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BULLETIN ISSUED BY THE NCRTHER! ZCNES CF THE . P,C.BCX 1010
WIRELESS INSTITUTE CF AUSTRALIA TASYANTI/N DIVISICN LAUN CESTCN .
TAS., 7250
DECEMBER
Vel, 2 No, 9
REGISTERED AT G.P.C, HCBART
fer treansrissicn by post as
a pericdical, CATEGCRY D, PRICE 5¢
HAMFEST SPECIAL
|-,,.--—I4‘
It is a -lcasurc toc write a few lines for this our last issue for the ycar,
£thcugh the above linc could casily have rcad "It is with regret that I write
thesc few lines for this cur last issuc!!
The reascn being that we have run out of articles and in fact we spent the last
ccuplc cf days leccking threugh other publicatiens for suitablc naterial te cepy.
Tc date QRM has contained 7 pages cach menth, 3 of which are filled with mecting
nctes and notices written by the sanc people, Cur merbership is such that if every
nenber would fill onc page per ycar we could publish a 14 page bulletin cach rrnth,
Will YCU pleasc try and help us keep QM as it has been, on your docrstep every’
nonth and put pen to paper and write scmcthing for cur next issue,
(n behalf of the pecple assceiated with the preducticn of QRM and myself
I'd likc te wish all cur rcaders a very henrpy Christrmas and a prosperous New Yecer,
CUIN 73
JCHN VK75V
Fh R R R SRR RN RN
CCMING EVENTS
MEETINGS
Dee. 5th North Westem Zone — Le'zin's Hall, Ulverstcne
Dec, 8th Northern Zone ot the QTH of NCRM VKNR in the
forn of a DBBQ - Bring your cwn steaks and 807's
ALL WELGCCME! Bring your YL or XYL cr beth,
QTH -~ 69 Geergetown Read,
JANUARY No neeting in the North West
Jan, 12th Northerm Zonc - A.E.B. Rooms High Strect.
THE NEXT YRCS CLASS WILL DE CN FEDRUARY 24th - Scc next QRM
9th DECEMBER - RCSS HULL VHF CCNTEST
Q R M
BULLETIN CF NCRTHERV ZCNES W,I.A, TAS, DECEMBER, 1972
PAGE 2
SUNDAY NEWS BRCADCASTS
Now that this zcne is respensible for originating the 9-30an Sunday broadcast
we have a number cf adventagces:. ‘
- a local 2 metcr brecadcast
~ an AM 7Mes breadcast suitcd te transistor radics, dual wave radios cte,
- an inncdiate publicity channel fer locel nctes,
Help where you can by kecping a neote-pad handy, If you hear of something
ncwsworthy jot it down and hand on to 7KK soretime (or 7-30 Fridaysy on crenncl 4,
NCVEMBER MEETING
The Northern meccting was attended by thirty persons including 77ZLH and 7ZWK
from Hobart, We werc plcascd to welcore Gracre Crorpten, a member net scen very
often at cur mectings,
Mcst business transacted was rcutinc information - re satellite werking,
brcadcasts and nceting arrangerents, -
Slides werc shown by 7JV, 7PF and 7KK cnabling us to visit interstate and
cversces han shacks and rcrote radic sites within the state, Secing Mt, Read
under 2 fect of snow and an aerial vicw of channcl 3's transritter towsr.under
censtruction were twe unusual shets,
After the reeting Jehn 7JV aucticned a small quantity of gear donated by
various nerbers te the clubrecon fund, Bidding was ficrce and the trcasurcer inforns
e that the clubrecn acccunt was $68,00 better off,
DECEMBER MEETING
Decerber Northcrn meeting will be a barbecgue at Norm AWR and Anne Richardsen's
here, 6 Georgetown Read, Newnhan, Bring-UR-own refreshrients liquid and sclid
and the XYL, YL etc.
FCX HUNTS
The sceond fox hunt hcld this scascen on Nevember 24th was attended by nine
foxes.
