Wednesday, 14 December 2016

CTARC Seasons Geetings! - Dec '16

To all our Cape Town Amateur Radio Centre members, friends and families, compliments of the festive season!

Stay safe on the roads...

The oscilloscope image was produced by Redcat on the EEV Blogspot

(URL: http://www.eevblog.com/forum/beginners/hello-to-the-eevblog-forum-and-a-little-christmas-season-oscilloscope-image/msg346205/#msg346205).

It is part of a growing new art form - Oscilloscope Art. If you want to see what can be done with an audio source and an oscilloscope, take a peek at the following YouTube videos:

https://www.youtube.com/watch?v=ytnt9l_WKxk

https://www.youtube.com/watch?v=ZaTuFB5QXHo

https://www.youtube.com/watch?v=YqSvkNjWnnQ

Friday, 9 December 2016

CTARC Ragchew December 2016

The December 2016 edition of the Cape Town Amateur Radio Centre's bi-monthly newsletter "Ragchew" has been published. Grateful thanks to Anne for this bumper Xmas edition!

You can download the December Newsletter as a PDF directly [here].

Alternatively it can be found on our Newsletters page

Tuesday, 6 December 2016

CTARC Calendar for 2017

CTARC members and friends can still purchase the CTARC Annual 2017 Calendar for a very reasonable sum, while stocks last. Proceeds of the sales go to CTARC club funds.

Printed in full-colour and laminated, the A3 size calendar features months and dates of the year, with CTARC meetings, events and national public holidays indicated.

The calendar will be on sale at our next club meeting in January 2017.



Thursday, 1 December 2016

CTARC December Meeting - 24 Dec '16

If we were going to have a December meeting for the Cape Town Amateur Radio Centre, it would be on the fourth Saturday of the month, which would make it Christmas Eve - 24th December.

But we are not. Our last meeting was the End-of-Year function braai on Saturday 26 November 2016, and our next meeting will be on Saturday 28 January.

So all that remains is to wish all our members a very Happy Christmas for 2016 and all good things for the new year of 2017!

Sunday, 27 November 2016

CTARC Photos of November Meeting - 27 Nov '16

Here are photos of the 26 November CTARC End of Year meeting:

We had a good turnout at the event. The weather was great and the company better!
Paul /ZS1S set up this magnificent MW rx with a frame aerial.
Solar powered, too! Provided music all afternoon
Tony / ZS1TM set up the braai fires...
Various items were on display for swop or purchase...

...Like this fine legacy VHF rig
Dennis / ZS1AU signs the LWHST certificates quietly, away from the crowds

Hylton / ZS1HPC (left) welcomes some newcomers
The ladies very kindly distributed the hamburgers & liquid refreshments

Rob / ZS1SA displays the 2017 calendar available for purchase



Ettienne / ZS1AX receives the Len Wells trophy (awarded to him
and his XYL Yolanda / ZS1CX) from Dennis / ZS1AU
Ettienne & Dennis in the clubhouse

New friends are made...
...And the proverbial rag is chewed
Testing ZS1S's discone antenna with Peter's RigExpert antenna analyzer
Karl / ZS1KC brought some bits & pieces to the Swop Shop too
The discone's characteristic wide frequency range was discovered
An acrobatic aircraft fly-past enlivened the late afternoon...
These guys had the staying power to make it through to the end!

CTARC Report Back on November Meeting - 26 Nov '16

The Cape Town Amateur Radio Centre held its final meeting for the year on Saturday 26 November 2016. Committee members arrived at the club house and started setting up the braai fires, tables, chairs and canopies from 11h30, in time for the main crowd to start arriving from 12h00 onwards. The weather was good and the wind not too strong. We were very pleasantly surprised to see how well attended the function was - around 50 people at one stage.

Our chairman Rob / ZS1SA opened the meeting at 13h00 and welcomed the club's members, guests and families. He then introduced Dennis / ZS1AU, who had donned his famous tuxedo for the official announcement of the Len Wells Ham Spirit Award trophy.

Dennis took some care to communicate that the award is not limited to CTARC members alone. A degree of subterfuge had to be employed to enviegle the prospective recipient into attending the meeting without giving the game away!

