CUWS is 100 Years Old

CUWS was formed on October 13th 1920 so we are now 100 years old. We had planned a birthday dinner at Caius (our place of birth) in a couple of weeks time but Covid-19 put paid to that. Tentatively we hope to have a 101st birthday dinner on Saturday November 6th 2021. Please let Martin G3ZAY know if you are interested in attending –

Trevor Gill G8IBO found an interesting academic article about the early days of CUWS written by Jeff Hughes from Manchester University.  You can read it online at

Trevor has also prepared a shorter history of CUWS based on Jeff’s and other material. 100 years of CUWS

Martin G3ZAY  22/10/2020

CQWW SSB Contest October 2019

The CUWS Team achieved first place for England (and the UK) in the multi-op single transmitter category. Normal antennas at the shack were supplemented with a 40m 4-square, 80m vertical, and 15m monobander on a SCAM 12 tower (Tnx M0LCM).

ZC4UW Cyprus Sovereign Base Area Operation

Six members of the Society and one guest were active from the western Sovereign Base Area on Cyprus from 2-8 January 2020. A record (for CUWS) 26,000 QSOs were made from 160-15 metres (including a handful on 12/10/6). Modes used were CW, SSB, and RTTY. The team used 4 Elecraft K3/KPA500 stations and one KX3/Juma combination. The antennas were: 160m inverted L, 80m quarter wave, 40m quarter wave, 30m ground plane, 20m ground plane, 17m vertical dipole, 15m vertical dipole. For 60m either the 160 or 80 metre antenna was used. The QTH was a beach cafe that had closed for the winter. The team picture is below. Ops from left to right were: Michael G7VJR, Rob M0VFC, Simon G7SOZ, Martin G3ZAY, Stavros 5B4AFM / M0BBB, Dan M0WUT and Dom M0BLF.

The ZC4UW Team

December 1st & 6th – Youngsters on the Air Activation

CUWS hosted two 8 hour slots in the December activation of GB19YOTA for Youngsters on the Air. 1000 QSOs were made, mainly on 40 and 20 metres CW and SSB.

Dan M0WUT kicked things off on 20m CW:

He was joined shortly afterwards by Charlie M0ZCJ on 40 SSB:

Next up was Nikolas M0IPY on 20m SSB:

And William M0WJE on 40m SSB (20m CW later):

William introduced Jared KC1LZJ to the sound of the bands from this side of the pond:

And Aly M0WSE finished off on 20m SSB:


28 Nov 1900: Eloy de Lera Acedo: “Unveiling the Early Cosmos”

Cambridge University Engineering Dept, LR6, 1900 on 28/11/19

Dr Eloy de Lera Acedo, of the Cavendish Laboratory, will address the Society on his research.

Image credit SKA Organisation/Swinburne Astronomy Productions

One of the missing pieces in the puzzle of the history of the Universe is the transition from the Dark Ages after the Big Bang, when the Universe was an empty vast volume, to the complex realm of galaxies, starts, etc. that we can observe from Earth today. In this lecture, Dr de Lera Acedo will give an overview of the current efforts (some of them led from Cambridge) to observe and study the very early lights of our cosmos. Low-frequency radio telescopes, aiming at observing the signature signal from Hydrogen in the early Universe, are widely considered the prime tool to unveil the remaining mysteries around the formation and early evolution of the first luminous objects in the sky. Dr de Lera Acedo will talk about the science case named 21-cm radio cosmology and the different current (eg. REACH, HERA) and future (eg. SKA) experiments and observatories dedicated to this mission.



CQWW SSB Contest 2019

CUWS entered the major CQWW SSB contest last weekend (26/27 October) in the Multi-operator, Single Transmitter, category. In practice this means two transmitting positions – but one is designated as only being able to contact countries or “zones” that have not yet been contacted on a particular band. The usual 3 element SteppIR Yagi was supplemented with a 5 element 15m Yagi on a 12m SCAM mast, a 4-square phased array for 40m, and a single quarter wave vertical for 80m. The last two antenna systems will be in place for members to use until the end of March (if the vertical parts survive the winter gales).

Conditions were as poor as one would expect at the bottom of the sunspot cycle but we managed 2802 contacts over the 48 hours and are hoping for 1st place in our category again.

Operators included a number of students and recent alumni.



G6UW Member on Gough Island in 1955

In 1955, Martin Holdgate (now Sir Martin) then a recent Cambridge graduate organised a scientific expedition to Gough Island in the middle of the South Atlantic. He asked CUWS if a member would be interested in joining as the radio operator and electronics technician. Philip Mullock, G3HPM, stepped up and by late that year was active as ZD9AD from Gough Island. Thanks to Paul Johnson, ZS1S, one of Philip’s QSL cards has been scanned and sent to us as a memento of the expedition. Holdgate’s book “Mountains of the Sea” has more detail about the trip and includes a recollection that Philip kept a regular radio sked trying to contact an old school friend in the UK – entirely without success throughout the expedition.

Holdgate also commented on the nature of the typical amateur radio contacts as per the book image below:

QSL card sent to ZS1AB in Cape Town:

Philip retired to the Cambridge area and visited the current G6UW shack about 7 years ago (pictured) but sadly passed away recently.



22 Oct 1900: Jossy Sayir: “Information Storage on DNA”

22 October 1900, LR5, Cambridge University Engineering Dept.

Dr Jossy Sayir, a lecturer and researcher at Robinson College, Cambridge, will address the society on his research. It promises to be a most entertaining and engaging lecture.Graphic with DNA helix and binary data

There is a lot of digital information in the world — about three zettabytes’ worth (that’s 3000 billion billion bytes) — and the constant influx of new digital content poses a real challenge for archivists. Hard disks are expensive and require a constant supply of electricity, while even the best ‘no-power’ archiving materials such as magnetic tape degrade within a decade. One solution is to use DNA: a compact, robust molecule, as a storage medium. We call this DNA storage. The talk will introduce the technology for writing and reading DNA, cover data preparation and retrieval. It will also include an activity where participants will get to encode and decode their own messages into DNA in the form of coloured Lego pieces.




CUWS Talk – Feb 14th 1900 – GNU Radio: A toolkit for the Wireless World

The talk will be from 1900 in the Bateman Auditorium at Caius College on Thursday Feb 14th. All are welcome.

Derek Kozel is an officer in the GNU Radio project, president of the Cardiff University Amateur Radio society, and a PhD researcher at the Centre for High Frequency Engineering. He operates as MW0LNA primarily on the microwave bands and has a strong interest in Free and Open Source Software and enabling the use and understanding of wireless digital communications by students and in Amateur Radio.

The way we send information, whether voice, text, images, or video, has been evolving since Samuel Morse’s telegraph in 1836. As these systems become more advanced the standard electronics tools and knowledge which have been the Amateur Radio operator’s standard toolkit must be accompanied by software components. Together the analog, digital, and software are used to enable the modern communications modes such as Digital Video Broadcast (DVB), JT65 for moonbounce, FreeDV which has brought digital voice to the HF bands, and the wide variety of other new and exciting protocols.
GNU Radio ( is a free, graphical, software development toolkit that provides signal processing blocks to implement software-defined radios and signal-processing systems. It can be used with external RF hardware to create software-defined radios, or without hardware in a simulation environment. This talk introduces the software, demonstrates assembling complete transmit and receive systems, and shows a few examples of advanced applications.