April’s Meeting

Annual Constructors’ Exhibition

Here are the rules.

  • Entries must have some relevance to amateur radio.
  • Entries must not have been shown at a previous CARA Exhibition.
  • Entries must have been constructed within the previous couple of years or so.
  • Entries must have been built or heavily modified by the exhibitor who must be a member of CARA.
  • Kits built by the exhibitor are permitted.

The following awards will be available for presentation:

  • The Bill Brown G5BK Cup for  “The Best in Show”.
  • The Pat Moore G3IKR Memorial Cup for “Innovative Construction”.
  • The Roger Kendall G0UPU Memorial Cup for “Best Software or Computer Related Project”

An exhibitor winning the same award for two consecutive years will not be eligible for that award the following year but, if rewarded by the judges, will receive a certificate instead.

Thursday 18th April.  7.30pm for 8pm in the Premier Suite, Cheltenham Town Football Club, Whaddon Road, GL52 5NA. Visitors and prospective members will be made welcome.

September’s Meeting

Aerials, Transmission Lines (Coax), Transmission Line Transformers and Transformers.

Thursday 21st September at the Premier Suite, Cheltenham Football Club.  7.30 for 8pm

The stimulus for this talk was my lack of understanding of how to determine the voltage at the end of an aerial, needed for the new regulations, and the operation of the 49:1 baluns so often used to feed wire aerials. The answer, it turns out, to these and other problems is to be found in determining and analysing the equivalent circuit of the aerial, transmission line, transmission line transformer and  transformer.

In the talk we will look at the early contributions to radio of Faraday, Maxwell and a little known maverick Heavyside, and see how a telegraphy operator sorted out a load by identifying the correct equivalent circuit for a transmission line. We will then look at the equivalent circuits of the afore mentioned RF components and see how wonderful computers are at doing sums to give us an insight in to the operation of these RF components. Don’t worry I will keep the maths to a minimum and give you a warning before showing any equation! While there will be a few equations in the talk, it is my intention to provide a clear practical view of how these devices work rather than produce a maths induced coma in the audience.

At the end of the talk I hope we will all be able to go away having a better understanding of how aerials, transmission lines and transformers work.

Mike G4GHL

CARA AGM December 2022

At the AGM on 15th December the Chair, Tony G3YYH, welcomed 24 members and one prospective member to the meeting – a good turn-out considering the freezing temperature and slippery road conditions.  A further 20 members had sent apologies for absence.  These numbers reveal a healthy interest in the activities and wellbeing of the club.

The reports from the Chair, the Treasurer and the Membership Secretary were all taken as read and approved without comment.

The Bernard King G3CEG Memorial Cup was awarded to Simon G6AHX for his noteworthy and praise worthy activities on the VHF and UHF bands.  The full citation will be published in January’s CARA News.

The Committee recommended that, in view of the healthy state of the club’s bank balances, the annual subscription should remain at £15.  A motion to this effect was proposed, seconded and duly carried without dissent. 

The following were elected as Officers:

Rich M0XRB – Chair.

Alan M0NRO – Secretary

Tony G3YYH – Treasurer

Andrew M0MVA – Membership Secretary.

The following Ordinary Committee Members were elected:

Larry G0SDG,   Mike G8NSZ,  Smurf M0URF

The Chair noted that Derek G3NKS would be co-opted at the first meeting of the new committee.

(The new committee takes over on 1st January 2023).

Simon G4SGI was elected Accounts Examiner.

The chair expressed the committee’s grateful thanks to Tony G3SNN for serving for many years as the Accounts Examiner and expressed their disappointment at his understandable decision to stand down this year.

Rich proposed a vote of thanks to Tony G3YYH, Derek G3NKS and James 2E0RLE for all the valuable work they had done while in post as Chair, Secretary and Treasurer respectively.  This proposal was approved and endorsed by warm applause.

The meeting was closed at 20.26.

A social evening followed with a plentiful and wholesome buffet provided by the bar staff.

Posted by Derek G3NKS

Fun Field Day

Over the weekend of 16th to 18th September CARA held another one of its popular Fun Field Days, this time from a field between Colesbourne and Wittington. A good number of members set up and operated their own portable stations and enjoyed the benefits of a very low noise rf environment, so quiet in fact that at times some of us wondered if our antennas were still connected! We also benefited from a spell of very good hf propagation conditions with some interesting DX being worked on QRP.

