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BULLETIN ISSUED BY THE NORTHERN P.0.BOX 1010
ZONES OF THE WIRELESS INSTITUTE LAUNCES TON
OF AUSTRALIA TAS. DIVISION TAS 7250
FEERUARY
VOL., 2 No.11
REGISTERED AT G.P.O. HOBART
for transmission by post as
a periodical. CATEGOKRY B. PRICE 10¢
EDITORIAL
By the time you receive this you will no doubt have been
informed by the Ww.I.A.bulletin that you have a choice of
councillors again this year.
But more important you will be asked to cast your vote in
favour of one of the two motions which will be presented
at the annual general meeting this year.
Both call for a change in the constitution to allow three
branches to be formed in Tasmania,but that is were the
similarity ends.
One proposal asks that you agree te one of thec branchcs being
Head Quarters,whiech is ofcourse the system that we have
had in this State for some 50 years.
The other idea is that Council be the governing body with
the three branches having equal status within that framework
therefore giving every member in the State a chance to
attend his nearest branch meeting and his veice will be as
strong as that of any other member. &
Please attend the annual general meeting and exercise yéur right
to vote on these proposals.
JOHN VKT7JV
WA K KKK KKK
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MEETINGS
April 3rd NORTH WESTERN ZONE,LAKIN'S HALL,ULVERSTONE
March 9TH NORTHEN ZONE,8 HIGH ST , A.E.B. Rooms
slides of ANTARCTICAby COL VK@JIV/VKTKW
March 17th W.I.A. ANNUAL GENERAL MEETIKG AND DINNER AT
THE GATEWAY MOTOR INN,FENTON ST,DEVONPORT
YRCS CLASSES
-
lMarch 10& 23RD 10 am KINGS MEADOWS HIGH SCHOOL ROOM 38
KW WA IR H KN KKK KR
April 20TH W.I.A. FEDERAL CONVENTION , LAUNCESTON.
W W WK KW NN KR REH KRR RRK R
Qo Rc Mo
BULLETLIN OF NORTHERN ZONES W.I.A. TAS March 1973
page 2
NORTHERN BOTES
A few things going on at the moment for you to keep in mind,
The Zone's Annual Meeting has been postponed to April. Start
thinking about the most smitable persons to fill the available
positions,
A bulk order for crystals has been forwarded to the VK3
Division. When the crystals ordered are received the repeater
frequency will be altered to be in line with VK3's ideas,
Subscriptions to "Ham Radio" and "VHF Communication'
have been purchased by the Zone. It is intended to circulate
these as rapidly and efficiently as possible.
W.I.A, National Easter Convention will be held in
Launceston this year. We will be calling on assistance from
members in various ways- please try to arrange your Easter
holidays with this in view.
Be sure to atténd the March meeting. 'Tiny Tim' Col Perger
VK7KW ex VKQJV will fill us in, via his slides, with his
activities during the last 12 months at Casey Bace.
ot
a o
B oo
3 ats
b
Help make the Northern Zone's Raffle a successt:
How many books have YPU sold ?
If you've run out get some more from Stavo, 7JV.
We only have to the 6th April to sell out.
sl
¥ 32s at-
o s
F
ZQNE FEES
Northern members please note that Zone fees are
now due. Remember that the Zone provides many of the
facilities available to Hobart members and ‘t does this
through your dollar subscription.
YEARLY SUBSCRIPTION ¢4 all grades
Tear off and forward to W.1l.,A. Tas., Northern Zone,
PO Box 1010,
Launceston 7250
NAW OO'OT‘ODOOOOODOOOOUOOOLOOGOOQCCAIJI‘ © 0 000 00 > 0 0 ©
ADDR-E‘SS © 0 0@ 0 ©0C 0600 00 ©0 0 @ © 00 000 o6 002 0002 00 0
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Qs R- M.
BULLETIN -OF NORZONhs
THE W.l.A..TAS.
RN . March 1973
page 3
NORTH WESTERN ZONE,_NGTES
Allattention is now focussed on the Jubilee Dinner to. be
"held at the Gateway Mctor Iaon, Devanport,-en the 17 th March-
not forgettlng the Annual meeting, L you have-not.registered --
__please do so without delaj.
Our Februery mociilog was‘*” L atrtended and a.great deal
.of business dealt with inciudingthe Pori Sorell Hamfest on
25 th February.-By this time .ycu will know. what has happened...
Two-metl:. activity appearn tr have eacsed Qff somewhat’
but there is sti .l plenty, Tony 7AX has converted his new
automobile into a mini nowa:h;a:ea To zce the control, panel is
really something and it really wrrks. _ o
Teny journgy~d - the Stan Wing Mem-riel Lookout.at
Presten -For the Jghn Vo*ie Fielid Day Contest and could be
heard working mainlendcrs. ou & metres. Hercld 7MZ was heard
from the site at one stag” and assisted with the installation
- of antennas.
