Direction Finders
Locator Beacons
Emergency Receivers
VHF Radio Direction Finder (VDF) System for ATC and VTS


Vessel Traffic Service (VTS)
Air Traffic Control (ATC)

The RT-1000 VDF system is designed specifically for ATC and VTS applications and complies with ICAO and DFS (Deutsche Flugsicherung) requirements.

The RT-1000 radio direction finder, which has become the benchmark in its class, is also known under the Rohde & Schwarz designation PA030. More than 150 systems are currently in use worldwide.


The RT-1000 VDF is used as an ATC navigation aid that allows controllers on the ground to transmit QDMs to the pilot or verify position reports received from aircraft. Bearing information can also be integrated into a radar screen, which makes it possible to immediately assign radio messages to the right targets on the radar display.

The RT-1000 is also suitable for stationary VTS applications to control the vessel traffic close to the coast.

Special Features

  • High-precision Doppler radio direction finder
  • 8.33 kHz channel spacing in the VHF air band available
  • Extremely high rotation frequency for fast signal processing
  • Compact antenna system for simple installation
  • Antenna location independent of controller workstation
  • No infrastructure required for remote operation
  • Maintenance-friendly modular construction
  • RS-232 interface to permit system integration
  • Frequency range:
    • Aviation band: 118.000 ... 136.975 MHz
    • Marine band: 156.000 ... 174.000 MHz
  • Various scanning modes
  • Two or more simultaneous channels optionally available
  • Multichannel systems up to 24 simultaneous cannels possible


Frequency Range1 118 to 136.975 MHz / 156 to 174 MHz
Operating channels 760 in the airband / 720 in the seaband, 10 channels preselectable
Channel spacing 8.33 kHz2 / 25 kHz
Type of modulation to be detected A3E, F3E, A3X (ELT-modulation)
System accuracy3 ±2° RMS with antenna (±1° with bearing precision improvement option)
Sensitivity4 = 6 µV/m (without antenna amplifier)
Polarisation Vertical
Polarisation error = 1° (with field vector rotation up to 45°)
Cone of silence approx. 35° referred to the vertical
Power supply AC: 115 / 230 V ±15%; 47 ... 63 Hz
DC: 24 V -10% / +20%; automatic switch-over to DC voltage in case of AC mains failure
Power consumption Controller unit: max. 15 VA
Receiver unit: max. 10 VA (52 VA with heater)
Temperature ranges

Operating temperature:
Antenna: -40° ... +80°C
Receiver unit: -40° ... +60°C
Controller unit: -20° ... +55°C

Storage temperature: -40° ... +60°C

Interfaces serial V.24 (RS232)
Bearing display Response time ≤ 0.3 s
Variant A) Digital: 3 digits with 7-segment LED indicator
Resolution: 1°
Bearing reference: QDM, QDR, QUJ, QTE
Updating rate: approx. one indication/s
Variant B)

Dual compass dial: 2 concentrical circles of LED points
Resolution: 10°
Bearing reference: QDR

Updating rate:
Outer circle: approx. one indication/s
Inner circle: 47 indications/s

Monitoring Built-in speaker:
Modulation mode: A3E
Monitor output: approx. 500 mW to 4 ... 8 Ω
Line output: 600 Ω, balanced, 0dBm, m = 0.6
Ground transmitter suppression with external contact to ground
Dimensions / Weight
9"-desk-top model 3 UH, prepared for rack installation
Dimensions (H x W x D): 132.5 x 448 x 370 mm
Weight: 8.1kg

Receiver unit:
Non-metallic cabinet for wall mounting (IP 65)
Dimensions (H x W x D): 250 x 340 x 285 mm
Weight: 6.9kg

Antenna system:
Dimensions (Diameter x H): 400 x 1120 mm
with lightning rod and mast: 400 x 3400 mm
Weight including antenna rods: 3.8kg

Lateral thrust due to wind with constant wind speed
150 km/h approx. 135 N
180 km/h approx. 195 N
(data with lightning rod and mast)

1 Depends on software configuration.
2 option (for VHF air band 118 ... 137 MHz)
3 For undistorted wave reception and sufficient field strength. Measurement is made with continuous vertically polarised signal, without modulation at a constant frequency by changing the angle of incidence in order to exclude site errors. Angle variation is done by rotating the DF antenna on a rotator.
4 System sensitivity for ±1° bearing fluctuations (cable attenuation of less than 2dB between antenna and the receiver).


Rt_1000_receiver Rt_1000_antenna