Our very own Vin G4JTR has written a rather excellent paper covering the advantages and the nuances of EFHW – end-fed half-wave – multi-band HF antennas.

It’s great to get some first hand experience and sensible analysis of this often over-simplified subject area.

Read the full article here:

We look forward to Vin’s next planned article – on noise, and presumably, its mitigation.

This year, RADARC celebrates its 90th birthday. Through the year, the members plan to run some events to celebrate this special year.

To kick us off, Michael M0MPM has organised and activated the special event callsign GB0RDG for an initial one month period. Michael will be in touch with members soon with an update as to how they can participate with this callsign.

Min G0JMS has been in contact with Ofcom and hopes to bring us some exciting news shortly – watch this space.

We anticipate that the summer time will be a great time in particular for special commemorative activations and other events relevant to the big anniversary.

All members are encouraged to share their thoughts and ideas around the club and with the committee – and just to get out and have fun – after all the club is nothing without its members.

This evening we gave a warm RADARC welcome to David G1EHF for a talk entitled “Portable Operating on Microwave and Millimeter Wave”. David gave a great talk about particularly the practical aspects of operating portable microwave, all the way up to 122GHz using RADAR chips from cars, and kindly brought along some kit for inspection. He is often to be found up Walbury Hill in the North Wessex Downs, picking his way among various evidence left by sheep in search of the perfect spot to place the mast.

David’s presentation was recorded and we hope to be able to bring it to members in due course.

We thank David for his talk and hope to have him back in future.

Thanks to Steve G8CSK, RADARC members recently had the opportunity to visit the National Grid ESO (Electricity System Operator) control centre near Wokingham.

We were treated to a warm welcome, a very informative presentation from two members of operational staff, and a period viewing the control room itself from the elevated viewing gallery at the rear, with great explanation given, throughout which our hosts enthusiastically answered the inevitable barrage of great questions from our members.

The visit comes at a period of change for National Grid ESO in their transition to becoming the National Energy System Operator, a new, independent, public corporation that will be responsible for planning Britain’s electricity and gas networks and operating the electricity system, and with “embedded generation” – solar and wind connected to downstream distribution networks over which the system operator have no control – increasing rapidly. We learned a great deal about the realities of the strategic and operational side of balancing the grid, both economically and technically, having a direct impact on grid frequency and ultimately safety and security. It is fantastic to see first hand how carefully and professionally this is national-scale system is managed.

Our sincere thanks go out to everyone involved in organising and hosting us, and especially to our two hosts on the day, Pat and Ceiran.

On 29 February 8pm UTC, Vin G4JTR hosted a club top band net, on 1850kHz.

Using a George Smart Wellgood active receive loop approx 1.5m diameter inside a roof space, reports at M0LTE HQ were:

Vin G4JTR 5/9+ -59dBm
Michael M0MPM 5/9 -68dBm
Brett 2E0HFW 5/8 -75dBm
Nick M0NPK 5/7 -82dBm
John G4RDC 1/6 -92dBm
Alan G3UQW 5/9 -73dBm
Simon M0ZSU 1/6 -92dBm
Jeff G4AAO 1/6 -93dBm
Ian G8NXJ 5/8 -78dBm
Loz G2DD no trace
Min G0JMS 5/6 -88dBm
Dave G4RGK 3/7 -90dBm
Robin G4IWS 5/9 -59dBm
And a late entry Steve 2E0SBH 4/6 -90dBm

This was against a noise floor here of -93dBm in 3.3kHz. Virtually no QSB.

Several participants were audible on the Hack Green web SDR. The noise floor was fairly high for some, but with few exceptions generally reports were good to very good. Some tips were exchanged on audio setups, resulting in significant improvements even during the net. There was a Zoom backchannel being used to exchange signal reports and for a post-net chat.

No doubt this fun event will remain a popular fixture in RADARC calendar.

Announcing the grand opening of the RADARC official tat shop!

We have today launched an online store with a wide selection of goods proudly showing off the RADARC logo.

Caps, polo and tee shirts, hoodies, coasters, mugs, water bottles, phone cases, stickers and more – we’ve got it all. Items are made on demand by the shop supplier and not handled by the club.

The store is set up as a non-profit store, that is, the club does not take a margin on sales, and nor is there any cost to the club. This is just about getting the word out there and looking your finest!

Visit the online store and make your purchases today at https://radarc.myspreadshop.co.uk

We were recently delighted to welcome Charles Coultas for his club presentation on “The discovery of encrypted radio signals, both Enigma and Lorenz leading to the development of Colossus” for a lecture covering:
– Why Bletchley Park was chosen, and who worked there
– Government concerns about what is going on in wartime
– Alan Turing who joined at the outbreak of WW2
– Enigma, how it works and how it was broken by Turing
– The purpose and importance of radio communications
– The mathematicians at Bletchley Park
– A light hearted dip into some aspects of cryptography
– The strange radio signals from 1941, what they were and how the code was broken, and how this shortened the war
– How the “computer” came about and Turing’s part in it

We’re pleased to say you can re-watch Charles’ whole presentation right here:

With thanks as always to our video editor Chloe 2E0JPM.

Further to the January 2022 RadCom article entitled “A Collaboration of Enthusiasts”, we recently welcomed club member Paul Hearn who gave us an introduction to Radio Astronomy and the UK Radio Astronomy Association.

Paul kindly gave his presentation in person at our new venue, the Scout hut. There’s something for all wavelengths here from VLF to microwaves!

You can re-watch the full presentation right here. Don’t forget to check out all of our other videos on our YouTube channel.

Following on from his November 2021 RADCOM article “Amateur radio and the arrival of the transistor” we recently welcomed Duncan James, M0OTG as our guest presenter.

Duncan gave an excellent talk showing the historical development of the transistor through the ages from primitive laboratory pieces through to today’s hyper-miniaturised devices.

You can watch Duncan’s talk again right here:

If you are interested in joining RADARC for our meetings either in-person or online, please check out the Membership page of our website.