Early on the Saturday evening we were joined by a few family members and friends for one of Smurf M0URF’s excellent pizza BBQs. This was followed by much chat in a tent warmed by a lovely wood burning stove (with chimney exhausting through the tent roof) and by modest quantities of beer, cider and coffee!

Most of us packed up and departed early Sunday afternoon after a very enjoyable time spent playing radio and conversing with fellow club members. Very many thanks go to Rich M0XRB and Smurf M0URF and their helpers for all their hard work planning, setting up and clearing away the field day operation. There was talk of holding the next one in December!

September’s Meeting

On 15th September at a well attended meeting Tony G3YYH and Rich M0XRB told us about their trip to France in June to join the D-Day commemoration events there. They took with them (drove) an ex-WW2 CMP (Canadian Military Pattern) vehicle full of appropriate ex-military radios including an R107 receiver, a WS-12 transmitter, a WS-52 set, an R109 receiver and several other pieces of kit.. By prior arrangement they operated from a number of WW2 related sites, mainly on 80m AM. Tony and Rich’s talk, accompanied by many “slides”, was well presented and well received. Many thanks to them both for a very interesting evening.

June Meeting

On Thursday 16th June we’ll be “On-the-Air” at the Cheltenham Football Club. in Whaddon Road.  Members are invited to come along and operate /M or /P from the car-park.  If previous years are any guide, we’ll have members operating on bands from 1.8MHz up to UHF and may be even higher frequencies using voice, data and CW modes. With such a wide diversity of bands and modes on display, in past years these sessions have been good fun and instructive, and no doubt this year’s will be the same.  Let’s hope though for favourable weather!  Please come along and enjoy the evening whether you will be operating or not.  The bar will be open as usual, serving tea and coffee as well as beer.

Derek G3NKS Secretary

May Meeting

In a change to the previously advertised meeting, on Thursday 19th May members are now invited to bring along something or somethings from their shacks which will be of interest to other members.  May be something old, may be something new.  May be something built.  Maybe a useful software package. May be pictures of shacks or antennas, now or from the past.  Photos of past club activities would be good to see.

Please do bring along something and let’s have a successful meeting with plenty to see and chat about.

March Meeting Report

The annual Constructors’ Exhibition, held on Thursday 17th March, was well attended considering it was race week in Cheltenham and the consequential heavy traffic.

Ten exhibits were on display, ranging from the large to the small, from the complex to the simple. It was pleasing to see such a wide range of excellent exhibits showing that home construction is still alive and well among CARA members.

The Bill Brown G5BK Memorial Cup for “Best in Show” went to Keith G3XGW for his recently built 1930s 0-V-1 TRF(Tuned Radio Frequency) receiver using components from that era. 0-V-1 indicates that the receiver had no RF stage, a detector (V) and one AF stage. It was a fine piece of home construction which looked looked very authentic and so it well merited the Best in Show award.

The Pat Moore G3IKR Memorial Cup for “Innovative Construction” went to John G8CQX for his stereo code processor using a home constructed and built PCB. The processor feeds left and right signals to stereo earphones which gives the impression that the signal is moving from left to right, or from right to left, as the receiver is tuned across the signal. A very useful technique for separating closely spaced CW signals. An excellent adaption of a technique first developed many years ago.

The Roger Kendall G0UPU Memorial Cup for best software and computer related project went to Rich M0XRB for his remote controlled station set-up. Rich demonstrated how he could control and operate his remote station using an iPad and a DJ console. The station consisted of a Flex-6400 SDR transceiver with a Palstar auto-ATU and a 122m wire loop above a metal roof; the station being controlled by a Raspberry Pi. A very impressive set-up well worthy of the award.

Congrats to the three winners and many thanks to all the exhibitors for helping to put on such a good show,

CARA On The Air

In place of this month’s meeting, let’s get on the air and have a chat with fellow club members. Date: Thursday 19th March, from 20.00hrs onwards.

Try one or more of the following (in order of preference):

GB3CG Repeater on 145.725MHz or 145.400MHz FM.

  Or for those who don’t have access to 2m:

28.450MHz USB or 3.675MHZ (or thereabouts) LSB

Appoint a net controller who will ensure that everyone gets a turn. As there may well be newcomers, please introduce yourself by first name. Also these nets may be a good opportunity to offer help to members who are self-isolating or to ask to help.  

. Good luck and have fun. 73, Derek G3NKS