Contents December 2001

1.Committee Members. 2. Secretaries Report 3. CTCSS

4.Disaster-Disaster-Why 5.Sales & Exchanges 6.Press Comments

7.A Bit of Humour 8.DX Radio Operations 9. Obituary

10. A question for You 11.Marconi Centenary Contest

M.A.R.T.S. Committee

Kevin Earl G8VJU President

Ken Gibbons G1JYT Vice-President

Cyril Atkins G7MPZ Chairperson

John Hale G3FTH Treasurer

Pauline Odle 2E1HRY Secretary

Brian Moran M1ALD Committee Member

George Morris G4INO Committee Member

Norman Speary M0CGJ Committee Member

Report from your Secretary

In case you have not noticed the decorations in the shops, since September, it will soon be Christmas. I cannot believe where this year has gone. I am very busy at this moment having two boys of my own and being connected to groups that organise things for children, so life goes into a bit of a whirl at this time of the year. One cold morning recently I met Len G4VRI walking along the road and he reminded me of this newsletter. I felt rather guilty afterwards that I had not given it an item a thought, so, I quickly put the computer on when I got home to type something, only to find the thing crashed on me! Modern technology is a wonderful thing.

The Committee would like to thank Len for all the work on organising and doing the newsletter for us. Please help by writing an article for him to print, items of interest for us to read on radio or social events.

On a similar note, I am keen to hear from any member who may be able to give us a half hour talk on an item of interest at our Friday meetings. If not yourself, maybe you know someone who can. I am sorry I cannot always attend the Friday meetings myself, I am afraid this is due to the pressures and demands of modern day family life, but I can always be contacted on 01634 316968.

I recently enjoyed the fish and chip supper, many thanks to the members who organised this event, and it was nice to meet so many members.

A reminder of two future events.

Christmas Party. Friday 21^st December. Cost £2.50 payable in advance.

Party hats to be worn, unless, members wish to entertain us.

Annual Dinner. Saturday 2^nd February 2002 Cost per ticket £20.00.

The venue this year is the Upchurch Golf Club.

Questions on either of these events please speak to George G4INO, payment for the later event need to be given to the treasurer John G3FTH.

I personally got interested in Amateur Radio by accident. I had to take my son Stephen to his school Radio club that was run by Gloria G3VUN. There was not enough time to take him, and get back in time to collect him, so, I sat in the class with him. Gloria had the radio on at the back of the classroom. On one occasion she was speaking to somebody on the radio, and said that she had children and adults wanting to talk and handed the microphone to me. After my initial reaction, I found myself talking to somebody who called himself Arthur M1BOS. Over the following weeks myself, Stephen and the rest of the class had several chats with Arthur. He gave us confidence to have a go at the Novice licence. After we managed to pass this exam Arthur was one of our first contacts and we spoke to him regularly on air. We were sad at the recent loss of Arthur, but he will always be remembered as Arthur M1BOS with his unique personality, Arthur was a real inspiration for me to have a go at Amateur Radio. Writing this article has prompted me to think it is about time for me to start studying for my full licence.

Your Committee would like to wish all M.A.R.T.S. members

A Happy Christmas and best wishes for the coming year.

Continuous Tone Controlled Squelch

System

Alan H Stanley GG1OMH

CTCSS stands for Continuous Tone Controlled Squelch System. Angus Tait, a New Zealand amateur, who started up ’ Tait Mobile Radio’ some thirty odd years ago, originally developed this. It was because, like the UK today, everyone shares frequencies. He came up with the idea that if a single Sub - Audible Tone was applied with each transmitter and corresponding receiver, then other users would not be heard without the correct tone.

These Sub-Audible Tones as they are referred to, are outside of the transmit and receive audio pass band for PMR (Private Mobile Radio) specifications, which happens to be 300 Hz to 2.4Khz . There are a basic 38 tones in very approximately 3Hz steps between 67 Hz and 250.3Hz. Therefore below 300 Hz is how the description of SUB AUDIO tones is arrived at.