7RR's idea didn't prove tee popular, With the help of an inside centact he
hicd his car in thc middle of a flcet of scrmi-trailcrs in a machinary firn's yard
and prcvided scric "suspeet! answers tc ecnfuse all and sundry,
It may be that ancther cffort will be held mid-January. Kecp an ear out,
F6 3 IR T H KRR
- RCN 3AKC worked VK6BE Tucsday 28th first on Cw ond on SSB with 5-5 sigs., The
VK6 becacen was alsc coning in 5.5,
RN
RNRHRK
VK6BE rust have rcally made use cf that opening as he worked VK5-MC, ZTW, DA, DK,
I RT3KK I ek
SRR
VK5 iC chris's 2 retre signals have been heard in U,S.4A, via the Mocn, Chris alsc
hcard both sidcs of a QSC betwecen VK3AIN and a W station,
AN RHHKK
Qo R M
DULLETTN CF NORTHERY ZCNES W.I.A4, TAS. DECEEmER,qco-
| PAGE 3
NORTH WESTERN ZCNE NOTES
Cur November nmeceting was well attended and numcrous natters of business were dealt
vith, Most of the cld-faithfuls wecrc present,
We heve been notified thet the call-sign of the beacon will havc tc be changed, £s
the alteration is frem a twe lctter to a three letter call, this has created
sonevhat of a problen to rodify the clceetronic keyer, However, the brainpower
of 7ZGR and 7ZLE arc working cn it end it shouldn't be tco long before the new
call is hcard, Bob was instrumintael in designing the criginel keyer and no doubt
will havc the answers te the present problen,
The writer has becen on lcave and is penning thesc notcs at Cressy, It has
buen very plcasing to hcar and work so many Northern beys pcer the repeater at
this Q. T.H,
Maybc yeu wont hcar so ruch of 7ZIE for a few weeks as Ian is very busy
working en his hecusc, The ('TH was sclccted for its sutlsfactory ooorutlon of
Channel 4 repcater end the housc is wrasped around he shack,. ..
We arc enxiocus tc know what thc dezens of wircs arc for radiating from thc shack
ell over the housec, Very intcrestingi
T72iQ hos completed his solid state car-phene and it scunds very goed Grehan,
Renember chans there will be no Jonuary rceting, Scc you first Tucsday in
Fchruary.
Cur zonc takcs this opnortunity of wishing a11 ORM rcaders thc cormlinents
of the scason and geood hamringi
VK7MX
3336 e R 63 I
s T 6L EN
STCLEN frem guards van at Reilton Railway Station on Monday Noverber 27th,
1672 cnc Pyc portaeble U H,F, transcciver on 168,25 MHz, Scrial Ne,335A, Also
cngraved in rany places with T.G. R,5.
If offcred wnit inform Policc, Tas, Govt, Railway or VKANR,
FFEI I I3
(ADVERT)
DRIAY 7zBY URGENTLY REQUIRES 3 CERAMIC 6/40 SCCKETS IN GCCD CCNDITICN -
STATE PRICE IF INY -
PHONE ~ WCRK 918288 EXT, 21
HCME 918218
ADDRESS CALL DBOCK,
QO R M
DULLETIN OF NORTHERY ZCNES W, I. L. TAS. DECEMDER, 1972
PAGE /4
TECHNICAL ARTICLES OF TNTEREST
I hopc this may bc the start of o series if I can keep it up, sirdlar tc
the Technical Topics of Pat Hawker G3VA I intend tc bI‘ln’ extracts of articlcs
fron rccent publicatiens,
WIRELESS WORLD SEPT, Part 1 of the WW desk calculator using a Texas 1802 NC
calculater chip, This chip is thc heart of the coleulator end ceentains rorc
than 6000 trensistors, All thc normal smell celculator functicns are available
with an 8 digit LED rcadout, A cormilete kit of parts is evailablc in the UK,
for £39,50, which is a very rcasonablc figurc,
SYNCHRCNCUS DETECTICK TN RADIC RIECE-TICN 1 by Pat Hawker,
A revicw of ncans of synchrenous detccticn leading up to thepresent dircet
conversion reccivers beccming rorc pcpular on the amteur bands,y Pat proniscs
in the sccond nart to introduce a systen called twe phasc quadraturc technicue
of deteeticn which gives a 7DD increcase in SAT rotic over a nornal product
cdctector,
RADIC RECEPTICN DEVELCPMENTS
New techniques described at en IL.E,R.F. cenference, Included is en articlc
cn noisc blankcrs with quite a few ncw idecas, onc of which is o ncw rethod of
blanking whcre by a dcelay circuit in the signal path is switched out to losc a
noisc spikc without actuclly »Hutting holcs in the wanted signal,
WIRELESS WCRLD OCT, 1972 Part 2 of the W/W calculator, end
Step by step construction using the available kit/with samplc exarples of
‘calculations, The corplete clrcuit shows ~nly 7 IC's including power sup»nlics and
shows how the calculator uscs a systen of tine divisicn rumltislexing of input
and outrut to the caleculator IC te save cn the number of lecads rcquirced,
RECEIVERS
IICISE SILENCER FCR AM
This uscs a LM372 IC as a noisc armlificr with its cwn AGC tc save to sct
the threshold, A gatc pulsc is derived from a comparator to give an output if
the neisc spikce is over the 100 per cent rodulaticn level, The gate nulsc is
uscd to gate the signel path gate of »ush pull FET's,
Fron 1y own cxpcricnce FET's rcelly work and I will try this circuit when
possible end belicve it will be possiblc to usc it on other rodes,
LII«EAR DD METER A simple design te reosure to -80DB,
The unit uscs twe cperatirnal arms 72741 in a cascaded switched amplificr into
o tcter circuit with ancther tue 72741's arrenged as o 1o pflrlthmc arplificr to
give a basic lincar O to 10 DB rxter scalc,
BRITISH ISLES VHF BEACCN SYSTEMS
A history of the develowrent of the becacons and the c¢ffect they have had
cn the increcasce of general activity on the VHF, VHF bands,
FRACTICAL ELECTRCNICS, July, August, Scptember se far,
THE P, E,CALCULATCR
This calculator will give sirdilar results te the W/W calecwlater but uscs
individucl 7400 scrics 1C's, a wholc 144 of thei, The cost will be neny tires
the W/W enc but the circuiting will be of intercst and if cnc were to build cnc
I'n surc you would have a hctter understonding of what gocs on.
