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BARSCOMDUNMOW

STEBBING

NOTLEY

RAYNE HALSTEAD

WITHAM

COLCHESTER

COGGESHALL

Monthly Communication of theBraintree and District Amateur Radio Society

GX3XG

G3XG G6BRH

BRAINTREE

October 2016ROTAWeekend

Setup For ActivityWeekend

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October 2016

Meeting ReportsGeoff, G1WRH

UPDATE !

On 5th Sept Edwin showed a specialepisode of TX Factor that took over18 months to make. This featuredThe King’s School in Ottery StMary, Devon (GB1OSM) makingcontact with Tim Peake.

UK astronaut Tim Peake KG5BVI /GB1SS

The school had competed with otherUK schools to be one of ten luckyones to be able to make this amateurradio link up.

The early stages of the video showthe school’s enthusiastic scienceteacher guiding a class in theconstruction of basic radioreceivers. After the school has beenchosen, students are invited tosuggest questions to ask Tim, and a

varied selection are chosen. TheARISS team arrive at the school toset up a radio uplink and radio andvisual downlink with the ISS.

What is ARISS?

ARISS is an internationaleducational outreach programpartnering the volunteer support andleadership from AMSAT and IARUsocieties around the world withthe ISS space Cont.d on p4

Contents Meeting Reports ..…..………. 2 Activity Weekend .…………. 5 DIY Doublet ……………….. 7 Club Meetings and Nets ….… 8 Chairman’s Chat ……………. 9 Ramblings…………………. .. 9 BNC Connectors …………… 12 Rallies ……………………… 13 Contests …………………….. 14 Committee Info ……..…… .... 14 Club Info …………………… 15

. . . . . 6

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October 2016agencies partners. ARISS offers anopportunity for students toexperience the excitement ofAmateur Radio by talking directlywith crew members on-board theInternational Space Station.Teachers, parents and communitiessee, first hand, how Amateur Radioand crew members on ISS canenergize youngsters’ interest inscience, technology, and learning.

Questions being posed to TimPeake on the ISS.

A number of members commentedon how satisfying it was to see suchenthusiastic and engaged youngpeople.

The latter part of the meetingrevolved around arrangements forthe forthcoming ROTA.

The 19th was an operating eveningand members arrived to find that atrap dipole had been erected overthe club house. The two club radios

were in use, and Howard broughtalong his Icom 7300 and it wasmost interesting to see this SDRradio running side by side with theclub’s 746 on its more traditionalplatform. Neil brought along hishandheld DMR radio pre-programmed to repeaters in theregion and this was attached to thecollinear on the club house roof.After some frustration at nothaving any of his calls returned,Neil finally made a contact throughthe Clacton DMR repeater, via asecond repeater in the EastMidlands to an amateur in Dudley.Hot on the tail of this was a secondcontact in Essex. A handful ofcontacts were made on the clubradios using the GX3XG callsign.

Editorial VacancyThe current editor is standingdown, at the latest after theFebruary edition of Barscom.

Anyone interested in taking overshould contact the committee assoon as possible. The new editorcan take over immediately, orfrom a future date.

Assistance will be given duringthe hand-over period but thecurrent editor will not continueafter this time.

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October 2016

The club’s annual field event washeld over the three days of theAugust Bank Holiday, courtesy ofJohn and Rosemary in theirPaddock. John and Edwin assistedby Tony put up the main antennasand the marquee in advance of theweekend making everything readyfor operators.

Description of antennas and detailsof transceivers

1. G8KW trap dipole

2. Edwin’s 40m/20m dipole

3. Dual bander X30

4. Derek’s 40m loop (Monday)

5. Club Icom 746 and Yaesu 897, and Howard’s Icom 7300 (Sunday)

6. Clansman 320 HF (Monday)

7. Geoff’s 20m ¼ wave vertical with radials & Elecraft KX3 (Monday)

8. Dave (out of shot) working HF mobile from car

9. Also in use (not labelled) the club’s two mobile masts

Twenty members, partners andguests were in attendance manyvisiting on more than one day. Weenjoyed glorious weather, but therewas much QRM on the Saturday,mainly from storms, and a coupleof stations were heard closing downbecause of lightening approachingand passing over them.

