Description of the radar set, tactical-technical characteristics
Figure 1: “Lichtenstein” display unit
|Specifications of Lichtenstein C-1|
|frequency:||90 MHz (3,3m)|
|pulse repetition time (PRT):||1,1 ms;|
|pulse repetition frequency (PRF):||900 Hz|
|pulsewidth (τ):||1...1,25 µs|
|peak power:||2,5 kW|
|instrumented range:||8 km|
|range resolution:||200 m|
|hits per scan:|
The radar “Lichtenstein- SN 2” (FunkGerät 220, FuG 220) was used to approach targets. Measurements could be made according to distance, altitude and lateral position, which were displayed on two (later three) electron beam tubes. There were two antenna versions: an outer surface antenna and a cockpit antenna. The maximum range was 5 (later 6) kilometers. The bearing accuracy was about 3° in the lateral and elevation angle. The bearing could be taken by electronically swiveling the antenna pattern. A so-called flicker switch switched a bypass line into the antenna feed line at a rate of 25 Hz and fed the antennas in antiphase. Both video signals overlapped in time on the screen. If the target character was displayed large and flicker-free, i.e., the antiphase signal was in the minimum, then the target was exactly in the center.
Other versions were “Lichtenstein-B” (FuG 202) and “Lichtenstein-C1” (FuG 225) with three electron beam tubes and and a large heavy “deer antler antenna”, and as an experimental version the “Lichtenstein-S” (FuG 213) with a pulse power of 30 to 40 kW at a transmit frequency of 150 MHz. The range of the “Lichtenstein-S” was about 30 km.
The display unit with three electron beam tubes had a J-scope for range determination with a scale of 8 km an two A-scopes for displaying bearing and elevation angles.
Other versions, e.g. “Lichtenstein BAUER” FuG 214, were also used as a rear emitting warning device to detect following enemy fighters. For this purpose short Yagi antennas with 4 elements were mounted under the wings, on the right the receiving antenna, on the left the transmitting antenna.
The antennas of the FuG 212 and FuG 220b radios gave the German night fighter Bf 110 G (here as a British prey aircraft) its characteristic appearance.
The keying block (synchronizer) generated strong pulses of about 1 µs duration from 900 Hz sinusoidal oscillation via several transformer-coupled amplifiers and limiters. The transmitter in push-pull mode was modulated with this pulse. The receiver is a superheterodyne and was equipped with nine tubes. The bandwidth was about 1.2 MHz. The oscillator frequency could be retuned with a servo circuit.
The picture tube control contained an oscillating circuit tuned to 75 kHz. During the period of deflection, six oscillations were performed, producing six bright dots on the screen as 2-km marks. The flicker switch was switched by a motor at a rate of 25 Hz. It could be effective with a manually operated antenna switch (not shown in the block diagram) in the bearing angle or in the elevation angle.
Picture gallery of Lichtenstein Radar
Figure 2: Animation: Bearing with
Figure 3: Night fighter Bf 110 G
Figure 4: Block diagram of the Lichtenstein SN2 radar