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TASMANIAN DIVISION
SECEfEBER 1965 BOX 851J, &. P. 0., HOBART
MONTHLY BULLETIN PRICE 6d.
PRESIDENT: Mr. T. Alien TREASURER: Mr. V. F. Dore SECRETAEY: Mr. K. Spiegel
VK7A1 VK7JD VK7KS
Registered, at &.P. O., Ho'bart, for transmission by post as a periodical.
EDITORIAL
As the -twiligh-fc of 1965 approaches and the Fes'bive Season commences, mankind, all
over -the world extends . -bhe hand of greeting to his fellow man»
Unfortunately, due (IUQ to differences in racial, religious, poliiical and educa-tion
al beliefs mankind has not as yet achievsd -the sublime s-ta-te of mutual agreement. Ye-fc at
this time of -the year he gree-ts his fellov.' nan in terms of friendship ooupled with -fche
joyous fQstivi-fci. es of this annual period.
Amateur- Radio possesses tho unique q.uali-fcy of extending the hand of friendship.
,
-bo all corners of -the globe - ignoring the' differences of color, r-ice, or creed aiid •
a-t all times of the year» In -this purpose alone a small segaent of the worlcLs population
is helping -fco foster and. aaintain a, decent and consistan.t s-fc-andard of livingo
To those who are genuinely con'br'ibu'fcing to this cause, and. who sincerely
relieve in it, •t\:. •;. :;.•. :.. s:- ..•.... ',. 1,- I... ::. :"'.•;. -;.. - ;',:•.. • : I eBE-bend greetings for a very Happy Xmas
and a joyoiis New Year -to you and. your families and may all' that you. strive for Tsocome
a reality in 1. 9660
Ted VEC7EB.
MEETISGS FOR SECSffiER :
DECEMBER 1 Headq.uarters General Meeting, "147 Liverpool S-b., Ho'bart. £000 hours
7 North Vfe stern Zone, Lakin's Hall, Ulvers-tone. 2000 hours
10 CTorthsrn Zone, Adult Education Centre, 51 York S-fc., Lau.nccs-bon. 2000 hou.rs.
15 Headquarters V» H. F. Groap. 2000 hou.rs.
20 Council Meeting, Ho'b-art. 1930 hours»
WEDDIKG BELLS
Gongra-fcula-fcions to Davi-d, VK7ZAY and his wife to be, Audrey, whose wedding
is "fcobe solomnised a-b Holy Trinity Church on Saturday 20th Foyember. Best wishes are
extended on behalf of Council and the Division.
The Mon-fchly Bulletin of the Wireless Ins-fcitu-fce of Aus-fcralia
December 1-i6 Tasmanian Division Pa e 2»
..-BEAD UTTERS.. &E!TERA'L, MEETIJG ; . '• •':
TIie Lec-fcurQ in-tended for--the Seoember meeting o£ •bh© Division shall be
" Radio :-bo-'th'g-Sesoue'Tn'MGtQOrology " Tsy Ife-. H. G. Bond BSo»
Mr. Bond is the Regional Director of the TasDanian Bureaa of Meteorology. In th&s capacity
Ifc. Bond ia asking .'for the GO- .- . operation of all Radio ;jna-teurs in-'a v/orld wide
Me-beorologics'J. 'b.al.oon -tracking pro jec-t. - an outline shall also be given on some of -fche
Radio aids used in weather' forecasting.
CONGRATULATION
To ^'mne on o'b-taining her full call sign - there is no excuse now Mkeo
My spies -tell ns -there could bo a.few -more £ull.. e. alls coming up in. 1966
PEDER^iL COmTCUiLOR . . ......
' Honiina.tions' are invited-for. '-the positi-on of. Fed.eraI Counoilloro liTomina-bio&s •bo
be submi-fcted-'-to Couricil 'by December 13-8i» 1^65y ancL are to be signed, by Proposer, Seoondgr
and endorse. d. by- the I'ToiTi-i. nee... 3'p-te all parties are •to 'be financial lisenoees.
Please show'a li-t-fcle in-terss-b in your Division, your presen-fc Federal Councillor, YK7EJ
'because of family and basinsss reasons would welcome a newcoaer to -this impor-ban-fc
position^
R03S HULL £'IE"iroRTAL V., E_._^__CQLT TE5T_1 6-5 - 66
The Federal Csntest Corarait-bee of the Wireless Ingti-tuto of Australia invites all Aus-b -
ralian and Over seas A^a-teur's and Shor-t Wave Listeners to pa.r-fcicipa-fce in this annual contesl;
which is held -uo perpe-fcua-te -fche memory of Ross •Hu. ll whose interest in V. HoF* did much to
advanae the az"Ca
Date of Contest ; From 1401 hrs GMT 11 <h December 1965 to 1359 hrs GMT 16-fch. January 1966.
Object. s s Aust. ralian jfjna-beiu's vdll endeavour to oontac-fc as many o-ther Affla'betirs in Atistralia
and Overseas under the condi'uio'ns'of'the cohtesto
Durati. on s- I^ny consQGutive, 216 hours (" 9 d'ays ) within the dates aen-fcioned abovey this
period, to ~be at 'the choioe' of the opera-boro
Refer your copy of " Am.a-teur Radio "for further par--biGul£irs»
FOR SALE
Hallicraf'bsrs SX 25 CorBi?.um. 3a-bion Receiver, 240 Vol-fc. o 1500ko - 30raGS with
liandbook. Good condi-fciono In-fceros-ted parties con-baot YK7RM who will be only -boo .. plgagsd.
to deraon.stra-te -tho performance of this fine receiver. Purchase negotiations -to'be made
direct v/ith Rape ( VKTRIil). ••
Ths Monthly Bulletin of -the V/ireless Ins.-ti-tute of • Australia "
Decerat. er. 1. 6. . ... •• ---•'EasTaani'an. 'Di'vision Pa e 3.