The equipment list above shows thediversity of equipment in use, andJohn was on hand to help with anyrunning repairs in his workshop.Edwin tuned his antenna using hisMFJ antenna analyser and Dave didthe rounds of the field tuning

Cont.d overleaf

4 2 5 3 6 1 7 8

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October 2016antennas where beneficial to users.On Sunday Howard demonstratedhis IC 7300 radio and reported“making contact with two specialevent stations: One water pumpingstation and a windmill, but the bandconditions were quite strange so nota lot of contacts were made. Therewas a lot of interest in the radio andmembers were impressed with itscapabilities considering itscompetitive price level”. Almost atthe opposite end of the spectrum asregards radios, contacts on 60m and20m were made on the Clansmanwith its own whip antenna.

Neil operating the Clansmanremotely (assisted by Toffee)

Over forty stations were contactedincluding seven Eastern Europeancountries, the Netherlands and anumber of UK special event

stations. I was impressed thatMM0PAI/P was coming through5/9 from Uist on my KX3, butwhilst John was able to returncontact at 100 Watt on the trapdipole, my 10 Watts and portablevertical could not get back. Derekproved his homebrew 40m loop byexcellent contacts with Macedoniaand Greece.

There must have been at least 200man hours of radio activity in everypossible permutation and thanks toour hosts 100 cups of tea and coffeeconsumed, as well as generoushelpings of the traditional breadpudding from Dave.

Edwin and Jenny stayed on after theweekend and worked together withJohn and Jenny to return thepaddock to a semblance of order, soparticular thanks to them.

Club Equipment

You can borrow the club’s AerialAnalyser and the Morse Tutor(Less Battery) for a small weeklyfee..Ask one of the Committee forinformation

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October 2016

Back in the early summer I spentsome time evaluating my newhomebrew doublet aerial. It’s a halfwave on 40m at the moment but thismight change. I don’t have 20m ofspace to accommodate it so a metreor so at either end is dangling downat the moment! It’s up at about 10m.I’m feeding it with 300 ohmladderline to a 4:1 Balun just

outside theshack, followedby a short lengthof coax to aDaiwa CNW-

419 matching unit. Opinions aredivided on whether a 1:1 or 4:1balun is best but after trimming thelength of the ladderline I can get agood match on all bands 40m to 6m.Does that mean it’s actuallyradiating? Well the below areconfirmed QSOs though I’ve alsoheard India, Chile, Japan andIndonesia all with BIG pile-ups!

DIY Doublet Aerial and a 6m openingMike, G8DJO

Date BAND CALL COMMENT COUNTRY DISTANCEJun27 40m MM0UDI/P Scotland 618.62224 40m G0AYZ qrp 5Watts Gosport 171.94822 20m J6/KG4ZXN USA 7197.58622 20m KI4PAQ USA 7197.58616 20m 4L7D Georgia 3369.34716 20m EU1KY Belarus 1857.32915 20m SV1FJF Greece 2130.51814 40m 4JF1EU 4J3DJ home call Azerbaijan 3759.64311 40m EJ7NET IOTA EU 121 Tory Island Ireland 602.09911 20m SV2HJQ Greece 2130.51811 20m LZ425STA Bulgaria 2116.70010 20m A41PG Oman 5908.33110 20m NP3LY Puerto Rico 6875.344May28 20m PR8ZX Brazil 8778.18426 20m PH9HB/AM @ 41,000ft above Gurnsey 308.922

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October 2016On 29th June, there was a 6m opening and to my surprise I worked:

Date BAND CALL COMMENT COUNTRY29 6m EA5IDQ Spain29 6m EI8GS Ireland29 6m EA3EVL Spain29 6m EA1DR Spain29 6m YT3N Serbia29 6m EA6ALW Balearic Is.29 6m EA1VM QSB Spain29 6m EA1DVI Spain29 6m CT1GVN Portugal29 6m EA1CEZ Spain29 6m EA5/DL5EO Spain29 6m IZ8HUJ JN70VP Italy

Clearly not the best DX in the world but the aerial is is working and I willcontinue to use it as a replacement for the half size G5RV I previously had.

