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1970sDocument1978QRM Vol 8

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RADICO PO Box 1010

LAUNCESTON 7250

Bulletin issued by the Northern
Braaches of the Wireless Institute
of Australia, Tasmanian “Yivision.

June 1978
Vol. 8 No. 3

Registered for Posting as a
rublication Category B,

MEETINGS

JUNE S NORTHERN BKANCH - CLUBROOMS - 34 BCURKE ST. 8 F.M.

JUNE 8 NCRTHWEST BRANCH - LAKINS HALL - ULVEKSTONE & P.M.

CONTENTS

FAGE EAGE
QRM CCMMENT 2 DX NCTLS 6/7
GENERAL 2 - RF PROCESSING 7/8

o BUY AND SELL 2 MURFH'S LAk FLUS CTHEKS 9

AOCP CLASS REMINDER 2 NOKTHERM BrANCH NOTES 10

BATTERY CHARGER 2/L ECCNCMICAL 10M BEAN 11

NCRTH.WEST NOTES 5/6 T.V. PAKT III 12
Page 2 Q kM June 1978

QRM COMMENT

Welcome to another issue. I'd like to introduce to you our Sub-
Editor for the NW coast, Joan Fudgs., Joan and her husband, Peter, VK3ZFP/P7 are
nowresident in Tasmania. On behalf of all the members we hope that yourstay will
be a happy one and full of DK. Joan's address is 22 Zlliot Street, West Ulverstone,
7315, Would members please forward to Joan any articles for QRM - they needn't
even be typed, just legible. To get you in the right NW spirit an article by Brian
7ZBC is included in this issue, We really do need items for QRM so pleass extract
the digits!

The RTTY night on 17th May at the Northern Branch Hall went off really
well, with fourteen members and four teletype machines in attendance. Peter
Ackerley from the Central Telegraph office was our guest speaker and in conjunction
with some very sophisticated equipment managed to get a few of the machines on the
corract speed and working properly - many thanks reter.

STOF PRESS STOP PRESS

An evening at the Princess Theatre, Launceston can be arranged for
Friday night, 16th June to ses the film "Saturday Night Fever" starring John
Travolta and Olivia Newton John. Supper will follow at a venue to be arranged;
patrons are asked to bring a plate of goodies. Anyone interested in going please
ring Marg Grant (Launceston 9823u! ) by Tuesday 6th June so that a block booking
may be arranged - minimum number 20.

WANTED TO BUY OR BORROW - Bob, VK7ZRF

Crystals in the range 13,766 = 13,866 or 4.588 = 4.688 Mz

+ bt

"4 LITTLE BIRD TCLD ME"

That somecne in Launceston has been pirating for nine months!

When is Kirby, VK7ZKB going to be heard on HF?

That we might be getting another licensed YL on the NW Coast!

That Lionel Bird is going tc write an article for QRM on the
Convention he attended in Melbourne.

*t o+ttt

REMINDER! A.C.C.P. Classes 1978

June 12: OHMS Law and Resistor Colour Code
June 19: Vacuum Tube Frinciples
June 26: Vacuum Tube Princigles
July 3: Vacuum Tube Principles

+ 4+ + 4+ o+ o+ 4+
June 1978 QRM Page 3

~BATTERY CHARGER =-

If you have a heavy duty transformer which has ahigher secondary
voltage than you would normally desire to make a battery charger
with then this circuit is just what you are looking for.As shown
the circuit is capable of charging a 12 volt battery at up to a
6 amp rate. Other voltages & currents from 6-600 volts & up to
300 amps, can be accomodated by suitable component selection.
When the battery voltage reaches its fully charged level, the
charging SCR shuts off, & a trickle charge as determined by the
value of R4 continues to flow.
CR4 & CR5 deliver full-wave rectified DC to SCR1 in series with
the battery to be charged. With the battery voltage low, SCR1 is
triggered on each half cycle via R1 & €R1. Under these conditions
the pick-off voltage VR at the wiper of potentiometer R3 is less
than the breakdown voltage VZ of zener diode CR2, & SCR2 cannot
trigger.As the battery approaches full charge,its terminal voltage
rises,the magnitude of VR equals VZ (plus gate voltage required to
trigger SCR2), & SCR2 starts to trigger each half gycle. At first
SCR2 triggers at YP/2 radians(90%®) after each half cyclestarts
coincident with peak supply voltage, peak charging current & max-
imum battery voltage. AS the battery voltage climbs yet higher as
charging continues, the triggering angle of SCR2 advances each half
cycle untill eventually SCR2 is triggering before the input sine
wave has sufficient magnitude tD trigger SCR1. With SCR2 on first
in a half cycle, the voltage divider action of R1 & R2 keeps CR1 back
biased, & SCR1 is unable to trigger. Heavy charging then ceases.
Dhode CRJ & resistor R4 may be added,if desired,to trickle charge
the battery during the normal"off" periods. Heavy charging will
recomence automatically when VR deops below VZ & SCR2 stops trig-
gering each cycle.
When setting up this circuit I found it difficult to get the
circuit to regulate down low enough in voltage. The problem was to
get the right value of resistors R¥ & R2 to operate with SCR1.
To overcome this I connected a 1.2K pot across R1 &R2 & adjusted
it to get the required maximum range of operation.
The unit is OK to float a battery with while operating a valve
rig but SCR switching may be heard when operating solid state gear.
73'S VK7ZBL
June 1978

