In Part 1 - HERE and Part 2 - HERE we looked at:
Why would one setup a WSPR Beacon in the Southern Cape?
Particulars of the ZS1I Ultimate 3S Beacon.
Construction of the Southern Cape Beacon.
First station to spot the ZS1I WSPR Beacon on 40 Meters.
Reception of the ZS5SAM WSPR Beacon on an SDR and Antenna inside the Shack and other spotting stations that received the ZS1I WSPR Beacon on 40 Meters.
In Part 3 I will be looking at two Antarctic Research (WSPR) Stations that spotted the ZS1I 40 M WSPR Beacon recently. One fixed station and one a maritime mobile station.
Station 1: DP0GVN
AntarcticaNeumayer Station III
Ekstroem Ice Shelf
Atka Bay, Dronning Maud Land
Antarctica
Station 2: DP0POL
Antarctica
Research Vessel "Polarstern"
Home Port: Bremerhaven
Germany
Both the above stations spotted the ZS1I WSPR Beacon on 40 Meters on the 14 December 2025. See image below.
DPØGVN is a club station located at the German Antarctic Research Station "Neumayer III" in Dronning Maud Land, Antarctica. Find more on this outpost of global research at https://www.awi.de/en/expedition/stations/neumayer-station-iii.html.
WSPR Beacon
- Station Info
The setup consists of a receiver and a transmitter which independently of each other operate in the WSPR segments of the amateur radio HF bands.
- Receiver
The receiver is located at the "SpuSo" which is the station's air chemistry laboratory. SpuSo's main purpose is to collect continuous, year-round and long-term data records for important gaseous and particulate trace components of the troposphere. This observatory is located about 1.5 km south of the main station where it finds an outstandingly clean air environment.
This is a perfect place for a receiver setup because the RF environment, too, is amazingly QRM-free with a noise floor well 20, 30 or even more dB below of what we are used to in urban areas.
The receiver is a SDR built around three Red Pitaya (StemLAB 125-14 with 50 dB preamplifier). They permanently observe all eleven WSPR band segments between 160m and 6m and upload the spots to wsprnet.org. A BananaPi and a RaspberryPi single board computer take care of control tasks.
The antenna setup consists of two two triangle-shaped horizontal loop antennas with 1:4 baluns. The lower bands are received by an antenna with a circumference of 171 meters, the upper bands use a shorter loop of 61 meters.
The antennas are mounted on short masts about one to two meters above the ice shelf. This is not "above ground" as the ice shelf is almost invisible to HF. You even can use antennas lying flat on the ice to do HF QSOs! The real ground is about 200 meters below as this is the average thickness of the ice shelf in this area. Every year precipitation adds about one meter of snow and ice. Therefore the antennas have to be reestablished regularly to not risk having them covered by snow.
- Transmitter
The transmitter is located at the main station and is based on the TX design of the Charly-25 SDR project. Ats it heart is another Red Pitaya StemLAB 125-14 which feeds a rock-solid PA designed to emit up to 20 watts RF. The Red Pitaya runs Pavel Demin’s WSPR transceiver software. A PC Engines APU2 single board computer is in charge of control and monitoring tasks. RF output, SWR and system temperature are constantly monitored.
The antenna is an approx. 20 meter long wire installed on the southern part of the station’s roof. The wire runs in North-South direction and is matched by a 1:9 Unun-type RF transformer. While not being a high-performance antenna it is well suited for the task because it is broad band and believed to be able to stand the stress caused by the extreme Antarctic whether conditions.
The transmitter transmits on all WSPR segments between 160m and 6m on a round-robin schedule. One complete cycle takes 30 minutes. The bands between 40 and 17 meters are served twice per cycle because these offer the best chances for the signal to be heard. So these four bands are visited four times per hour, the other bands twice per hour. The RF output is 5 watts on all bands.
Update June 2020: On 2020-06-04 something in the RF transformer feeding the long wite antenna broke causing the antenna to be unusable. Therefore we are currently transmitting with the 5.5m vertical antenna which was already in use for the project before 2020. This antenna offers a less favorable radiation pattern when compared to the long wire, so expect somewhat degraded reception opportunities. Maintenance work at the antenna can only take place during Anarctic summer so that the repair will not be executed before January 2021.
- The Project
This setup is a long-term project realized by the Technical University of Munich (TUM) and the Hochschule Bremen City University of Applied Sciences (HSB) in cooperation with the Alfred Wegener Institute Helmholtz-Zentrum für Polar- und Meeresforschung (AWI) and the German Amateur Radio Club (DARC). AWI operates the Neumayer Station III and provides logistics. DARC builds and maintains the receiver and transmitter setup.
The project is meant to run several years to gain long-term data on radio propagation and spectrum pollution in a very specific HF environment as the station is located within the southern auroral oval. The setup will see changes in the future -- we will keep you updated here. As the station is inaccessible from the outside world for about eight months during south polar winter modifications will usually happen during the Antarctic summer season between November and February.
DP0POL is only operated from the vessel when it is en route in international waters, so the call sign always is DP0POL/mm. You can follow the ship's research activities in our Polarstern Web App. For the ship's current position, please check the SEAICE portal.
I made two adjustment on the ZS1I Beacon and it is now running flawlessly. Before I had to "reboot" the beacon every second day. Since the setup adjustments I just left the beacon and it operated continually.
In Part 4 we will be looking at changing the band and frequency as what the beacon was intended for. More on this in Part 4.
Images: (Click on the images for larger view.)