Oct3 JOTA Planning,

DRM Radio check over Pt 310 Club 2m Net17 Derek Mayes G3MMA24 Club 2m Net

Nov7 Surplus equipment sale.14 Club 2m Net21 Keith Haynes G3WRO RGM28 Club 2m Net

Dec5 Christmas social.12 Club 2m Net19 Natter evening.26 Club 2m Net

Talks by members on almost anysubject are welcome. Pleasecontact the Secretary to arrange adate.

Club Net - 08.00 pm local time2 Meters (S15) (145.375 MHz)

Club Meetings, Activities and Nets

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October 2016

Summer camp has now gone, thiswas one of the best camps for a longwhile. The weather was very kindto us, and it was well attended, withlots of experiments going on andsome good contacts.

We now look forward to Railwayson The Air, with Thomas the Tankin attendance.

Jota also coming up in October15th-16th, at Castle Hedinghamscout hut.

This will be our last Special eventthis year.

We have two interesting eveningsbefore the end of this year. The first,A presentation by Derek Mayesabout his time in Thailand. Thesecond a visit from the RSGBregional manager Keith Haynes.

We are now planning next yearsevening program, some differentthoughts for meetings, if you haveany thoughts for meetings, pleaselet Edwin know.

That’s all for this month

Best 73’s

Chairman’s ChatJohn, M5AJB

The Marconi monument at AlumBay on the Isle of Wight marks thesite where Guglielmo Marconi andhis British collaborators carried outfrom 6th Dec 1897 to 26th May 1900a series of experiments whichconstituted some of the moreimportant phases of their earlier

Ramblings from theIsle of Wight

Geoff, G1WRH

Cont.d overleaf

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October 2016pioneer work in the development ofwireless communication of allkinds…A lot of words, but that’swhat it says on one side.

Marconi’s personal achievementsfrom the Needles are not actuallydetailed on the monument, which isa matter of some regret. However,the Alum Bay publicity states that“In early December 1897, toinvestigate and experiment withtransmission to ships at sea,Guglielmo Marconi set up hisrevolutionary wireless equipment inthe Royal Needles Hotel, aboveAlum Bay, and sent the very firstwireless transmission.

A huge 168 feet high mast was setup outside the hotel and over thenext couple of years Marconiconducted ever more complexexperiments with wirelesstransmissions. In 1898 messageswere received from Marconi atQueen Victoria's Osborne Houseand on the royal yacht.

Little now remains of Marconi'sexperimental stations, as the hoteland masts have long since gone.However, a monument to himstands on the cliff top within TheNeedles and information lecternsprovide a detailed history of radio,

Marconi and the role played byAlum Bay.”

Elsewhere I have researched “… byMarch 1897, Marconi hadtransmitted Morse code signals overa distance of 3.7  miles acrossSalisbury Plain. On 13 May 1897he sent the world’s first wirelesscommunication over open sea at thesame distance this time over theopen water of the Bristol Channel,and then he immediately relocatedto the Somerset coast and stretchedthe range to 9.9 miles.

Well, now I’m a bit confused…firsttransmission over water from theNeedles, or across the BristolChannel? But never mind, themonument adds an air of gravitas tothe fairground atmosphere of thesite, and gives reason for theexistence of “The recentlyrefurbished Marconi’s Bar whichalso provides a contemporarysetting to enjoy a light bite andcoffee set in the birth place ofmodern communications.” …so itsays.

