Upon Source’s (Dr. Thost’s) return to Berlin the progress of the Allied invasion brought the whole scheme to an end. (AOB, say August 1944) Vetterlein succeeded in getting all his equipment out of Holland and subsequently attempted to resettle with his station on the Sieg river, but his t-t-c’s slowly faded away. The last ones Source (Dr. Thost) as late January 1945, but irregularly and with frequent interruptions. As the whole German communication system slowly became disorganized, the same implications arose with the r-t-c’s.



Let us today have a brief view in what the technology was about:



 Gellermann page 286

I would first like to point: that Gellermann's principle schematic, is considering 6 filter banks (sections), but according to the foregoing photo ( clearly shows 5 filter banks.

The shown spectrum in Abb. 1, is not reflecting the actual distribution of human speech spectra; which are, generally, in the western world: ca. 300 - 3000 (3400) Hz. But telephones in the 1930s weren't transmitting a spectrum surpassing 2400 à 2700 Hz; or not even that spectrum.

The curves possessing an inversed slope as what has been drawn at Abb.1, should be considered of having a reversed sideband modulation. For decades, this "vocoder" principle was already state of the art  -even before the start of   WW II.   But the real break-through was - that the Germans could, more or less, instantly copeing with the actual coding sequences employed on the Allied side; hence real-time.


I would like, Deo volente, to show (quoting) you some examples of decoded interceptions of telephone conversations - held between Churchill and Roosevelt in 1942.  





On: 12 September 2020


We have already been informed, that the RSHA (Reichssicherheitshauptamt) was the main addressee concerning the Forschungsstelle Langeveld - and later the Eindhoven intercepts.


When Himmler visited  the Netherlands - between 16 and 20 Mai 1942


                                                                                                                                                                                Der Dienstkalender Heinrich Himmlers

Also a visit was scheduled:

Quoting:  10.00:    Abfahr in Gegend Haarlem, Besichtigung einer Tulpenzucht und einer Forschungsanstalt der RP (Reichspost)

AOB: In my perception, reflecting the significance of what officially, by then, was known as: Forschungsstelle Langeveld   




Somewhere in this vicinity once was about situated the "Forschungsstelle Langeveld"




It proves today no longer possible to locate by means of modern maps to find the spot where Nora and Langeveld, once was situated



Next, is shown an official Dutch pre-war map; please compare the foregoing two GoogleEarth maps and the genuine map below.


Next map_C

                                                                                                                                                                                                                Hans Knap page 158

Curious is, that on the map we encounter Langeveld and Langefeld

Please notice: the smaller circle shows the antennae and receiving site Nora; the bigger circle indicates the the former PTT-Hulplaboratorium and the later required by the youth hotel Duinark.



Hans Goulooze did just send me what he had traced on the web:


Derived from:

This hyperlink enables you, to get an impression of what the antennae were about; among many other related aspects.

I have selected, in particular, this photo - because we encounter 6 controls, versus the 5 filter-banks, apparently employed when the Photo_A was taken at Dünenarche (at Forschungsstelle Langeveld)

In contrast to Gellermann's  Drawing_G showing an example of the application of 6 filter-banks.

The current aim of this contribution, is, to lift some of the existing queries.

My approach, this time, is to employ the sources, currently, at hand.

Therefore, this contribution doesn't claim to unravel this mysterious episode entirely.



On: 14 September 2020






                                                                                                                                                                                                                                                        Knap page 187  

                                                                        Der Leiter der Deutschen

                                                                        Dienstpost in den besetzten

                                                                        niederländischen Gebieten                                                       Den  Haag, den                 15. April 1941

                                                                                                                                                                                Kortenaerkade 12

                                                                                                                                                                                Fernsprecher 180800           

                                                                    II kü  2 5010 Bfd Nr. 3193/41  


                                                                               den Herrn Generaldirektor der PTT

                                                                                im Hause

                                                                                Funkempfangsanlage in Langeveld

                                                                                                                                Da für meine Dienste die kleine Baracke ("Dünenarche") der PTT

                                                                                                                        (versuchsempfangsanlage) in Langeveld (please notice the foregoing map) nicht ausreicht,

                                                                                                                        habe ich hierfür die nicht weit hiervon gelegene Jugendherberge "de Duinark" vorgesehen.