SCRY
GE C20F
OR GE Cinzg CRY g1
12K
L7
6t Alyn
Sw
yn
T Sw
=
210 /|1.6

11
Batreay ()HARGIN e )
AL\— Qﬁsvs‘roks T WATY ExckePT AL NOTED
Page 4

RecuLaTonr ({nrnm_ ac R'I DEPENDENT oAl (.A'rg’j: VALUE
or SR
June 1978 QR M Page 5

SOMERSET JAYCEES HOBBUES EXHIBITICH

On 1Cth/11th June the Somerset Jaycees are holding a hobbies
exhibition. A feature of this will be an idmateur Radio displaey, including
a working station. Anyone who can assist with equipment, displays or help
in any way contact Kirby Cunningham, Shane Fuller or Stephen Russell.

Ft Pt Err o+t

For anyone interested in Cptical Astronomy, t he 22nd June is
their lucky night. The Telecom Society is holding a lecture/discussion in
Burnie at the Marist Regiocnal College at & p.mes = Cost FREE. The lecturer
will be DR, M. D. WATERWORTH, Head of the Optical Astronomy Research Group
at the University of Tasmanis - This should be an interesting and educational
evening.

b b A E P A

NORTHWEST BRANCH nOTES by JIM VK7LO!

rnother well sttended meeting was held in Lakins Hal', Ulverstone,
on Tuesday 9 May when we had an attencance of around *C, Visitors included
Feter Frith VK?PF an4 /lian Irench of .Lynyard. '

Before the meeting commenced, one minute's cilence wec observed
as a mark of res ect with the accidental death of member hay kaxfield of
Ulverstone.

The minutes of the last meeting were read by the Secretary and the
sreasurer's report wae reac by Ivan = VK7LOA/Lli,

Faul Blake, VK743 was elected as Council kep. hRobert Jordan of
king Island was elected ss - member of the ..I.~. John, VK7L has been
elected ag Fatron of the ' l.ns (Tas, Iivy.

Feter, VE7iP gave u most informative talk on such matters as the
frequencice to be submitted at (nkC 1979, and also or the cost involved in
sending our representative to . AxC,

Alse, pgenersl t@picﬁ of rYederal sctivities were discussed anc were
well reeceived, The extra SOhC section which hss been granted - or soon to be
granted = to novices in tne 80M Band met with grest approval,

Tarliamentarian, Mr. nay Croom, will give an informative talk at
next month's meeting e&nd we would like a good roll up.

Max, VK7NX gave some information on the progress of the new
kepeater for the Coast. ihe present one in use, kindly loanecd by the Southern
sranch, has been offered to us at an acceptable vrice. It was agreed at the
meeting to purchase the repeater. lax also gave an informstive telk on
kKepulations, especially regerding 'Third Farty Traffic ard in view of the pointe
ne highlighted, it would ne wise for us zl1 to '"reacd the fine rrint'".
Fage 6 . R M June 1978

(J\

x
30b Croprer, VK7BY went to a lot of trouble in preparing some
very informative charts for his talk on "Speech rrocessing', and gave a very
professicnal lecture. bBob suggested that when cne hears, for instance, the
word "Sat' from a SSB Receiver - you LO NOT in fact hear the first syllable
"S" because of the clipping effect of the filter, Try it sometime.

There was much lively discussion around supper, and it was most
interssting to hear the reports of '"processing' by various members.

Jdim, VK7.(l., apologises for the shortage of "AR" this month, but
would advise thet he has plenty on hand HI!

Jim also =advises of the receipt of an unusual GSL card from Lun
City, Fhoenix, Arizona., This was a packet of "Cactus Candy" made from
several ingredients including the juice of the Frickly Pear (Cactus).

This is just cne interestingfact of AMATEUR RALIC.

This wrape it up for this month.