Congratulations go to Ettienne / ZS1AX, who, with his wife Yolanda / ZS1CX, are this year's recipients of the Len Wells Ham Spirit Award. Dennis told us that there had been seven nominations (and he broke with tradition by naming them), but Ettienne was top of the list for his steadfast sticking to his beliefs throughout a dispute with officialdom, where he even had to appear before a disciplinary committee. In the end, having won his point, Ettienne offered magnanimously to serve on the SARL Committee, which he now does. Ettienne accepted the trophy plus the certificates for himself and Yolanda from Dennis.

Ettienne gave a short speech on receiving the award, and thanked our club for the steadfast support he received throughout his stressful ordeal earlier on in the year.

The official business done, we all settled down to an afternoon of great camaraderie, natter, chewing the rag and meeting up with our friends. We were sustained throughout this by delicious hamburgers, ably cooked by Tony / ZS1TM and served up by Anne, Elsabe and Sandi, who were kept busy for a large portion of the afternoon feeding and watering hungry and thirsty hams.

We were very pleased to see a number of new faces at our meeting - some are radio amateurs who have just qualified, others are interested people from around Cape Town. Three new members signed up at the meeting! Welcome!

Members who had placed their orders earlier were able to collect their fancy gold CTARC Name Badges, which look very classy indeed. So classy in fact, that we suspect another batch of badges will be produced before long.

CTARC A3-sized Year Calendars for 2017, laminated and in glorious technicolor, were also on sale. A few were left over and will be on sale again at our January meeting. These useful calendars list all CTARC Monthly Meetings, Events and Committee Meeting dates as well as the public holidays for the year. They also make interesting table mats!

Paul / ZS1S brought along a beautifully constructed MW receiver - solar powered and with a large square loop antenna. This unique rig kept us freely entertained with music throughout the afternoon.

Peter / ZS1PGC brought along his RigExpert antenna analyser and he and Paul were busy checking Paul's discone antenna later on.

The Bring-&-Buy Swop Shop was also in operation. Tony / ZS1TK, Ian / ZS1SX, and Karl / ZS1KC all brought various items along to swop or sell. Excited clusters of radio hams were to be seen crowding around certain car boots which were opened to reveal their treasures within. These Swop Shops will be a continuous feature of our monthly meetings henceforth, with the Mega-Flea Market on 5 March next year being a major event.

Very grateful thanks must go out to a number of people without who's sterling efforts the meeting would have not been so enjoyable:

Rob and Anne, for organising the food and liquid refreshments, and especially to Anne, Elsabe and Sandi, for serving up the food all afternoon long;

Tony / ZS1TM, for patiently and expertly braai-ing the hamburgers;

Noel / ZS1FW, providing the bags of ice that kept the beers and cool drinks cool throughout the afternoon;

Dennis / ZS1AU, for making it all the way here to deliver the Len Wells award (and for wearing that tux in the blazing heat!). Also Tony / ZS1TK, for providing kindly transport for Dennis to and from the meeting;

All others who assisted with setting up, running the event and cleaning up / packing away afterwards.

The meeting ended at around 16h00. A most satisfying event indeed.

We look forward to seeing you all at our next meeting, which will be at the Clubhouse at 14h00 on Saturday 28 January 2017. More info on this meeting will be published in due course.

Photos of the November meeting are [here].

Sunday, 6 November 2016

CTARC Forthcoming End-of-Year Function - 26 Nov '16

Please make a note in your diaries now for Saturday 26 November 2016, which will be the Cape Town Amateur Radio Centre's annual End-of-Year function.

This is always a great social event and provides a chance to meet up with friends and fellow radio hams, some of whom have not been seen for some time.

Please note that the event begins at 12h00 (not the usual 14h00). The braai fires will be lit by 13h00. Committee members and those assisting with the event please be at the clubhouse by 11h30 sharp. The event will last well into the afternoon, as before.

Hamburgers, beers and cool drinks will be on sale. The CTARC will provide the braai fires, as well as ice for the cool drinks. Please bring your own meat and other braai-ables for the braai, as well as your own drinks if you would prefer something other than beer or cooldrink.

Further details will be announced here and on the CTARC Sunday morning bulletins in due course.

Saturday, 5 November 2016

CTARC Committee Meeting - 21 Nov '16

There will be a meeting for members of the CTARC committee, at 19h00 on Monday, 21 November 2016, at the CTARC Clubhouse.