A welccme visitor during the month was John, ex 7JF,
‘now 3CDX, John looked cver the cld haunts and a very plsasant
evening was gpent wivh some of the local Hhoys.
Ian 7ZIF% hes so*"tled into th~ new QTH at East
Devenport dand so East has now % hems. 1L can no lomger claim.-~
to be the "Vcoice oi’ Bact Devonport® since the-.aliens moved in.
Hi.
s~ LArhel YAV wagz heand working portable in Devenport
- recently.
VHE n aye hveen since Christmas .
‘Had the—pleasuf@of some troual fishing with Harvay.
22YZ,.We wers s . Lhzt we forgot. to talk radio.
CCU nsxt meunth 0 7MX
5% % % 5
Port Sorell Event
" This was a resounding success once again. Thanks to the
organisers.for their efforts,
rough count showed 30 amateurs
(-total about 70) in
attendance. Proneedings were rather late in starting so
not many cf-the-scheduled evenis toock-place,
To control feelings a. little more.next year perhaps
the ruléds-of the crickel matc could be examined. Perkaps
equal batting-time could be given. A resounding win to the
NorthernZone with some hilarious cxhibitions from some. players..
Qe Ro Mo
BULLETIN OF THE IIORTHEN ZONES WIA TAS. March 73
page L
,
-.IETY,T, Ir’;'\r
It is with regres vhat we record the passing of
LON JEISEN VE7IJ on February 24th.
ION has heen o tireless worker for the V.Yt.fi. for many
years aond is well known to all members through his
recent articles in the W.l.A. bulletin
Seems likeeverycae is now using IGL transceivers
on 2 metres, latest crders are from Don VK7DB,
Gordon VK/GW and Peter VK7PD
While on 2 mctres, Jn: 72GJ and BOB 'ZhT have been
working cn the COHSLPQGBl>n of the handheld FM transcelver
as described in the December issue of BREAK IN printed
circuit boards for this unit have been photo etched
by Lon 7700 and arc avallable from him at $1.40 for
€3
the two hcards. LON's address is 215 Carella st Howrah
Peter 7PF isc ncw using ssb on 2 metres for OSCAR
and findés contacts coming ruch easier,
Trevor 7TB may not have been heard on air much lately
but thosce days are ¥ast closing to an end as the fully
golid atate tranceiver he has been home brewing
iz 28 good as i I had the privilege of
hes Ping brth the anc. the transmitter at work
andit sounded :aaLgoou. TREVOR has supplied me with
the complete ecircuil for this wnit, we'll try and .
ransfer it 50 o slenclil and put it in QRM for you.
Its 0no wonder l\r'n keeps ruaning out of equipment,
2L houws after taking recelpt of 50 neosid formers
he had +o send of .flULhC: crder, this time for 100
of them.
Our aspo“J:fi: nembers haviEn®t bsen idle either, there's
been a lci of aitndying going on and Greame Reaedon,
Allen Dw**s ond Peuor Felthem toolz the AOCP exam a
couple of weeks ago and all seenm pretty confident,
Good Luck felliows,
I don't kmow how thay dc it, 1 am referring to the
businesgs houscs of the U.S.A. and England, they
seem to be able ©n Lil1l your order and have it in
your shack witiiin 10 1ay o
Being a loyal citizen L ordered my gear from Melbourne,
I sent the moncy with the order last November and
still haven't got the goods.
Andnow you know why we haven't any printed circuit
toarl in svock.
Whieh makes you wonde» why +the Australian firms
are protected too much.
% % 9
SUPPORT THE TEOPLE THAT SUPPORT YOU
Athol Lawes Ilectrics, Phillips-Astor Industries and
Ron Carter Caltex fervice Station in Kings Meadows have
helped with printing costs and prizes for our raffle-
so next time you need somelthing why not see if they
can supply it first.
QsReMe
BULLETIN OF THE NORTH&RN ZONES WIA TAS March 1973
page 5
TECHNICAL ARTICLES OF INTEREST by 7PF :
Break In, December 2 Mx Hand Portable
An interesting small .6 watt, 6 channel
FM hand portable. This is from the Wellington VHF Group
and a kit is available in NZ for $55 as against $100 for
a larger set in 'Electronics Aust'.
The TX uses a 2N3866, the Rx is single conversion
with 4 10.7 MHz transformers as a filter.