I took my /P equipment along withme on holiday, but unfortunatelyafter a century and a bit sadly couldnot emulate Marconi.

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October 2016

G1WRH working /P

For over an hour I was jigglingabout with a patch lead which I hadhurriedly made up before leavinghome to make a connection betweenmy transceiver, a well worn pre-loved Elecraft KX3 and antenna. Ihad tested it with a meter and it hadbeen ok, but on site I could receivenothing. After some head scratchingand unfortunately without havingbrought along a multi meter I putout a couple of CQ calls but gotwarning beeps from my transceiver.Fortunately I had a 20 foot coaxcoiled up in my boot, and Iconnected that in place of theshorter lead. Working from thesouth coast of the I o W with a hillrange behind me, but with the opensea in front I was soon picking uponly French stations on 20m SSBthrough my Super Antenna verticalwith just the one ¼ wave radial. Butwith a maximum of 10 Watts output

and conditions fading and withundesirable losses through thelength of the cable I could notcompete with more powerful Fstations talking amongstthemselves.

When I tested the failed lead athome I found that I had cut thedielectric (inner insulator) too shortand caused an intermittent fault.Part of the definition of the hobbyof amateur radio is “wirelessexperimentation” and my earlyattempt at /P falls into this category.I already have a design in hand foran improved 20m antenna using a 5metre stainless steel telescopic whipwith numerous multi directionalradials, to be tested at SummerCamp over the bank holidayweekend. Also I have learned tofully test kit before setting off, andto take a basic tool kit and suitablespare leads with me when operatingaway from home.

Railways on the Air

A report on this willappear next month.

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October 2016

BNC Connector ImpedancesIan, G8MKN

Some of you may have bought oldBNC connector leads at Junk Salesand not thought as to whether theyare 50 or 75 Ohm impedance.

The standard used by every majorconnector manufacturer for BNC‘sboth 50 Ohm and 75 Ohm is MIL-C-39012. This specification coversall of the interface dimensions of theconnector (the parts that mate withanother BNC), the centre pin of themale/female, ferrule fingers, andlength of the connector etc. It doesnot specify things like insulatormaterial, size, shape, crimpdimensions, etc. These details areleft to the manufacturer’s discretion.

The centre pin of the male BNC isspecified at .053” +/- .001 at theinterface point to the female. Theferrule fingers are .193” +/- .001internal diameter, at the interfaceregion, and .390” at the crimpregion. The .053” centre pin will

result in a 75 Ohm impedancein the ferrule finger regionwithout additional dielectricmaterial, and 50 Ohms withthe addition of dielectric

(Teflon).

The quickest way to spot a non 75Ohm BNC is to look for insulatormaterial around the centreconductor or ferrule finger of theconnector. In the late 60’s, beforethe invention of compounds likeUltem and Teflon, the easiest wayto change the impedance of theBNC to 75 Ohms was to drop thecentre pin diameter to compensatefor the added dielectric material.The problem is that the smaller pindid not properly fit into 50 Ohmconnectors using the .053” centrepin opening, and worse, the female75 Ohm units were blown out by thelarger .053” interface pin of the50  Ohm connector. Fortunately,good science and engineering sincethat time has done away with thispractice, and standardized on the.053” interface centre pin.

Reference: CommScope, Inc

Club Equipment

You can borrow the club’s Aerial Analyser for only £1/day and the MorseTutor (Less Battery) for 50p/2-week session.Ask one of the Committee for information

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October 2016

2 OCTOBERBRITISH VINTAGE WIRELESSSOCIETY AUTO JUMBLEThe Angel Leisure Centre,Tonbridge, Kent TN9 1SF.For bookings/enquiries please ring01892 540 022 (8pm to 9pm only).[www.audiojumble.co.uk].

BLACKWOOD ARS RALLYNewport. Details available fromMike Rackham, GW4JKV on01495 226 149 or by email torackhamone@aol.com.

7-9 OCTOBERRSGB CONVENTIONKent’s Hill Park Training andConference Centre, Milton Keynes,[www.rsgbevents.org].