Please note that this will be the final CTARC committee meeting for 2016 as we have no scheduled meetings in December of this year.

Please diarise accordingly.

Tuesday, 1 November 2016

CTARC Ragchew November 2016

The November 2016 edition of the Cape Town Amateur Radio Centre's bi-monthly newsletter "Ragchew" has been published. Grateful thanks to Anne for this bumper edition!

You can download the November Newsletter as a PDF directly [here].

Alternatively it can be found on our Newsletters page

Saturday, 22 October 2016

CTARC Report-Back on Bring & Buy Swops - 22 Oct '16

We were very pleasantly surprised to see the great responses to our proposed Bring and Buy Swops facility, which promises to be an attractive function of our monthly meetings from now on.

A number of club members brought along various bits and pieces to our October monthly meeting at the clubhouse, ranging from components and chassis to entire rigs. These items sat smugly in the clubhouse for the duration of the meeting, at the conclusion of which certain items were happily claimed and paid for by those who had been eyeing them throughout John /ZS1PB's very interesting talk.

I saw Tony / ZS1TK walking away with a fine Icom R71 receiver, Jaques / ZS1JPB toting some fine Phillips antique gear. Charles / ZS1CJO was hugely pleased to acquire a very nice little bug key. Even Nick / ZS1ZD managed to find space in his shack for a couple of solid metallic speaker boxes.

But wait! There's more! Not every ham was able to sell everything immeadiately, and we are confident that these items may return on occasion to subsequent meetings. Furthermore, we know of at least two members who were planning to bring some stuff but couldn't make it to the meeting.

A request, please, for bringers of goods to PLEASE PUT THEIR NAMES ON THE EQUIPMENT so the prospective buyers know whom to ask and to pay the money to! Some wannabe buyers had to wander around the meeting holding items above their heads, asking to whom the goods belonged. Also, if it doesn't sell, PLEASE TAKE IT HOME AGAIN!

All in all, a very satisfying afternoon.

Hands-on investigations of rigs, handies, mikes and headphones

Seriously vintage baekelite speakers and gear

The smle says it all - Charles has caught the CW bug!

This exquisitely retro piece of gear is as yet unclaimed...

In the background, ZS1TK tests his R71 on the club's antenna. It performed!!

Finally, to those who encounter Acquisition QRM from their significant
others when they carry heavy boxes into their QTH, we offer this
inspirational quote...

Report-Back on October Meeting - 22 Oct '16

The Cape Town Amateur Radio Centre held it’s October 2016 Meeting on the 22nd, starting at 14h00. The meeting, which was very well attended, was opened by Paul / ZS1S, who welcomed us all. He took the trouble to welcome back a number of old friends who had not been at the club for some time, as well as a number of newcomers, some of whom have just written their RAE and yet others who are involved with technical subjects at UCT. We do hope the newcomers will be joining our club, which now has a paid-up membership (and excluding life members) of over seventy strong.

We remembered Richard / ZS1RIC who is currently attending his wife in hospital, and we welcomed back Hugo / ZS1HSF, who has returned from a spell in the white house.

Noel / ZS1FW then gave a report-back on the recent JOTA field station set up in Meadowridge on Saturday. See that report [here].

Noel also gave us feedback on the recent antenna work party held at the clubhouse on the 8th October - details [here].

We were shown the new CTARC name badges that the club hopes to have produced and have ready by the November meeting – details [here].

Details of the forthcoming November 2016 meeting (details here) and January 2017
meeting (details TBA) were mentioned.

We were all reminded to get in the nominations for the Len Wells Ham Spirit Trophy – details [here] – which must reach Dennis / ZS1AU by 31 October.

There was also a brief mention of a recent Memorandum of Understanding being drawn up between the SARL and ICASA.

The very successful Bring and Buy / Swop Shop was also announced and is discussed [here].

Then it was time for Paul to introduce John / ZS1PM, an electrical engineer (now retired) from UCT who has had a long and fascinating career, both in amateur radio and in the field of professional RF engineering.

John described his introduction to radio when a neighbour, Herbie Taylor / ZS1JK came on air with a signal sufficiently strong to blank out the green “magic eye” tube on his parent’s radiogram! This lead to a visit to Herbie and an introduction to the world of radio. In 1949, the CTARC was called the Cape Town Branch of the SARL and used to meet in the Cape Town YMCA Hall.