ALPHANUMERICAL DISPLAYS FART 5, 6, 7.
Part 5 describes light enitting dicde displays (LED) and the fern they take,
Part 6 shows how LED displeays can be used and how a four Aigdit version uscs
o tinc sharing systen to save cn dececder anc packeszc leads,
Part 7 Cther types of displeays, Licuid crystel, det matrix, scven scgment
filanent, cathede ray tubc, scven scgrent scan,
H/M RADIC ACT, 1972 -~ High fmc;_ucncy synthesizer, 300 Khz te 10 Mhz, This is a
sirple generator not suiteble as a TX or RY cscillater scurce but as an accuratc
frcquency gencrator using IC's where thc, frequencey can be sct up by thumb whecl
switchcs,
0 R M
DULLETIN CF NCRTHER ZCNES W,I,A. TAS, DECEMBER, 1972
PAGE 5
73 SEPTEMIER 1072 ,
FREQUENCY SYNTHESIZER FCh2 I Parti
This synthos:Lzoris designed o teoke the place of TX snd RX crystals in a
veriety of MM sets tc give 145 to 148 MHz coverage in 5 Khz steps, This is
similar to what Bob 7ZRF ancd rysclf have been cdeveloping and part 2 with cirenits
is awsitcd with interest, This first part gives the theery ond applicaticon feor
usc on 2 M,
On the same subjcet cn page 106 is a writc up cn a cormercial unit at a
kit price of $130.00. ’
PLTER VK7PF
LETTER 0 THE EDITCD:
Dcar Sir, A
"The concisce Oxford dicticnary descrives FUOX and HUNT as follows:-
FOX: n.(Fon, Vixen, Alsc Bitch) A Red furrcd sherp sncuted vushy tailed quadruped
Preserved in England as a becast of chasc, Cunning....,fict craftily,
HINT: n, Hmting (Lit. & Fig.) Perscns hnting with a pack,....Pursuc wild animnls
ge.qa..‘SCOUI‘ (DiS'tricL)“
Since our last Fox Immt comnents have been madce abeut where certain parties hid
their vchicles. Trenslating the ebeve descrintions of FCX end HUNT I would think
that cnly crafty uvnderhended nethed ¢f concceling a transritter would be fair go,
If ever-we were celled unen tc uncarth an 11lcgel tramsrditter operating
egainst the Statc we cculd cxpect to have to work harder te find it,
Tut to be scrious perhass the Edd 'tor could lock up the rules as used on
the mainlend for fox hunting aad perhaps escic onc can orgenisc a goed mep and
ccrpass which can be handed o "chc fo;cto teke with him when he hides, New if
we could cnly get back to dirccticual hmts we really could have secne fun,
Pcrsonelly I dentt think 7L i1s a red farved, sharp-sncuted bushy tailed
quadruped of cither gender nor is therc any “ruth in the rarcur that I will
dress English stylc for the next hwnt i,c. Red coat, top hat, horn and horsc,
TALLY HCl CHAPS,
DE VK7NR.,
IT MAY BE o little latc but we do welcorie twe new calls to the VHF bandss
DERRICK VK7ZIM +vhc is active cn channcel B
STEPHEN VK7ZSE who will be hoard Shu.x. tly cn 6 nctres Fif,
B3INI H KK
KEVIN gotting rcady fer DX scascn overhaul cn ZMM first in Q@ ycars. Mntcnna
rotator, Bcams up on the tower and a bare wall ready tc take the contesit
certificates.,
DAL AT STI
TN TN N0
IS B30
M N TR N s W
A de
03
%
&
G ki
SULLETIN CF NCRTHER Z(NES W,I,... TAS, DECREMBER, 19772
PAGE 6
HAVII'G RECEIVED scmc corders rccently fer 1GL carnhoncs and converters we'll wait
enother week before pesting samc te give you the oopertunity to be in it, Let's
know your requircnents within o weck., The Zene deoces get a sroll discount tc beest
its funcs,
TWC METRE F.M, TRANSCEIVER KITS,
T 001 Twe Mutre F,M, Excitcr,
' Neminel H,T, 12 wvelts, Pruwer cuthut in cxeess of 1 watt at 13.5 wolts.