                                                                                                                            Ich benötige für meine Zwecke 2 Rhombus - Antennen (most effective directional type, of quite simple construction, but necessitating much space),

                                                                                                                        die an 8 Holzmasten aufzuhängen und über Lecherleitungen (open-parallel wires, above the ground) oder konzentrischen (coaxial) Kabeln mit dem                        

                                                                                                                        Versuchsgebäude  (Jugendherberge) zu verbinden wären.

                                                                                                                              Zur baldigen Durchführung dieser dringlichen Arbeiten bitte ich mit Herrn Postrat Vetterlein (leading technical engineer) in Verbindung zu treten.   

                                                                                                                              Der Nachricht über die Etrledigung sehe ich gern entgegen.

                                                                                                                                                        Abschrift zur gefälligen vorläufigen Kenntnis.

                                                                                                                                                                                    In Vertretung




                                                        das Deutsche Fernmeldeamt

                                                        Den Haag.

                                                        AOB: I have transcribed this document - because we can learn quite much about the condition under which the German occupying forces ordered the Dutch PTT (think of GPO) to fulfil some of the German demands.

Don't think to negative about this. As it was implied in the permission of the military legislation according "The Hague Military Convention" of 1908.

        What can we learn from it?

That the Germans might have had an office somewhere in the building at the PTT Headquarters at Kortenaerkade 12. By the way, when I got my HAM licence in 1961, this building constituted still the Dutch PTT Headquarters, and long beyond, still.

Then: that The Hague, was the only city in The Netherlands, employing already 6 digits telephone-numbers. Amsterdam and Rotterdam, by then, still were operating 5 digit telephone numbers.

An implication of the mutual commitments might have been: that the Dutch PTT was a State enterprise, and likely valid to a trophy of war. I know, on the other hand, that when the German occupational forces demanded material matters from Dutch entities, that they were prepared to pay for it. All according their regulations:  Verwaltungs- und Wirtschafts-Bestimmungen des Wehrmachtsbbefehlshabers in den Niederlanden.

What is also of significance, is, the reference to a so-called Lecher-line (which it actually wasn't) as a Lecher-line is always tuned at a certain wave-length, which in this case would causing problems, because it was selective and a Rhombic antenna is a wide-band arrangement. Thus, we should consider it as being an open line system. Its advantage, is, that open lines possess very little signal (energy) losses. (Knap page 194)


Knap page 194


Technische Dienst der Telegrafie & Telefonie

Directie.  Kortenaerkade 11 

                                                                    Bericht op schrijven van

                                                                    Betreffende Betrift Bombeneinschlag beim Rundfunkamt Nora


                                                                                                den Herrn Beautragten für Post und Fernmeldewesen

                                                                                                zu Händen des Herrn  telegraphen bevollmächtigten.

                                                                                                                                                                                Im Hause.

            's-Gravenhage (= Den Haag)   den 19. April 1941;  Nr. 17434                Dienst Inspecteur van Breen

                                                                                                                        In Anschluss an die Mitteilung des Hernn Inspecteur van Breen vom 15. ds. übermittele ich Ihnen anbei eine Uebersetzung des Berichtes vom Direktor des telegraphenamtes Amsterdam über den Bombenwurf auf das Rundfunkamt Nora am 14. ds.

                                                                                                                                                                                        Der Oberingenieur-Direktor



                                    Quoting:    Betrifft: Bombeneinschlag.

