Jagdschloß A (Jagdschloss A)
German PPI radar system
Technical training manual for radar engineers
Ln Schule 8
Lehrschule für Fernmeldetechnik
2. Auflage (second edition)
Oberkommando der Luftwaffe
Ln.-Inspektion - 6. Abtlg.
All together 317 manuals had been printed
PDF, 4.9 MB
There existed two wave ranges, let us call them respectively A and B: 120 - 157 MHz and 157 - 250 MHz. According to a source, serial production started late 1943. Up to April 1945 were: 18 systems of wave region B and 62 of range A*. Thus, a total number of 80 systems were delivered to the German air defence organisation (Luftwaffe). We don't know exactly how many system became finally operational. *Frequency range A overlapped the regular Freya wave-band.
Die Jagdschloss-Anlagen stammen in ihrer Weiterentwicklung von der Firma Siemens (S&H).
Dies ist die zur Zeit ausgeführte Anlage.
Jagschloss B (geplant) Es bestand von Anfang an der Wunsch, das in einer Gerätestellung gewonnene Luftlagebild an eine zentrale Befehlsstelle zu übertragen. Für die Übertragung des Bildes sind bei der A-Ausführung drei Komponenten erforderlich und zwar ..... (partial text of page 5
Jagdschloss radar antenna-array, seen from the rear. This typical brick-stone building may have been (sometimes) on top of an 'underground bunker'
Keywords: Blockschaltbild Jagdschloss B mit Übertragungseinrichtung; Sternschreiber; Prinzip der Synchronisierung bei Jagdschloss B; Blockschaltbild Jagdschloss A mit Übertragungseinrichtung; Übersichtsskizze Anlage Jagdschloss B; Übersichtskizze Anlage Jagdhaus; Kennung (IFF); Duplexbetrieb; Bildübertragung; Allgem. Meßprinzip der Rundsuchanlagen; Stufenschaltbild der Rundsuchanlage Jagdschloss A; Verdrahtung f. Jagdschloß; Antennen-Anlagen; Aufbau der Antenne; Speisung der Antenne (Kabelplan); Einheitsfeld; Breitbanddipol Ortskurve; Änderung der Strahlungscharakteristik; Kabelplan der Antenne für Jagdschloß; Strahlungsdiagramm; Der Breitbandübertrager; Übertrager 70 Ohm auf 70/2 Ohm; Frequenzgerät; Wirkungsweise; Bedienungsanweisung für Z Gerät; Prüfvorschrift für Z Gerät; Prinzipschaltbid Z-Gerät Phasenschieber (delay line); Zusatzgerät zum Z-Gerät Wirkungsweise Kompl. Scahltbild Zusatzgerät Prüfungsvorschrift; Beobachtungsgerät, Wikungsweise; Im OB-Teil; Prinzipschaltbild Beobachtungsgerät; Gerät R, Einsatz RH101, RN105, RJ102; Prinzipschaltbild R-Gerät; Kompl.Schaltbild Hochtastgerät (20 kV zum Sender); Kompl. Schaltbild Steuerteil; Sender mit TS41; Vorläufige Prüfvorschrift für das Gerät Eibsee mit Gittertastung; Breitband-Simultangerät Rießersee (Riessersee) T/R section; Riessersee 2, Riessersee 3; Prüfvorschrift für Riessersee I, SD6; Der Breitbandempfänger, Technische Angaben, Beschreibung D Zwischenferquenzteiles; EEF50 (EFF 50) at the receiver front-end; EFF50 data sheet; Radar receiver Kreuzeck, Prüfvorschrift für das Gerät Kreuzeck, Bedienungsanweisung; Sternschreiber PPI display unit technical circuit description; Blockschaltbild Sternschreiber; Gleichlaufübertragung, Synchronisierung; Lichtsirene, Photozellenverstärker; Drehstromverstärker; Impulsgerät, Aufgabe, prf 500 Hz, EZ150(double rectifier); Bildwähler, Synchronisierung; Aufbau der Kennungsantenne; HF-Verdahtung des Standes; Antennen-Antrieb; Komplette Röhrenbestückung-Jagdschloß; PPI CRT type LB40 m/3, HR2/100/1,5
Half section of the Jagdschloss antenna array. Its antenna field is horizontally polarized, whereas the vertical radiators in the upper section belong to the IFF system
Fine range measuring set-up of Jagdschloss (Ansicht des Gerätestandes Deckel geöffnet). IFF is the receiver for "Identification Friend or Foo" (code-name "Gemse"), RX is the radar receiver "Kreuzeck", with its front-end (see page 83). RD is the fine-range display CRT, the three clocks on its right indicate mechanically the distance(range) marker (regard also report TME 11-219). Not quite clear, but the magnifying lens had been pulled (fixed) upwards