Specificatihons
X 8-10 kHz deviation .6W output
power drain 110 ma, 12 volt
Rx «H uv 20 dB quietmmng
acceptance + 15 kHz
audio output 50 mW in a common
mike/ rocking armature earpiece
Sige Z%H x 2%n x 8"
Weight 20 oz
Information Wellington VHF Group
PO Box 6243
Wellington, New Zealand
Since showing this information at the Feb Zone meeting
a number of units are under way and much intersst has
been shown,
Freguency Syhthesizer for 2 metre FM
"73% QOct & Nov 1972
This 1s the remainder of the article
reviewed in QRM for December and gives circuits and layout
The author had trouble with VCO microphones while mobile
when the oscillator was on the common circuit board. I
believe the real trouble is in trying to go in 5 kHz steps;
the whole design of the control loop and noise reduction
is simplified by ten by using 50 kHz steps. Not with-
standing the design differences there are some useful
idegs to be gleaned,
Power Lead Filter for 432 MHz
73 Oct 72
The author tests various means of de-
coupling power leads at 432 and arrives at an RFC with
two bypass condensers each end; this gives about 50 dB loss.
An RTTY Selcal with TTL Logic
1!73n Nov 72
This intersests me as a means of decesding
the RTTY telemetry for AO7. Each letter is fed into a
shift register and compared with a character store and,
in my case, the required telemetry group would be seleccted
and the remaining value read out on a nixie tube, that is,
when I get a RTTY demodulator built.
Qs Re M,
BUTLLETTIN OF THT™ NORTHERN ZONES WIA TAS March 73
page ¢
TECHNICALARTIGIESOFINTERIST cont
“Regiprocating Detector
"Ham Radio'! March & Nov 1972
" The Aust, EEB" June & August 1972
Th:. detector derives its name by the action
of pulsating sidebands of a signal being converted to
the circular motion of a continuous carrier. The best
description, by the inventor, is in LEB amd practical uses
in a modified recgiver in Ham Radio for March and a WWV
5 MHz TRF receiver in November.
Basically tane detector is a product detector
without a BFO the carrier being generated by a regenerative
action with a narrcw pass band; you could say that the sig
signal introduces a ringing action. The synthes&zed carrier
amplitude varies wiith tne average signal; this is the
whole secret of the derived benzfits. The detedtor can be
used on all mudes except FM., On AM selective fading is
much reduced and on all v’ +ls impulse nolise 1s rejected
because the narrow band filter stops the reference level
increasing at a raie Lo match the impulse noise
pulse so causing clipping. On CW the usual BFO introduced
noise is reduced because the injected signal just matches
the sigral,
LOW POWERDX
G6XW avperently has been busy since retirement
In Radic Communications November 72 he describes aerial
gsite tests with 1 wett apsech elipped ssb. He describes
the use of sloring ground as an aid to boost signals
in the required dircction and he says that as VK7LM
on ths nortkh eoast o Tassie, ueing drift wood lashed
together as a support for a 14 Mhz inverted V on a steep
slope ending in a ~1iif 150 £t above the sea, he worked
OHYURF , LABKG and cther HKuropean stations.
IN HAM RADIO for Nov., and Dec. 72 he describes the
benefits ancd design considerations and some circuits
that he has usced. Geing by his report the apperent
inerease in signal of 8 to 13 Db by RF clippers is well
worth while 1f correctly done.
SATELLITECOMMUNIGATIONS
In HAM RADIGC Nove 72 Some hroad requirements for
communication is set out and in DEC. an article on
polarization of satellite signals using the ATSI satellite
I actually heard scme »f the tests from Hawaii,
To get a true circular polarised aerial system seems
to be harder ithan at first appears, shown 1is the comparison
of average gain of different arrays, a four element beam
rotated for correct polarisaticn had a very good average
.and at times outperformed an 80 element crossed yagi.
I will try to have some more for you next Month
73 Peter VK7PF
Q . R. Mo,
BULLETIN OF THE NORTHERN ZONES OF WI4 TAS March 73
page 7
CRYSTAL CHECKER
Being faced with the problem of measuring the
difference in frequency between a large number of
ecrystals , nominally of the same frequency, in order to
construct a crystal filter, I used the following circuit.
o + /12
¢
2201
Bc /08
BF 115
OR S/"’/l[./'?/{.
100 PF
The output’will be the audio difference in
frequency between the two crystals and can be used in a
CRO or frequency counter or via an audio amp.
It also should be wuseful for grinding crystals
to the same frequencye.
Malcolm. VK7 ZMS
NOMINATION FOR OFFICE BEARERS, NORTHERN ZONE
Nominations are called for the positions of
President )
Vice Presidents Bulletin Editor
Secretary
Treasurer
Nominations should be in the hands of the secretary
by 13 th April. :
I hereby nominate esccssveccaoonensaoses O the
position of
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