                                                        Den 16. April 1941                                                                                                                                                                                                                                                                                                                                


                                                1.Ich teile Ihnen mit, dass am 14.April d.J. um 14.25 Uhr 7 Bomben über das Gelände Nora abgeworfen wurden.  Vier Bomben schlugen bei einem der eiserne Türme ein, etwa 150 m nördlich des Empfängergebäudes; die übrigen fielen auf den Starnd etwa 250 m nördwestlich des Empfängergebäudes.

                                                2.Persönliche Unfälle kamen nicht vor. Die Beschädigungen der Masten sind nicht ernstlicher Art und können in einfacher Weise wieder hergestellt werden. Eine ziemliche grosse Anzahl Antennen wurde beschädigt.

Vom Empfängergebäude wurde ein fenster zerstört. Die Vermutung dass das Bekleben der Fensterscheiben grössere Glasschaden vermieden hat, erscheint mir nicht ohne Grund.

                                                3.Nachstehend folgt eine Uebersicht der beschädigten und die getroffenen Wiederherstellungsmassnahmen: 

                                                    a.   Das netz mit Trägerkabeln und Abspannungskabel des PMC-beams (Richtstrahler) Seeseite (zwischen den eiserne Tütme hängend) wurde nahezu vollständig zerstört.  In das Eisen eines Fusses des nördlichen Turmes and das dabei stehende Abstannjochs wurden löcher eingeschlagen. Die beschädigten Teile sollen verstärkt bezw. erneuert werden, während das Am=ntennennetz ersetzt werden soll.

                                                    b.   Eine beavarage-Antenne (very particular receiving antenna arrange ment, for very low angle approaching waves) von Nordamerika wurde zerstört. Diese ist bereits durch eine neue ersetzt worden.

                                                    c.   Von Japan-beam wurde das Antennennetz zerstört (bereits wieder hergestellt).

                                                    d.   Eine Rhombusantenne von Nordamerika wurde zerstört (bereits wieder hergestellt).

                                                    e.   Vom OLV-beam (Richtung Ostindien) wurde ein Netz heschädigt (bereits wiederhergestellt).

                                                    f.   Die Rhombus antenne von Südamerika wurde zerstört (bereits wiederhergestellt).

                                                    g.   von einem der Mannesmann-Msten brach eines der Abspannseile (10 m Draht), welches mit der Spitze des Mastens verbunden war. Da diese Beschädigung unverzüglich               wiederhergestellt werdenm musste, wurde noch am selben Tage ein Teil des Aussenpersonals in Tätigkeit gesetzt. Um 18.45 Uhr war das Seolkabel wieder brauchbar. 

                                                                                                                                                                                                                            Der Direktor

                                                                                                                                                                                                                           (w. gez.) Bossen


AOB: why was the position of the Nora site so essential?

The Germans considered the geographical position of Nora versus London and Washington (Long Island by New York) favourable. As its position versus Coolrich (a marsh peninsula adjacent to the Themse-mouth) and the US station being about in a more or less straight line. Dr. Thost pointed, that the Germans received the Coolrich signal after it had nearly pasted around the globe. This would, of course, add a certain additional transit delay; versus the directly received US signal; but which was the consequence of highly directive beaming systems.  Consequently, this technology relied upon highly directive antenna systems. A well designed Rhombus antenna hardly produces rear-ward radiations. Hence, what was heard had circled around the globe firstly!


Knap page 197

Der Befehlshaber der Sicherheitspolizei und des S.D.

für die besetzten niederländischen Gebiete



Wannsee 79  21.4.41

                                                                                                                                                                                        An  Den Haag

                                                                                                                                                                                        An den Befehlshaber der Sipo mit der Bitte um weiterleitung an den Telegraphenbevollmaechtigten

                                                                                                                                                                                        Holland Oberpostrat Kuehlwetter - Ministerium PTT.

                                                                                                                                                                                        Bitte ing. Vetterlein ist zu verständigen, dass geplante aktion nicht durchgeführt werden kann.

                                                                                                                                                                                        Alles andere in Berlin in die Wege geleiet.