The PPI display unit (Sternschreiber), cover-plate being removed. The CRT had, presumably, a screen diameter of 40 cm (LB40 m/3)
"Landbriefträger", shown is the carrier interface which was used to transmit radar (video)signals onto remote Command Stations like to an "air-defence operation centre" (Ansicht der Übertagungsanlage). The data was sent via broad-band cable facilities
At the other end of the line was the receiving-end of the radar-data-transmission system, also equipped with a simultaneously operating PPI display (Sternschreiber)
Shown is: the broad-band Jagdschloss transmitter on the right. Left of it is placed the (automatic or simultaneous) "transmit-receive" switch (T/R). This probability maybe an older version
RAF offensive on Berlin with approximately 400 aircraft, on 30 January 1944. The circle constitute the 100 km range marker, the gap in top indicates 'geographical north' (Nordmarke)
Hans Jucker kindly referred to this contribution:
the latest increase of your website, the “Lehrunterlage Jagdschloss A” for the German VHF Surveillance Radarsystem as well as the Technical Manual 11-219 are both very interesting authentic papers for seriously interested fellows in radar history.
Please let me introduce some remarks according the content of the papers:
A former Siemens & Halske representative held a couple of years ago an interesting lecture about the development of the German WWII “Jagdschloss” surveillance radar. He pointed out then, that the basic idea for the plan position representation of radar information (if the slant range and azimuth coordinates of the various targets in the field of view are represented) was borne 1936/37 at the Gema company, Berlin. However, the most restrictive reason for the realization of surveillance radars was the limited performance of the early radar transmitters and receivers.
In opposite to searchlight radars with the typical pencil beam the surveillance radar needs actually a beam that is fanned in the vertical direction, if aircraft are to be observed. So, for a similar power density at the illuminated coverage, the radiated energy must be higher than for the searchlight radar. However the power capability of the Freya transmitters couldn’t be increased without a time consuming new tube program.
Therefore occasionally the development of the “Jagdschloss” Surveillance Radar, Siemens & Halske tried to compensate the insufficient radar performance by an improved receiver. It was planned to use the new Telefunken LV 4 wideband double pentode for the rf preamplifier and the first mixer of the receiver. However, Telefunken had problems with the development of the LV 4 double pentode, so after all Siemens & Halske used the Philips EFF50 for the receiver front end of the “Jagdschloss” surveillance radar. .
The technical manual 11-219 seems to be derived from the original document:
OEMsr 411 - 95 , Survey of German Radar from the Countermeasures Point of View
Originated by the Radio Research Laboratory of the Harvard University, September 4, 1944
operating under Supervision of Office of Scientific Research and Development; National Defense Research Comnittee, Division 15 of Radio Coordination.
It seems to be an updated version of the Document OEMsr 411 – 95 !
I havn’t found before any information that an alternative hard tube modulator (with the RS 323 tube) exist for the FuG 200 Hohentwiel airborne radar ?
My best wishes
I would like to add: That already Chester W. Rice of GE in the US dealt with a PPI like system. And, would like to say: "PPI was alerady in the air:. He described a PPI like radar in 1936, be it without range measuring in the PPI display, as this was read-off a display panel (regard my contribution Radar II.)
