Dorking & District Radio Society

Recent Meetings and Events

Christmas Dinner

13 December

We enjoyed an excellent meal for members and partners at the Stepping Stones public house (Westhumble). Afterwards, we were entertained by an original radio-inspired song by John Kelly.

Annual General Meeting and film

26 November

Our annual review of the club's activities and finance over the last year, and the election of new members and roles on the committee. This was followed by a film about using 3D printing techologies for amateur radio applications.

Hermes Lite SDR with Spark SDR software

22 October

Alan Hopper demonstrated several generations of software defined radios, from the experimental "High Performance SDR" to the latest version of the Hermes Lite SDR, which follows similar principles but using a mass produced broadband modem chip which includes a QRP transmitting facility. Alan also showed us his Spark SDR software application, which provides a conventional user interface to the above hardware. It is capable of decoding multiple FT8 messages simultaneously, and we saw it in action with an antenna.

The Earth Beneath and the Sky Above

24 September

Colin Berry explained the various ways in which energy near an antenna can be absorbed by nearby objects, such as the earth beneath it as well as other building features. He went on to show what effect the proximity of a real ground would have on the radiation pattern of various antennas, and described a method of using modelling software to assess the overall efficiency. He gave some reasons why near-vertical incidence skywave propagation is used in practice, and explained how the ionosphere behaves for nearly vertical radiation at various frequencies and times of day.

Heritage Station

7 September

Our now traditional special event station GB0NT was set up on the "helipad" near the front of the house at Polesden Lacey. A good number of visitors took an interest, perhaps attracted by the inverted-V, VHF and loop antennas, and maybe intrigued by the operators, displays and vintage radios. The nature of amateur radio was illustrated by the fact that although signals could be heard clearly from all over Europe and beyond, we could hardly get a mobile data signal from the nearest mast.

Summer Social

27 August

This most enjoyable evening was at Tom and Sue Ellinor's home in Banstead. Around 20 members and partners attended, enjoying fish and chips and a choice of desserts. Please see the updated Socials page for an updated photo.

South Downs Expedition

23 July

A very successful and well attended evening meeting at the Devil's Dyke, to operate portable equipment together and enjoy dinner afterwards. Please see the updated Devil's Dyke location page for a new article with photos.

CW Still Here

25 June

An entertaining evening exploring the world of Morse (or should it be Vail?) code. John Kelly introduced the topic with a historical account of how and why it came to be created and used, and then explained about all the different types of keys which can be used to send it. Two teams were then formed and John ran a fun competition for us to practise sending and receiving messages in various ways, including blinking! The evening rounded off with a display of vintage and modern keys, some CW operating and a demonstration of CW practice software.

Protecting earth from the ravages of the sun

28 May

A very informative evening learning about activity at the sun's surface and the consequences in the vicinity of the earth, including aurora, radio blackouts and threats to satellites and national electricity grids. Dr Colin Forsyth from the Mullard Space Science Laboratory explained the interaction between this high temperature plasma and the earth's magnetic field, including concepts like "Bow Shock" and the Magnetosphere.

ICQ Amateur/Ham Radio Podcast

23 April

We learned about this fortnightly audio (and sometimes video) magazine on topics of interest to radio amateurs. Martin Butler explained how the programmes were planned, recorded by a team of presenters, edited then made available to download from the internet via various websites. We also watched some actual recordings featuring good quality outside-broadcast reporting from rallies and events. An excellent way to keep up to date with relevant news and comment, including unbiased real operating experience of equipment.


26 March

Mike Potter gave a detailed demonstration of various logging programs. Starting with Logger32, he demonstrated how logging programs can do a lot more than just passively record contacts as in a traditional log book. Logger32 is not only free and runs on quite basic computers, but can connect to and control a variety of amateur radio equipment such as selecting and tuning multiple transceivers and operating an antenna rotator. It also connects to DX cluster and ClubLog to provide additional information about potential contacts. Mike explained the key role that the ADIF data format plays in transferring data between logging systems, including ClubLog.

Mike also demonstrated some other logging programs - HamRadioDeluxe, Swisslog, Turbolog and Log4OM.

J-Pole and Slim Jim Construction

26 February

Tom Ellinor showed the club how these antenna designs work and how to calculate the various measurements. We then formed 4 teams and set about making one of them for ourselves out of ladder line. The intention was to create a highly portable antenna for 2m which could be hung up and fed at the bottom.

The basic construction was simple enough, but when the finished products were tested using an antenna analyser, the resonant frequencies were not quite as predicted. The beauty of the constructional approach then became evident: it would be fairly simple to adjust the lengths to get a good match at 145MHz.