When transmitting, a tone is added, say 103.5 Hz, to the transmitted microphone audio at a level which will not corrupt the speech, usually described as a “hum” if not set correctly. The normal setting for CTCSS is 10 to 15% of the system deviation. That is, on 25 Khz BAND WIDTH amateur radio with 4.8 Khz deviation a sub audio deviation of 480 Hz to 720 Hz. On the new amateur 12.5 Khz BAND WIDTH with a maximum deviation of 2.4 Khz it would be 240 Hz to 360 Hz.

Due to low deviation levels used, so as not to corrupt the transmitted audio, the receiver detector circuit is normally fed direct to the CTCSS detecting filter as well as the standard receive audio circuit. This is because the following audio circuit, amongst others, normally has a simple Resister/Capacity/Inductor filter to pass 300 Hz to 2.4 Khz audio frequencies on better quality radios designed for using CTCSS. The simplest type of circuit with CTCSS has a single transistor switch in the receiver audio path, which is controlled by the CTCSS detector circuit, which enables the switch when the correct recognized tone is received. Therefore with the agreed tone all is normal. Likewise when the incorrect tone is received, no receiver audio is heard.

On PMR repeater sites with multiple CTCSS frequencies and users, a CTCSS “control panel” allows a single (tone) user to access the repeater receiver and therefore retransmit its audio with CTCSS, whilst the acknowledged correct tone isused with a logic circuit to stop the other allocated tones working. This is done normally with timing circuits, usually programmed at two minutes to stop a frequent user “hogging” the repeater. If a user outstays his welcome, two minutes in this case, then that tone is blocked for say four minutes to allow other users to use the repeater/frequency. If the repeater is not busy the control panel all ows the first caller to continue in two-minute sections. Very simple, but it works.

The example with the amateur repeater, GB3KN, is to use the same tone on transmit and receive. Two CTCSS tone circuits are used independently, one for transmit and the other for receive. Some PMR repeaters use different tones for transmit and receive so that where a repeater may “hear” another repeaters mobile they do not block each other. Think of GB3KN and GB3VA who’s mobiles often access the Kent repeater.

Again with GB3KN if you enable CTCSS on transmit and receive you will only hear the mobile through audio and either a “G” for CTCSS receiver recognition, or “K”, no CTCSS , in morse code at the end of an over. You will not then hear any identification signals or GB3VA etc making for quieter use when in operation.

Sometimes CTCSS is referred to as a “tone code” or “Private Line, PL” and various other useless descriptions. It is not physically possible to make any form of code with only a single continuous frequency tone!

Disaster---Disaster---WHY ???

Jim Nolan G0HHQ

Many anxious relatives lined the quayside in New York on the 18^th of April 1912 as the liner “Carpathia” docked with 711 survivors from the ill-fated Titanic on board. A list of survivors had not been published and people were anxious for news .One of the first to climb the lowered gangway was Signor Marconi who immediately went to the radio office searching for his two operators. White Star Line had installed the Marconi Wireless Company’s equipment and personnel. One operator had been lost and the other, was helping the Carpathia’s sole operator to cope with the heavy list of radio messages. Out if 2.235 persons on board the Titanic, 1522 had perished.

With radio installed and experienced operators using it, many people must have asked WHY many more people were not rescued.

In a very busy shipping lane there must have been other ships close enough at hand to render assistance. There were but they didn’t make full use of their radios and didn’t hear the distress message.

The Carpathia with one radio operator, who was going off watch, thought he heard a distress message from the Titanic although he didn’t believe that the Titanic was sinking. Many other ships were reported later to have heard a distress call, but the Carpathia was the nearest. This was proved later not to be true as survivors in the lifeboats saw lights on the horizon.