In September 2011 we have obtained from the UK the original Jagdschloss transmitter module
Jagdschloss transmitter codename Eibsee
Please consider our: new dedicated transmitter webpage to this transmitter
Prinzipbild - Jagdschloss
Ln.- Ausbildungsstab 2
Zeichnung B/F 231 date 26.7.1944
Please click on this drawing as to open it in pdf
Please notice that you can print the full schematic at a single A4 sheet by using the option in "Acrobat Reader " print what you see at your screen" thus befor doing this adjust the size of the schematic at you computer screen!
List of Jagdschloss codenames (Tarnnamen)
Gemse - IFF receiver. Using 5 x RV12P2000, 1 x LD1 (local oscillator), 1 x RG12D2 (demodulator), 2 x LV1. Gemse was used in all other GAF radar systems as well.
Gh 8a - Amplifier for various controlling pulses. Having 2 x EF14 and 1 x RV12P2000. Two stages though with lacking valve data.
HF-Weiche - The splitting filter, which had to separate the calling transmitter signal at 125 MHz from the FuG25a replying signals at 150 MHz.
Hochtastgerät - High power pulse-modulator having 1 x TS41 driver; and 3 x TS41 in parallel. This power stage generated the 25 kV anode feeding pulse for the transmitter Eibsee. Their anode current is being stepped up by means of the modulator transformer. This maybe a bit more complicate way of doing, but it is increasing system efficiency.
Kreuzeck - The main Jagdschloss receiver. In contrast to regular practice based on Gema technology, Siemens & Halske redesigned many stages and improved also the normal receiver performance. Using now in the front-end 2 times push-pull stages using 2 x EFF50 (thus together 4 x EFF50). Between the two EFF50 push-pull stages the first oscillator signal is being injected (the second push-pull stage is acting as mixer stage; I guess creating a DSB signal). Employing 8 x LV1, a single LV3 used for the broadband video amplifier.
O-Gerät - The main range display using an A-scope presentation. Also being linked with the returning IFF signal (Gemse). The OK unit is the time-base delay-line, by which means the time base is being delayed and the according distance is being read off a direct reading dial (I guess calibrated in 10 or 100 metre steps).
Nordimpulsegenerator - North marker stage, which is keeping the north marker pulse provided by a photocell attached in concert with the rotating Jagdschloss antenna, when it passes compass north. Using 3 x EF14 and 1 x LS50
Phot.Zell.Verstärker - The photo-cell signal amplifier which provided the north marker pulse, bring the top of the PPI screen in concert with the actual antenna position against 'Compass North'. Using 1 x REN901.
Riessersee - T/R stage. Also known as: Simultangerät. Using 2 x SD6 (SD6a). This type was later in the war apparently replaced by so-called Nullodes (Radar News 19)
Sternschreiber - The large screen PPI display. Having 6 x RV12P2000 and 4 x LS50
TSk IFF transmitter - Working with 500 Hz pulses having 2 x LS50 and in the PA 2 x TS41. Consequently, having in this case a much higher transmitting power as it is fed by 2.5 kV anode pulses.
Ü-Gerät - Known as Landbriefträger, including a three phase signal as to synchronise the rotating arc and the antenna rotation. Which also provided signals via broadband telephone line covering the full radar signal including all PPI information towards a remote site. Like Flak bunkers or main air defence control. Please notice the according photo shown previously.
TSo - 500 Hz pulse amplifier consisting of 2 x LS50
Z-Gerät - Time base generator, which provided several time base signals. All having 500 Hz, but with variable phase relation
When we consider the valve types engaged we can see that only LS50s - LV1s - TS41s - EF14s - SD6s and RV12P2000s are being employed (neglecting the single REN901 triode). The advantage is obvious, because service stocks could be kept very rationalised.
Please consider also the new: Jagdschloss TX and system page
Back to or proceed with: Report TME 11-219
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