Through Herbie, John met Max Adler / ZS1ACD, who was a gifted musician and piano accordion player. John was so impressed by a performance given at the Hotel Cecil in Claremont that he took up lessons with Max and later joined his band of accordion players in Johannesburg, where he was to meet his future wife!

John described a visit as a schoolboy to the radio station in Milnerton, which was the radio communications receiver link to the UK. At the time it had five 100m tall masts with wire beam antennae. The transmitter station was a little further away at Klipheuwel. The link consisted then of just two duplex voice channels and an RTTY channel. The Milnerton receivers were 1930’s Marconi rigs with separate tuning controls for RF Stage, Oscillator and Mixer – none of this new-fangled ganged-tuning nonsense!

In those days, what with all the war surplus equipment still available, radio components were in plentiful supply. Certain companies foresaw the potential of the hobby market and Jack Twine started the Hamrad company. Later on he was joined by the Morris bothers and Hamrad moved to larger premises.

In those days, ham transmitters were home-made. 807 and 813 beam tetrodes, and 809 and 811 triodes were used. Antennas were most wire -  folded dipoles, long-wire and ground-plane verticals. There were few beam antennas in Cape Town then. When John moved to Constantia to a larger property, there was enough space for him to put up a 270 foot long wire  antenna. Later on in his talk, John was to show us his homebrew 100 mW crystal-controlled transceiver with which he was able to work Joburg – via Tippy Marais (ZS1CL)’s beam antenna!

1957 was a peak in the solar sunspot cycle - (a maximum that has never been  achieved since then) and correspondingly there was a great interest in amateur radio. John would work the Eastern Coast of the USA on the long path and have QSO’s with good signal strengths with just 50w of power into his LW antenna.

In those days, even before Springbok Radio came on the scene, there was just the “A” programme (English) and the “B” programme (Afrikaans). For a little variety, L. M. Radio would magically rise out of the static on 11.7 MHz in the early mornings in the summer months. Receivers were Hallicrafters SX28’s (which had been made in quantity for the war effort), Hammarlund, Eddystone, the legendary National HRO and, for those with the necessary folding stuff, the Collins 75A series, which were accurate down to 1kHz and stable enough for SSB (although most ham transmissions were on AM at the time).

John built a dual band double conversion receiver for 7 and 14 Mhz (21MHz was to only become available later). He also was building homebrew transmitters and made his first contact with the USA in 1954 using 50W. Later he was to acquire an enormous transmitter (christened “Big Bertha”!) that had been a beacon transmitter, which he converted to the ham bands. Sufficient was its output power that he could walk around the garden at 100 metres distance holding two fluorescent tubes that would light up! Prudently, Big Bertha’s usage was limited to occasional test transmissions.

A cubical quad antenna for 28 Mhz was used by John to work New Zealand with regular success.14Mhz contacts with New Zealand were more difficult.

When John graduated, he travelled to the UK and worked there, then, after a spell in Cape Town working for IMC he went to the National Institute for Telecommunications Research up in Johannesburg at Wits University. Working under Dr Hewitt, he met and worked with Dr Trevor Wadley. One of the first projects was an Ionosonde instrument, used to measure the height of the ionosphere at different frequencies thoughout a 24-hour cycle. The MUF (Maximum Unsable Frequency), (HPF) Highest Possible Frequency and OTF (Optimal Traffic Frequency) charts put out by the NITR and – extremely useful to radio amateurs – were published in Radio ZS for many years.

John then spoke about the Tellurometer, Dr Wadley’s invention (and a first for South Africa in the world) that was to revolutionise the practice of Surveying. Up until then, surveying was carried out by measuring angles and using Trigonometry to work out the distances between beacons.The Tellurometer measures the transit time of a (GHz) radio wave between two points. Making allowances for the speed of the wave through the medium, one can calculate the distance accurately.

In 1959/60, John worked on the first solid-state Tellurometer (you can appreciate how surveyors would have appreciated not having to lug “valve” equipment and associated large batteries up to mountain summits!). Throughout his talk, we were made aware of the gradual improvement of radio components, from bulky valves, through whiskery germanium transistors, through to silicon transistors, through to integrated circuits, with the consequent effects on the possibilities of miniaturisation. 


