Contesting

Tobias (DH1TW)

3 minute read

Once your contest station grows bigger and you add more antennas to turn, it becomes quite annoying to move around the physical rotator controllers between the operating positions inside the shack. Desperate for a better solution, I developed a server software which provides access to the Rotators through the network. Now all rotators can be controlled either directly through Win-Test, TCP socket, or through a Web-Interface.

Tobias (DH1TW)

2 minute read

dxheat landing page

Over last 8 month I was digging deep into Web Development. The result went yesterday public – DXHeat.com. Instead of building just “another” Web DX Cluster, I tried to build something innovative with new, unique features. Best is to check it out by yourself!

Tobias (DH1TW)

1 minute read

Last weekend I was invited to speak in the Contest Forum at HamRadio convention in Friedrichshafen, Germany. The presentation was about our Contest Activity from northern tip of Qatar. We participated in the Multi/Multi category and used almost exclusively verticals antennas. For everyone who missed the event, here are the slides! A73A CQWW 2012 Contest operation from the Desert of Qatar from Tobias Wellnitz

Tobias (DH1TW)

2 minute read

In preparation of the upcoming CQWW 160m Contests my friend Hannes, DK1NO was so kind to give me one of his W7IUV broadband, high IP3 preamplifier. Thanks, Hannes! Without knowing the exact performance data, I ran a few measurements with my Network Analyzer on the amplifier to determine the Gain and it’s operational fitness. Read on for measurement results and additional notes on how to measure active components.

In the pictures below, the measurement setup can be seen. I’m using a high precision USB Network Analyzer made by DG8SAQ (90dB dynamic range), a Mini-Circuits BNC Calibration kit and some Mini-circuits attenuators.

Tobias (DH1TW)

3 minute read

2el vertical array for 160m

In CQWW 160m we are planning again a serious participation. This time we want to errect a 2el vertical Array for 160m towards the US. In this post you will find some detailes regarding our unique situation and some design thoughts.

Tobias (DH1TW)

2 minute read

 During my stay in Ecuador I was able to operate two days under my US Callsign as HC2/AL1O. Special thanks to my host Alberto, HC2AQ who offered me his shack. Within two days, 1700 QSOs found their way into the log.

 Read on for pictures, online log & QSL information.

Tobias (DH1TW)

8 minute read

damaged tube alpha91b

It finally happend…. After a decade of reliable service, my Alpha91b amplifier broke. Most likely on it’s way to Spain one of the tubes broke. During the comissioning at ED1R contest station, fire & smoke shot out of a chimney. The first shock was big, but a few measurements confirmed that just the tubes were broken. In this blog post I will share the knowledge I gained during during debugging, comissioning and breathing new life into the amplifier.

Tobias (DH1TW)

6 minute read

A73A Contest Station

This year I had to honor to be invited by the Qatar Amateur Radio Society (QARS) to operate the CQ WW SSB contest with them. The station set up in a fieldday style on the northern tip of Qatar, about 100km way from the capital Doha. We are directly located at the beach and used almost exclusively vertical antennas. A73A entered in the category Multi Operator / Multi Transmittors, running 6 Stations in parallel. Keep on reading for some pictures and lessons learned.

Tobias (DH1TW)

1 minute read

VP8ORK LogoA few days ago I had the honor to be invited for dinner with the VP8ORK Microlite DX-Pedition Team. Before leaving from Ushuaia, southern Argentina towards the Islands of South Orkney the team assembled itself in Buenos Aires. Thanks to the LUCG (LU Contest Group) and especially the help of Claudio, LU7DW we had a fantastic barbecue in one of the famous “parrillas” of Buenos Aires. While writing this, the VP8ORK is already QRV. If you haven’t worked them yet, go and give them a call. Here are a few pictures of this evening:

Tobias (DH1TW)

1 minute read

Last weekend I was invited to speak at the Contest Universtity in Friedrichshafen, Germany. This year I tried to visualize a rather abstract topic, the influence of technologies on the art of contesting. Mainly two topics are discussed: Information Management and Software Defined Radios. How new technologies affect the art of contesting Do you like this presentation? Please leave a comment and share your opinion with us!