R. S. G. B. HAITSBOOK5
More copies of -this fine book are due "bo arrive soon.. If you. has-e
not o'btained a copy ye-t please advise the Hon. Seco There vri. il .be only a liai-bed number
available so don't say you werent v/arned - the nuatiers obtained for this Division alone
speak for- -the value of -this fine edi-bion. Place ypur order now and you wont be disappoi
n-bedo
MOBILE TRAN. SCEIVERS
Twen.-ty four ( 24. ) ao'bile 1;ranscsiver's a-ce coining to hand. from aainland sources.
For reasons beyond th control of Coancil and -bho Gonimi-btee concerned i-b is regretted
-tha-t sone nenlsers have had. -Lo wait for their unit a li-b-fcle longer than inton^ed.
Every effort has "been aade -bo roc-fcify -the si-bu. a'tion despite soae suggestions t.o the
contrary. If there should be any furtlier doub-bs I woLOd respec-tfully sugges'-fc bringing
tlion foreward. a-fc •tho nee ting e.t tho Harafesto
-SLOW MORSE TR/JTSIIISSIOIS
Listen -bo the Tsroadoas-t for possi'ble coanencing cLa-fce for slow C. W. -bransraission
on -the fre'.quency 52. 2 Eios»-Tlr-ie and days proposed 2000 hoars Sundays, Tuesdays and
Thursdays* Again raay I m&lce a sugges-fcion. The opera-bor vrould like acknov/ledg raents
a.1 -the end. of each -br?.nsaission.. Reaeraber he is good. enough -to give his -time pleaso
don-fc let him think, it is being wasted^
TECEtUC^Jj by Greg John.••'•"n Part 1.
Vfell ye Ed has poiinced sn. Q. coerced yours truly in-to inflic-bing -tl-Le following on
•the unsuspecting clan -to which he de.votes rauch of his sp^ire -time. Now, as -the hea.ding
will suggest we-talked too much abou-fc the low noise fru-i-fcs of a'bou-t 12 months endeavour
-thus giving -the Ed his chance -to pounce.
The origonal scheme was to oons-truo-fc a self contained " Gel. oso " type. fron-t end with low
noise figures,, and .-fche circuit, shovm represen-ts -thG"end. " ( for- a'bou-fc a month anyway
the -tine spon-t raos-b profitably the animal
produc-t of -fclis projec-bo For a change, was as
cer-b. ainly perforn s beyond all my expecta-tions. ( Agreed - hence small spacing, give -the
lads someihing -bo chew over during Xmas -. Ed. )
I-fc v/ilt be seen -tha-fc -the soaewha-fc unusual lino up includes a 6ES8 series casoode
RF s-tage, 12AT? " Like new llixer" with a 604 variable oscillator producing frequencies
appropria-te -to a fixed- IF of 3. 5 racs for each band. As hi ^ impedance ou-fcpu-b was
desired, in my case -the out put was taken froa an R. P. O. ·throu.gh a . 01 ^uf condenser
from -the 12AT? second pla. te. For,. low iaped-anee out. pu-fc subs ti-but ion of an IF Iransformor
for th o EF clioke and taking ou. tpu-b from a link -there, could'be oasilyniade.
Ml -tuned circui-fcs ( oscillator excep-tecL ) are 'broad Tsanded. and slug tuned for each
•band - this has no-t'proved to be any disadvantage. At present only 20 and 40 "GE are
covered mth the same oscillator range of from 10490 kc to 10860 kc which gLves neat
coverage of 2,0 mx 'and. ade^ua-te 40 i% Dandspread.
Prior -to the concoc-bion. of -this particular front end -the thought of
an S2 signal vi.rtuall ,y 100^ ( even without power noise ) did not occur, but
thi8"p^r:fcicuiar-dream is now a reality as signals really stand ^out^of a duiet^ackgpoand
also lt-has very adequate s nsitivity. I^ew Town kill - o -_watt^alley proved freedom
from cross'modulation and more than adequate gain. As we doat have the equipment
measure"s/n ratios the performance comparisons are made with tee hack converter^ ^ ^ ^
'RF'/ 6AG5 Mxer, ~12AT7 oscilla-bor ) the oomparison leaves n^ rooni for^ouM^thi
low^i7e3fr'ont 'end"is a'Rolls Royoe and'the conver-ter an Aas-tin 7 among front ends.
The tlon-thly Bulletin of -ttie Wireless . Institu-te of Aus-tralia
December,. 1-6 Tasmanian Division. . -. :. . • I>a <2
"TECHKIC^iL = A HOT LOW HOISE RECEIVER FRONT END by Sreg Johnston ...., continued
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On© point to 7/atoh when go.ttin. g ths 12AT7. to mix is the pjnplitude of. th'e^injec-bion
voltage"-^auch less voltage is required here than for pG n-fcode..
a If th
e^
oscillator
^voltage
is too high all sorts" of spurious responses result ivi-bh near zero outpii-t. Ko real trGuble
should • be encoun-tered with -the RF stege stalility provided -fche centre spigot of ttie valve
aud the Aiold (. pin 9 ) are earthed properly. If this does_not^ do the jo-b then it may
be necessary to'tnser-b a neiitrali sing coil in plaoe of•the 33 olm rosistor between pins
1 and 8, this was not necessary in ay o.wn case.
Sorry to cut you short here Grog but I shall conoliide your fine effort nex-b month. Ed.
73 1-i.n-til nex-b raontli
Ted Beard VK7EB
for Bulletin Cor-imi-ttQG,,