Ham Radio Stations
Club and Contest Station DF 0 UDThe HFT departement operates the club and contest station DFOUD on the roof of building BB (12th storey) at a height of 55m with activities in Shortwave (SW), VHF and Microwave Bands.
Generell View of Building BB
SHF-Beacon DB 0 GW in Duisburg
Call sign: DB 0 GW Location:
JO 31 JK
51° 25' 36'' Nord
6° 47' 24'' Ost
Height above S.L: 55m Modulation: A 1 A Send out:
Call sign, Location, Frequency
2 Minutes CW
Long time stabilised: 1 E-13 / h
Short time stabilised: 2 E-9 / h
Frequency: 2320.85 MHz 3400.85 MHz 1296.95 MHz 5760.85 MHz 10368.85 MHz 24048.85 MHz Output Power: 100 mW 50 mW 100 mW 100 mW 100 mW 50 mW Antenna: Double Helix antenna, horizontally polarised, omni-directional Waveguide Slot Antenna with 2 times 8 Slots, horizontally polarised, omni-directional Gain: approx. 7 dBD approx. 9 dBD
Double Helix Antenna for 2.3 GHz und 3.4 GHz
Repeater Radio Station DB 0 DRSince 1991 our department operates an amateur radio transmitter station for the 70 cm band, which was built by radio amateurs, members of the staff and students. The automatic transmitter station serves mobil and portable radio stations to communicate with each other intra-city. The transmitter signal is frequency modulated and radiates through a vertical polarized omnidirectional antenna at the top of our building BB.
Relais-Antenne auf dem Dach Specification of the Repeater Radio Station Output Power Level: P = 10 W Location: Building BB of Area Bismarckstrasse 81 (55 m over Ground) Range: approx. 30 km Output Frequency: 439,35 MHz Input Frequency: 431,75 MHz
Waveguide Slot Antenna with Horizontal Polarization and Omnidirectional PatternVertically installed omni-directional Antennas are developed for the operation of the beacon and the ATV-relais in the range of cm-wavelength on the basis of rectangular waveguides with arrays of slot radiators in one or both broad walls. A QBasic code was developed for the design and dimensioning of antennas. You can download the latest version HLSSA54.bas. It includes comments and references to publications on the basic design data in UKW-reports 1/91 (S. 50-55) und 2/91 (S. 71-77) as well as the IEEE Antennas Propagation Magazine december 1991 (Vol. 33, No. 6, pp. 45-47).
Photo of a 13-cm-Antenna with
Measured Omnidirectional Radiation Pattern
of a 23-cm-Antenna with 12 Pairs of Slots
Inverted-V Wire Yagi Array with Switched Beam Rotation for Frequency f=14MHz
Inverted-V wire switched beam array antenna on the roof platform.
For better visibility, the dipole wires have been colored.
The antenna utilizes six wires sloping under 30° elevation angle from the top of the roof platform tower in 7 meter height. Using a switch unit, two wires are selected for the active dipole and are connected to the feed cable; two wires are selected as parasitic elements and are connected to a capacitor as reactive load. The remaining two wires are left idle.
By cyclic interchange of the selected wires, we create six different combinations with radiation patterns separated by 60° in azimuth and covering 0 - 360° of pattern rotation.
Six wire arrangement of the switched beam array. Sketch of principal patterns created by six selections of wires.
The switch unit employs signal relays on a printed circuit board and the relays are remotely controlled by the operator using a digital circuit board with a 6-position rotary switch: Changing beam pointing direction is practically without inertia.
The antenna was realized by our student, Ashraf Abuelhaija, as part of his Master thesis in 2010.
His thesis is available on request as a PDF document from the department.
A paper with detailed information on the design and performance was published in QST, December 2011, pp 34-37!.
HamnetHAMNET is a special wireless LAN for radio amateurs. It uses frequencies on 2,3GHz and 5GHz bands.
User access (13cm) 2397MHz User access (6cm) 5695MHz Link to (in use) DF0MHR (Mülheim a.d.Ruhr)
DB0OHL (Gelsenkirchen Scholven)
Projected Link DB0WES (Wesel)
- For more information about hamnet visit this link(Information in german language)
Amateur Radio Links
- German Amateur Radio Club, Homepage
- Funkamateur, periodicals
- Hamradio, Classified advertisements, News, Downloads
- Software Downloads
- ARRL, Homepage of the American Amateur Radio association
- Funkbörse, Advertisements, Online-Auctions
Responsible / Contact
Please contact Prof. Klaus Solbach.