So too were there developments in accuracy and calibration. Initially, equipment was calibrated against the WWV time signal. Later on a Hewlett-Packard frequency counter at the NITR provided  accuracies in the order of 1 Hz at 20 MHz. While much of the ancilliary circuitry could become solid state, the source of GHz frequencies had to remain hollow-state - the Klystron (and its appropriately bulky power supplies) - for some time.

The Tellurometer is still very much in use to this day, though the technology has become far more portable. Many specialised variations have been developed for specific surveying applications.

John also touched briefly on the technology behind the legendary Wadley Loop, which was to revolutionise receiver tuning, stability and design methods, as illustrated in the Racal series of receivers.

After his talk, John kindly answered some questions from the floor, and then it was coffee, biscuits and the chance to peruse the items brought for sale or swop. All in all a great meeting. Thank you so much to John for his very informative talk, and to all others who attended and participated. We look forward to seeing you all at the November Meeting!



Paul / ZS1S opens the meeting and welcomes all

A well-attended meeting - and they kept on arriving!

Noel / ZS1FW gives his report-back on the JOTA event

Pauk introduces John / ZS1PM (on left)

John's talk provided a fascinating insight into the development of
radio in South Africa, for young and old alike

Above: "Big Bertha", John's massive transmitter that started off as a
beacon transmitter, and was later converted to the ham bands.

The late Trevor Wadley, inventor of the Wadley Loop
and the Tellurometer

John shows us his homebrew crystal-controlled transceiver

Afterwards, the chance to socialise and chat


Danny /  ZS1BL, with some of the UCT crowd who attended


   

Wednesday, 19 October 2016

CTARC Forthcoming Meeting - 22 Oct '16

The October 2016 Cape Town Amateur Radio Centre members meeting, (usually held on the fourth Saturday of each month), is on Saturday 22nd October, at 14h00, at the CTARC clubhouse in Rondebosch.

Directions to the CTARC clubhouse are [here].

At the meeting, John / ZS1PM will give us a talk about the exciting developments in electronics at the time when transistorised designs superseded those using valves (vacuum tubes). He will mention his work on the first transistorised Tellurometer, done under the guidance of Drs Hewitt and Wadley at NITR (National Institute for Telecommunications Research). Dr Wadley was the inventor of the Tellurometer, the “Wadley Loop”, and more.

We were privileged to hear John speak at the CTARC's Seventieth Anniversary luncheon held at the Wild Fig Restaurant in June this year.

We look forward to seeing you at the October Meeting!

CTARC Club Badge - 19 Oct '16

Announcing the CTARC club badge!

Show pride in your club and wear the new name badge. It's in stylish gold with black lettering and measures 50mm x 70mm wide. It has CAPE TOWN AMATEUR RADIO CENTRE, your CALLSIGN, your FIRST NAME and the CTARC LOGO. Ideal for club functions and anywhere hams get together.

Cost is R50-00, and payment must accompany your order.

Badge orders will be taken by Paul /  ZS1S at the October monthly meeting at the CTARC clubhouse, on Saturday 22 October at 14h00.

Alternatively, e-mail our club secretary, Anne (here), with your Callsign and First Name and proof of a R50-00 EFT into the CTARC's club account (details here). The e-mail subject line must please be "BADGE" and your CALL SIGN.

Badges will be ready for collection at the November montly meeting, our End-of-Year Function on Saturday 26 November at 12h00.

Tuesday, 18 October 2016

CTARC New Swops Service at Club Meetings - 18 Oct '16

Thanks to a suggestion from one of our members, the club is introducing a regular "Bring and Buy" sale at every monthly meeting held at our clubhouse.

Please feel free to bring a few surplus (amateur radio related) goods and place them on the side table together with your call sign, price and (if you wish) contact details. We are sure your equipment will generate great interest and will soon find a new home.

At the end of the meeting, please make sure you (or the new purchaser) remove the equipment, and take it home. Otherwise we will soon be unable to fit into our clubhouse!

Also please note that said transactions are done entirely at your own risk. Neither the Cape Town Amateur Radio Centre nor its committee can be held responsible for the safekeeping of said equipment. Nor will the committee enter into any negotiations or disputes between buyer and seller. The service is operated in good faith to allow radio amateurs to exchange or trade their surplus amateur radio equipment with each other.