Crystal frequency multiplicd by 36, cepoblc of driving a OCEC 6//0 which can be
armlitude redulated, Deord Size 7N x N,
Price’1Bped tox.
S 002 Spcech Arplificr (i svit
T001)
Nerdnel H.T. I 12 velts, Digh Z input, Suit Ceramic Mie., Constant level
arplificr, Acriel C/C rclay for usc with receiver R 001, Dcard Size 7" x 1M,
Price $13,%0 Irc, Tox,
R 001 Two }Mctre F,M, Receiver,
Nerinal HoTe & 12 Volts, 20 b culeting at 0,3 uV signcl, I.F, sclcctivity
in 2 MHZ block filter, (Filter is rountcd & Pre-clligned), Dandwidth in excess of
I - 15 KHz, Current consurption is typically €0 ma ruted, 160 ma at full velure,
Excellnt cross roculotion, charocteristics, Mute circuit incorperated, Audic
cutput 4 watt nordnal, Beard Sizc 7" x AW,
Price 75,20 inc, tax if purchased
with othcr kits as a transceiver,
61,20 inc, tax purchased as a
separate iten,
X 001 Fivc Channcl CrystelDoard
Receive frequency sct trimmer capacitors, trensmit frecucncy sct trinm pots. Five
nosition rotary switch, Deard size 7" x 19/16",
Price 710,35 inc, tax,
Transceiver Case, (to suit above itens)
Includes speaker, knobs, socket for ricrephenc & R, F. Spacc for limiter
neter if require, Sizc 9" x 9N x 3N,
Price 517,98 inc., tax,
High nower R.F. Finals
F 002, Twelve watts sinirun at 13,5 wlts, Current Crain nominal 2.5
aIms,
T
Price $37.95 inec. tox wired & tested,
411 kits will be suonlicd wirced & tested for an additional chorge of 209,
C 001 430 1'Hz Crnverter,
Vominal H,T, 12 wlts, 4DB ncise figurc, Singlc cenversion to an I.B, frem 14
te 150 liHz, Bread bend, suitable fer T.V, Uscs crystal in the range 28 to 36 MHz
third cvertone, Dcard Soze 67 x 2bn,
Price $17.85 inc, tax, Crystal not included,
C 004 2 Metre Converter
F, amp Singlc
Nominal H,T, 12 velts, Lew ncise 2,5 ¢b FET, Cascede L,
ccnversion to an I, F. up to 30 MiHz, Uscs crystals in the range 30 to 45 MHz third
overtone, DBoard size 34" x 2N,
Price %14.00 inc, tax, Crystal not included,
C 003 61lictrc Converter
Yorinal H,T, 12 volts., FET cascodc R.F, art, Single conversicn to an I.F. wp
to 20 VHz., Uses third overtenc crystol in the renge 30 to 50 MHz., Doard sizc
3.1..!! % g.%.u'
Pricc 14,00 inec, tax, Crystal not included,
111 kits include all parts and casy tc fellow ster by step instructicng.
Q R M
BULLETIN COF NCRTHEIN ZONES W, I. A. TAS. DECRMBER, 1972
PAGE 7
CCURTESY GEELONG AMATEUR RADIC T,V. CLUB
YET /ANCTHER PRE-AMPLIFIFER
Velucs are given for the 28 nHz band, however by changing L1 & L2 to
rescnate at desired frequency, pre-ernp can be made te irmprove the performance
of any receiver on any band,
Suggested layout of P/C beard is shown actual sizc below
L1 15 tums L2 18 tums
C1 47 pf, c2 33 pf,
L1 & L2 wound closc spaccd on
neesid formers
ell components aveilable X stcck
Northern Zonc cquisnent store,
et AL e e— o+ 12V
JooK L Ol
‘;—C I' 9712
82 =
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= = /9
MPF 2] l 67 o
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