The liner Californian was in the vicinity at the time and wonders WHY assistance wasn’t given as her deck officers reported seeing 8 distress rockets fired. Some thought that it was a jolly party on a passenger liner but made no attempt to investigate.

Much earlier, while steaming at 22 knots, radio reports were received warning that ice bergs had been sighted on the ice track ahead. One message from the Master of the steamer Msater was addressed directly to the Titanic’s Master stating that heavy pack ice and bergs had been sighted on the course line. The radio warning was not delivered to the bridge, as the operators were very busy attending to passenger radio messages.

It is the Common Practice of Seamen, when crossing the ice track in the dark to Stop the ship, Post extra lookouts, and have the engines on standby. One soon knows when a berg is approaching as the temperature drops dramatically. When a white cliff appears out of the gloom, a few turns of the propeller gives just enough steerage way to avoid it and any others near at hand.

During daylight hours a moderate speed is maintained with a good lookout to avoid Growlers ( smaller icebergs ) which can be very difficult to see when a heavy sea is running and white horses are breaking on the crests.

The Titanic’s Master was probably anxious to meet his deadline in New York. His managing director was a passenger on board. There was also considerable competition on the North Atlantic for mail contracts and passengers bookings between Cunard, White Star and several large continental companies, so, speed could have been a deciding factor.

Several lifeboats were sent off only partly filled. WHY? Apparently no one knew that a lifeboat should be filled while still hanging from the davits. Now the specified complement is clearly marked on the bow of the boat.No women or children from the steerage department were saved WHY??.Many questions were asked during the very full enquiry, which followed the disaster, and many new regulations were introduced, particularly where the use of radio was concerned when distress messages were heard.

I all the personnel involved at the time had realised the potential that radio had in the saving of life at sea, many of the 1522 who perished would have survived.

Jim G0HHQ would like to know

The following Depths were shown on ceramic tiles on the sides of a large indoor swimming pool in the ALGARVE. They are correct. Can you find the link, which makes sense to the numbers?

130M--------------43FT

190M--------------63FT

330M--------------11FT

07M--------------26FT

Sales & Exchanges

Members may wish to know that items for sale or exchange may be included in these columns, the Newsletter is published quarterly, March, June, September, December.

Items for inclusion should be with the editor before or during the last week of the preceding month.

Press Comments

FROM the Quantoxhead Parish Magazine.

“Mr P & MrsJ will talk on ‘Sweet Peas’ and there will be a pant swap.”

FROM the Wythenshawe World.

“At a ceremony this morning, it was announced that no less than four

Manchester parks have won the prestigious Green Fag award for

Good standards.”

From the Fosse Way Magazine Somerset.

“Wells Collectors Centre – old postcards – cigarette cards -

second-hand boobs…”

From Gt Shelford’s Free Church parish magazine, THE LINK:

“The church will host an evening of fine dining, superb entertainment and

gracious hostility.”

From Burnley Life.

“Never hold a baby in your arms when you are holding a sparkler. When

it is finished, put it in a bucket of cold water and leave it there.”

From the Rossett PTA News.

“New Parent Evening. This was an excellent night, with over 70 parents

attending and from the feedback we hope to shortly organise a sex-and-

drugs evening.”

From The Mirror

“ A CAR recycling centre in Berlin is hiring out sledge-hammers at

£1.60 an hour to people who want to get rid of their stress on old cars.

From Irish Times

“Russion aides accompanying President Putin to America paid there

hotel bills in cash – after exchanging four gold bars wrapped in a

paper bag at the Federal Reserve for $1 million.

From The Daily Telegraph

“A MECHANIC working on a Mercedes auctioned by the Customs

and Excise found £10,000 worth of cannabis hidden behind the

headlamps.

From The Times

“The application form for a security pass to the House of Commons

includes the question: “Have you ever been involved in terrorism ?

If so give details.”

From The Daily Telegraph

“LAMBETH council has booked a London hotel, at a cost of £16,0

for a Christmas party for 400 staff in its housing benefits department.