                                                                                                                                                                                                                            Gez. Fuhrmann SS-Sturmbannführer


                                                                                                                                                                                                                                  Google Earth 2020

This building was situated at: Am großen Wannsee 74 (Wannsee is the name of the lake, visible);  this building was known as: the "Havelinstitut"

 The house with the red-tiles (corner) roof; constituted the technical and development centre; in particular were wireless communications were concerned.


Knap page 208

In my perception we may learn that the designation: Forschungstelle Langeveld continued to be maintained

The first site was designated Forschungsstelle Langeveld über Noordwijk (AOB, also Nora)

and now after the German group had been moved to the vicinity of Eindhoven we encounter:

Forschungsstelle Langeveld über Eindhoven



Knap's page 255

For some of you - it might be a challenge to fit this aerial-photo in the map_C

Dutch text: RAF aerial-photo taken of Langeveld near to Noorwijk, in March 1945, when already most of the interception gear was moved towards Eindhoven.

An euphemism, because Forschungsstelle Langeveld über Eindhoven had already left the Netherlands, I suppose, in August 1944.


To close this subject, I would like to to quote from a (brief) intercept of a telephone conversation between Churchill and Roosevelt on 7 September 1941, 19.45 German summer-time.

AOB: Please be aware, that: Germany, at that moment, was not yet at war with the United States of America!

Quoting from Gellermann's page 287. AOB: of course, translated into German language. Maybe, you can use Google translate.

A = American President

B = British Prime minister Churchill

Direction A - B Frequenzband vertauschung; according Drawing_G

Direction B - A: Lediglich verlagert und invertiert (AOB, to what I understand: frequency ? shifted and scrambled?)


B:    Hallo, wie geht es Ihnen?   

A:    Wie nett, daß ich ihre Stimme wieder höre.

B:    Sie müssen eine Höllenreise gehabt haben.

A:    Ja, es war sehr scheußlich, ich war sehr verärgert, daß wir in Lissabon 10 Tage aufgehalten wurden, aber es befand sich natürlich jeder in derselben Lage und ich fühlte, daß, wenn der britische Botschafter es ausstehen müßte, ich mir nicht soviel daraus machen dürfe. Aber Sie können es sich denken, daß es ärgerlich war, dort aufgehalten zu werden. Ich glaube, wir müßten alle unsere Leute, besonders die, die wir herüberschicken, warnen, denn sie alle können sonst auch in diese Schwierigkeiten geraten.

B:    Ja.

A:    Wir sollten mehr Leute auf dem Schiffswege reisen lassen, denke ich.

B:    Ja.

A:    Gut, was wir von Ihnen möchten, ist, daß Sie uns bald wie möglich einen Bericht senden, einen Bericht in unserem Sinne, verstehen Sie?!

B:    Ja, eine der Schwierigkeiten wird sein, diesen Bericht hinüberzubekommen. Ich bin mir schon ganz klar, wie ich das mache, aber zweifellos muß es etwas sein, das ganz vertraulich ist, verstehen Sie?!

A:    Ja, ich werde mich auch umsehen müssen, um den besten Weg zu finden.

B:    Gut, ich glaube, daß Sie darin vollkommen Freiheit haben.

A:    Ja, ich werde die Mittel und Wege finden müssen. Was ich aber für nötig erhalte, noch für nötiger als damals, als ich ich in London war, ist, daß wir versuchen müssen, einen erstklassigen Assistenten für Campbell sobald wie möglich zu


B:    (nicht verständlich) (not copied)

     So far my reproduction, as two (Gellermann) book pages are following. My aim, this time, is to show you the way communication between Churchill and Roosevelt commenced; for example.



Today I have contributed related files onto our website; which are related to the subject dealt with on this webpage.

1st: Telefunken's intercontinental telephone SSB system



Siemens Nachrichtentechnik:

Elfter Jahrgang 1941 2.Folge



Those who would like to discuss or to contribute:

Please, type in what you read


Terminated on: 2 October 2020



By Arthur O. Bauer