VY 73
Jim VK70V

+ 4+ + +F + o+ o+

DX NOTES - By COL, vK7LZ
Although some of the goodies mentioned last month didn't eventuate,
I feel sure that the DX gang would not be disappeinted. C31AC and C31FH both
showed up on time from knaorra, ZK2AV and ZK2TT made most VK7's hapry, particul-
arly with their 21 and 28° activity and although the Y1 didn't help us,
more activity is promised from Irag in the future.

The DXpedition by F2GJS and FACYL to Cocas Keeling was postponed
until the 21st May and I hope you have VKQYL and VKSYS in the bag before next
month's notes are read.

A look into the crystel ball ancd we see VK9Zh scheduled for August
from Mellish keef with darry VKZ2BJL in the driver's seat whilst Bill VKOSZM looksa
almost certain to return to (illis Island in June.

ZSY4MG advises that a2 station will be signing HS5RAC from South
Bophathutswana before these notes are in rrirt, this will be & permanent
licence with high power to good antennas.

A large scale expedition to Chathsm Island is scheduled for
cperation from 27th Cctober through to 6th November. Six operators will
participate and operation will be on 3&£B and Ci anc all bands 160 through to
2 metres. OUscar & will 2lso be used - more sbout this later.

£lthough 7HL hasn't beer heard lately, 7BC has picked up a few
new ones, 7CH roused out OESCA/YK on Ci, but missed out on ZDS5SA. 7AE and the
novices have been doing alright with their low power, 7NAB nabbed UBSVAu on 28
mhz for & new country, about the best I could find was HV3SJ in Vatican City.
7DK now has his 50 foot tower up and is mounting the rotator - competition is
sure building upe.
June 1978 ¢ kN Fage 7

Some of the best stations logged here during the month were;
bearing in mind that several others (some of which are still on the secret
list) were logged by other licencees -

28 mhz C21AA, KGHJLL, KPLKK, UA4sSAX, UAGLBC, UWQVA, UBSVAZ, «£:1J,
YIBKY, YU2kQG, 2S2Ek, IsS5BH, ZSWMG/HS, ZK2TT, 7Q7ZE, 9J2GJ.

21 mhz ISeWWL, ZK2AV(Cw), ZK2TT, 4S2Ek, ZS20M, «SUMG, ISUMG/ES,
9J2GJ.

14 mhz C31PH, CNBAK, EA8GL, EASLO, HCSPC, HV3SJ, LX1PS, LX1RC,
LU2HAR, M1D, GM2BMJ, TJ2F, UF6VAG, VO1EJ, UR2QA, VR8O,
VSSMM, ZK2TT, STS5ZK, ©0G1JU, OG1xB, OHIEV.
(SL Information

CN8AK via LABHLP HV35J via WAKhH 9G1KB c¢/0 VE3AEK
A via, WALSSU . o
¥§§§é v}?C.hggx 1825, Kumasi, Ghana.
VKSYS and VKGYL v staticns ¢SL to KG4UTE
all others to F6CYL.
SISZR 3.r.2C2, houakchott, Kepublic of Mauritsnis, «est africa.

ZK2TT sBaruch Sheinberg, 4 Pingas 5t., Tel-aviv, 62007. Israel.
A self-addressed envelope and an IkL will be necessary if you want
a ZK2TT «SL.

+ o+ o+ o+t o+ o+ o+

"RF FROCESSING = GOCD Cx BrDY by JIM VK7WNOW

Much has been said and vritter re the merits - or otherwise of
""Speech rrocessing''. In my opinion, if used correctly, opeech frocessirg
can be of immense value, especially when one is running low power under
adverse conditions.

The better type of processor would arpear to be the true "ki"
speech Frocessor. There are two popular types of xI' irocessors, ore is the
CRYSTAL LATTICE rILT:iK type and the other is the 'FSN' or IHASE SHIFT type -
and of these, the XTiL LATTICE IILITLR type gives the best audio response.

what is the advantage of an ar Speeci. irocessor?

Briefly, it "fills in the holes', or meintzins "'the average
power" of a transmission. It is so good that under ccnditions of heavy
itEXICO, it means the difference between a 'contact' or "no contact'. An
efficient XTAL LATTICL »ILTtR type processor gives an increased "Talk Power™
of around 6 IB.

I have had &SC's under adverse concitions when the operator at
the other end hes said "Your signals are Q° - you are not moving the 'S' reter
but you sound like 55", Under these conditions, with the processor switched
out, the contact would have been lost.
Page & ¢ R M June 1978

A large number of operators 'over drive" the CUTPUT of their
Frocessors. 7Tnis is fatal. Your input level can be checked on your 'LEVEL
METER' but the 'OUTFUT' can be ''wound up'" too far. A reliable, simple
method of checsing the "Processed Cutput' is to patch the “cutput" of the
Frocessor into the 'LINE INPUT' of a good cuality tape recorder - say a "few
words on behalf of the working class" and play it back. You will soon hear
when you have found the correct setting.