A bit of Humour

A professor creates a clone of himself and takes it to a press conference on the fifth floor of a hotel.

While giving his speech, the clone interrupts him with a stream of swear words. Finally, this gets too much for the professor and he tries to throw his clone out of the window. But his colleagues stop him in the nick of time and the police arrest him.

The charge? Trying to make an obscene clone fall.

“We are one of the last bastions of male chauvinism,” said the proud Pratt’s club owner, the Duke of Devonshire, at the Marsh Country Life awards.

“Woman are allowed only at our cocktail party. They react in three different ways. Some want nothing to do with it. Others say: ‘This is all very strange.’

“My favourite reaction is that of the elderly lady who said: ’My goodness, this place is like a nursery school for grown-up men.’”

DX Radio Operations

Courtesy of the R.S.G.B. News GB2RS

The rarest DXCC country in the world is on the air. North Korea, P5, from where only a handful of legitimate amateur radio contacts have ever been made, is being activated by Ed, P5/4L4FN. Ed works for the UN World Food Programme in Pyongyang and after a couple of years has been finally able to obtain verbal permission to operate amateur radio from North Korea. He is awaiting written permission, which it is hoped should be received around Christmas. For the time being Ed has 100 watts, SSB only, and a dipole. His preferred frequencies are 14.205 and 28.575 kHz and he works ‘split’, listening higher in frequency. His operating times are typically 1400 – 1500 and 2200 – 2300 UTC during the week.

Antoine, or Tony, 3D2AG, is expected to be active from Rotuma Island again from now until about the 10^th of January. The island is a separate DXCC entity from Fiji, and counts as OC—60 for the RSGB Islands on the Air awards.

SM5DIC travelled back to Burundi on the 17^th of November and will be there for around three months. He expects his 9U5D licence to be renewed. He plans to be active on the HF bands using all modes with 100 watts and a loop antenna, on 6 metres with a 3-element beam, and on 2 metres EME using

400 watts and a 17-element beam.

Morse Assessment News

Following the successful Morse Assessment session at RSGB HQ on the 7^th of November, when around 40 Class B licensees took their Assessments, allowing them to take out HF Foundation Licences from the 1^st of January next year, another ‘Morse Campaign’ took place at RSGB HQ last weekend.

On that occasion, 15 amateurs took the RSGB five-words-per-minute Morse code tests, allowing them to take out Class A licences. Those candidates who were not quite at the required standard for the five – word – per -minute test were given Morse Assessments, meaning that everybody went away with something.

The next Morse Assessments at RSGB HQ is on Friday 14^th of December, application forms can be obtained from the Amateur Radio Department at RSGB headquarters, or telephone 0870 904 7373, e-mail: ar.dept@rsgb.org.uk, also available on the RSGB web site.

The Russian Federation has told the International Telecommunications Union that it considers there are good reasons for the Amateur Service to continue with Morse code as a licence requirement for operation below 30MHz. It therefore intends to make no change to its domestic licence conditions whatever the outcome of the World Radio Conference in 2003.

International Museums Weekend 2002

Following the successful National Museums Weekend back in June, it has been decided that the event will run again in June next year. The difference this time is that the event has progressed to become an international event and it will therefore be known as the ‘International Museums Weekend 2002’.IMW2002 will take place over the weekend of the 15^th and 16^th of June 2002. Both clubs and individuals are welcome to take part from stations set up at their local museums. Full details of the 2001 event are on the Internet and a link can be found on the RSGB’s site at www.rsgb.org Details of the forthcoming IMW2002 are also on the web. Further details can be obtained by contacting the organiser, M1BYT.

World Amateur Radio Day 2002.

The IARU Administration Council met from 6^th to 8^th October in Quatemala City. The theme for World Amateur Radio Day, 18^th April 2002, was selected as ‘Amateur Radio: continuing innovation in communications technology’.