Of course, we will continue to run our Swop Shop slot during our regular Sunday morning bulletins, and members are welcome to continue submitting radio-related equipment swops to appear in our bi-monthly newsletter, Ragchew. And we will also continue to hold our annual Mega-Fleamarket in March each year.

A report-back on the Swops aspect of our meeting of 22 October 2016 is [here].

Monday, 17 October 2016

CTARC Report-Back on JOTA Event - 17 Oct '16

In response to very positive feedback from last year's event, the CTARC put up a field station again for the JOTA weekend on Saturday 15th October 2016, at the Meadowridge Scout Hall, off Ladies Mile.

Noel /ZS1FW reports that the event was well-attended by Boy Scouts and Girl Guides, who responded with enthusiasm at the chance to make supervised contact on with others on HF and VHF. An HF wire antenna was erected and some contacts were made despite the rather disappointing solar figures.

A morse code key and oscillator were also set up at the station, which also generated great interest.

Thanks to all who assisted with the setup, running and take-down of the station afterwards.

Photos will be added here presently

Tuesday, 11 October 2016

CTARC Committee Meeting - 17 Oct '16

There will be a meeting for members of the CTARC committee, at 19h00 on Monday, 17 October 2016, at the CTARC Clubhouse.

Please diarise accordingly.

Sunday, 9 October 2016

CTARC Forthcoming JOTA Event - 14/16 Oct '16


This year the Cape Town Amateur Radio Centre will again run a field station for JOTA (Jamboree On The Air).

The JOTA event involves many thousands of members of the Scouts and Girl Guides association being given the opportunity to make supervised radio contacts with other Scouts and Girl Guides internationally, via radio amateur stations.

This year the CTARC will, as with last year, set up a field station at the Meadowridge Scout Hall. Noel /ZS1FW, who is managing this event for CTARC, envisages setting up the station on Friday afternoon, and operating on Saturday, taking the station down either on Saturday afternoon or Sunday.

Interested hams who would like to take part in this worthwhile and rewarding activity are please to contact Noel via the CTARC email address

CTARC Report-Back on Work Party - 8 Oct '16

At 10h00 on Saturday 8 October, members of the CTARC committee held a work party to tackle antenna and clubhouse matters. ZS1SA, ZS1FW, ZS1BL, ZS1PGC, ZS1ZD, ZR1HPC and ZS1MTF were present.

Paul / ZS1S and Matt / ZS1MTF tackled the main tower rotator and feedline, as well as the patch box inside the shack, which Paul spent a large part of the day repairing and rewiring.

Noel / ZS1FW and Nick / ZS1ZD assembled the Force-12 yagi antenna usually used for field day events. While it had been used on the Lighthouse Weekend event, it was noted then to have issues on 15m and 20m bands. So a thorough check was made on dimensions and with Pauls / ZS1PGC's RigExpert antenna analyser.

We were really assisted by ZS1PGC, (who gave a fascinating talk on the instrument at our September meeting). With his RigExpert analyser, he was able to provide accurate indications of SWR and points of resonance for that antenna across the bands for which it is designed. Danny and Noel made adjustments to the antenna and big improvements were made in the SWR. Extra rivets were added where needed and all elements were properly colour coded with tape.

We packed up at about 14h00 as the rain was about to happen. An interesting time was had fitting the newly-adjusted antenna elements back into the clubhouse...

Grateful thanks to all who assisted, to Peter for his great help with the RigExpert analyser, to Rob & Anne for the snacks and to Danny for the cooldrinks!

Hylton / ZR1HPC does a spot of vacuuming

Paul /ZS1S and Matt /ZS1MTF on the clubhouse roof

In the adjoining field, a team spreads out their own ground plane...

Paul works on the main mast's rotator, badly in need of a service

Noel lays assembles the club's Force-12 antenna on the lawn


Connecting up the driven elements of the beam

Peter /ZS1PGC takes readings on his RigExpert antenna analyser

ZS1MTF and ZS1S work on the feed-line to the main antenna

Paul /ZS1S works on the feed-lines coming into the shack

The Force-12 Antenna suspended above ground
to assist with the SWR readings

Noel /ZS1FW and Danny /ZS1BL fix rivets on the elements