9 OCTOBERHORNSEA AMATEUR RADIORALLY Yorkshire Details fromRick, MØCZR, on 01964 533 712,or email R106221@aol.com.

HACK GREEN BUNKER RALLYNantwich, Cheshire, CW5 8AL.Further details from Lucy on01270 623 353 or by email toL u c y @ h a c k g r e e n . c o . u k .[www.hackgreen.co.uk].

16 OCTOBERHOLSWORTHY RADIO RALLYDevon.Details from Howard, MØMYB byemail to M0OMC@yahoo.co.uk.

22 OCTOBERCARRICKFERGUS AMATEURRADIO GROUP RADIO RALLYDetails from Tim, MIØTBL by emailto carg@hotmail.co.uk[www.radioclubs.net/carg].

23 OCTOBERGALASHIELS RALLYDetails from Jim, GM7LUN, on01896 850 245, or emailgm7lun@qsl.net.

NORTH WALES RALLY –CANCELLED

Rallies

BADARS Club LibraryWe hold a collection of books and DVDs that feature electronic construction,operation, the history of radio, shortwave listening and other forms oftechnology to do with radio, including the ‘Secret’ work carried-out byamateurs during the war years..

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October 2016

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CommitteeChairman: John, M5AJB 01787 460947 1 Ross Cottage, Southey Green

Secretary/Membership Secretary: Edwin, GØLPO 01376 324031 42 Panfield Lane, Braintree,

Treasurer: Neville, G8CDG

Ordinary Members: Geoff, G1WRH 01376 323223 07745 569564 Melvin, GØEMK

HF

Oct2 0700-1900 DX Contest HFChampionship12 1900-2000 80m Club SprintCW16 1900-2030 RoLo CW HFChampionship27 1900-2000 80m Club SprintSSB

Nov5 1700-2100 InternationalAutumn Sprint SSB9 2000-2100 80m Club SprintSSB12 2000-2300 Club Calls(1.8MHz AFS) AFS Super League19 1900-2300 2nd 1.8MHz

VHF

Oct1 1400-2200 1.2GHz Trophy /2.3GHz Trophy VHFChampionship1/2 1400-1400 Oct 432MHz-248GHz Contest16 0900-1300 50MHz AFSContest AFS Super LeagueNov5/6 1400-1400 144MHz CWMarconi VHF CW ChampionshipDec4 1000-1600 144MHz AFS AFSSuper League26-29 1400-160050/70/144/432MHz ChristmasCumulatives Contest

Contests

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Braintree and District Amateur Radio SocietyThe club meets every 1st and 3rd

Monday of the month at BraintreeHockey Club, Church Street,Bocking. Doors open at 7.30 pm,meetings run from 8 pm to 10 pm.

Membership is £16 annually;Senior members (State Retirementage) and Junior members, under18, pay £10. A door fee of £1 isalso payable at each meeting bymembers and visitors.

BARSCOM is sent to members bye-mail on the first of the month;paper copies are available at thefirst meeting of the month (pluspostage if appropriate).

Members may sell or exchangeequipment etc. before the start ofeach meeting, during the tea/coffeebreak and may advertise inBARSCOM free of charge.

Some members have had problemswith UHF and BZ access, and as aresult the Club Net will nowoperate on 2  metres only. Thisshould make it easier for allmembers to remember thefrequency, and for non-membersto find the net. The net will useV30 (S15) 145.375 MHz, starting20.00 hrs local time on the 2nd, 4th,and 5th Mondays of each month.

Please send articles for publication to i.wager@kaladel.net.

The deadline for submissions for the next edition is 25th of the month. Items will be published in the first

available edition subject to space availability.

For more information and pictures of events and projects seeour Web Site at www.badars.co.uk

Please contact our Chairman for details about commercialadverts.

BARSCOM Editor (Ian, G8MKN) © BADARS 2016 - E.& O.E.

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