Stolen Equipment

The North Wakefield Radio Club has had a Yaesu FL-2100Z linear amplifier stolen. It is security marked and has a repair using non-standard components. If you are offered an FL-200Z and are not sure about its origin, please call Ken, G3SPX, on 01924824451.

Marconi Centenary Contest

This month marks the 100^th anniversary of that famous occasion when, on 12^th December 1901, Marconi received the letter ‘S’ in Morse code transmitted by his colleagues on the other side of the Atlantic. To celebrate, the RSGB has teamed up with the Radio Amateurs of Canada (RAC) to announce the Marconi Centenary Contest, which takes place on 29^th December 2001.

It should be pointed out the special short contest calls (eg G1A,M2B, GM3C, MW4D etc) are not valid for this contest.

Special Event News.

The Society of Newfoundland Radio Amateurs will be operating with the special callsign VO1S during the whole of December. The special event station commemorates the 100^th anniversary of the reception of the first trans-Atlantic signal by Marconi at Signal Hill in St John’s Newfoundland.

Solo Sailor Circumnavigation Latest.

We reported some weeks back, on the exploits of 77-year old David Clark KB6TAM, who was attempting to become the oldest person to sail solo around the world. The latest news is that David has now officially completed his round-the-world sail, although he does not plan to celebrate his accomplishment until he returns to his starting point in December. David arrived in the Bahamas last week, technically completing the circumnavigation that began in Fort Lauderdale, Florida, in December 1999. He is due back in Fort Lauderdale on the 7^th of December for a gala celebration. David has been using amateur radio to keep in touch with his family and friends during his epic journey. He regularly checks into the 20-metre ‘Seafarer’s Net on 1431kHz.

“ OBITUARY”

Arthur Thomas

M1BOS

Gloria G3VUN

I first met Arthur when I went to speak about MARTS at Ray Petri’s RAE class in Strood. Arthur joined MARTS soon after that and had been a member for over seven years when he died on October 5^th 2001. Earlier in life he had been a miner in Staffordshire and a roller skating instructor and champion. Now he felt a new energy to peruse the hobby of amateur radio.

Arthur worked long and hard for both his Novice and his B Licence. He was in his seventies and had never taken an examination in his life, but he finally succeeded in June 1997. The first entry in his log was on the 12^th July 1997: Doreen M0MTL, who has encouraged on their way many a radio amateur. His last entry was on the 19^th August, the last MARTS net he participated in.

Arthur was well known on the local nets, to local clubs and to amateurs in both Kent and Essex. One of Arthur’s hobbies was writing to penfrieends and his amateur radio activities extended his circle of friends still further. In May 2000 he won a construction prize for a receiver. His enthusiasm and determination gave much encouragement over the air to youngsters in Brompton-Westbrook Primary School Radio Club. He certainly contributed to promoting the hobby and was keen to pass on the knowledge he had gained. He has left many useful books to the MARTS library.

Arthur was a fine example to us all of sheer dedication and perseverance. I shall miss his company to and from MARTS every Friday and I know we already miss him as a regular member of the club and a frequent contributor to the Wednesday evening 2m net and other nets. His funeral was attended by a good number of his friends from MARTS. We extend our sympathies to his wife Sheila, his son and daughter and grandchildren

A Question for YOU

Cyril G7MPZ

1. To set the scene. Make an Oscillator, as outlined below.

The transformer is an Eagle LT 000 with the metal case removed. (A small transistor

Job). Put the whole thing into a small plastic box and fill it with epoxy resin with two wires out for the battery connections.

2. Make an amplifier.

The op/amp 1watt TD A7052 is useful for many applications. Make a coil on a plastic tube (an old pen), 1 ½ inches long to ¾ inches in diameter 34 swg wire, and connect to input, all these parts are available from our Local Electronic Suppliers.

3. What would these items be used for,“Reply’s in writing to your Club Chairperson