I 1ave had many complimentary remarks passed regarding the audio
quality of my ‘ransmission from many countries in the world using two popular
makes of RF Syz2ech rrocessors. Broadcasting stations use them so they can't
be too bad.

Il lustrated is a Block Diagram of a better type Processor. You
will see that .t is virtually a SSB Rig in its own right.

BLock DinerAM
.

%& BALanc o
BALancey CR/STAL
L ) -
'z MODULATOR FICTER
@ L
71/

LocAaL

0CIkhATOR

CRysTAL 4
=0 7015 MuzZ .
(10 + 1265muz) METER
- 3 o

= LEVEL AM P g
LRIMMEL l\’l&TE!{
: 4 5
=

7 5 {
v

77
June 1978 S Page §

>CME LAWS YOU MIGHT NCT HAVE heARD OF}
s ss o D ii T B S so 20 s i s eA B G A RW DG D DS e s LW T S P

MURPHY'S FIRST LAW If anything can go wrong, it will.
MRS, MURPHY'S COMMENT Murphy was an optimist.
MURPHY 'S FOURTH LAW If there is a possibility of several things going wrong, the
one that will cause the most damage will be the one to go wrong.
FRANKLIN'S RULE Blessed is he who expects nothing for he shall not be disappointed.
JONES' LAW The man who can smile when things go wrong has thought of someone he
can blame it on.
THE BUTTERED~-SIDE DOWN LAW Any object will fall so as to do the most damage.
MRS. MURPHY'S COROLLARY You cannot determine beforehand which side of the bread to
butter.

ZYMURGY'S LAW OF EVOLVING SYSTEM DYNAMICS Once you open a can of worms, the only
way to recan them is to use a larger can.
THE HOW COME IT ALL LANDED ON ME LAW Whatever hits the fan will not be evenly
distributed.
GRANDMA'S AXIOM A chicken doesn't stop scratching just because worms are scarce.
MOER'S TRUISM The trouble with most jobs is the resemblance to being in a sled
dog team. No one gets a change of scenerv except the lead dog.
BUNK CARTER'S LAW At any given time there are more important people in the world
than important jobs to contain them,
WILKERSON'S LAW The anatomy of any academic group includes four kinds of bones:
1. wish-bones - go along with any idea -1t want others to do the work;
2. Jjaw-bones - talk a lot but do nothire.
3. knuckle-bones - knock everything everyone else does.
4. back-bones - who do all the work.
PROFESSIONAL RULES FOR DECISION AVOIDANCE
1e When it is not necessary to make a decision, it is necessary not to
make a decision.
2. If you can avoid a decision, do so without delay.
3. If you can get someone else to avoid a decision, don't avoid it yourself.
4. If you can't get one person to avoid the decision, appoint a committee.
DEFINITION OF A COMMITTEE A collection of the unfit chosen from the unwilling by
the incompetent to do the unnecessary.

FANDEL'S RULES FOR ADMINISTRATORS
1. Hide!
2. If they find you, lie.
INHOFF'S LAW The organization of any bureaucracy is like a septic tank
— the REALLY big chunks always rise to the top.
THE GOLDEN RULE Whoever has the gold makes the rules.
fage 10 § June 1978

0
=
LWORTHERN BRANCH NOTRS by MAURICEL, VK7JU

The Branch Meeting was held on 12,/5/1978 at the Bourke Street
Clubrooms. The Fresident, Joe VK7JG welcomed zll members and submitted
applications for membership on behalf of Leslie narper and David Simpson.
A request was received from Mike Hennessy on behalf of w.I.A. Division to
take over the rost Office Box 1010, held by the Northern Branch; the lhorthern
Branch to be rrovided with a new number in lieu and reimbursed accordingly
by Livision. [he request was agreed to subject to satisfactory arrangement
regarding anotier F.U. Box.

Ay oroximately 12 mobile 2 metre stations were made available tfor
WICEN exercise in conjunction with the Australian Equestrisn irials staged
at Relbia by Dhorthern Tasmanian Equestrian Club and the wxaminer Daily
newspaper., Full details to tollow in ~.k.

It was resolved that Bob, VK?7ZRI be granted funds to purchase a
treated pole t> allow antennae to be hoisted at the Bourke Street Clubrooms.

At the conclusion of the General Business, a very interesting
lecture was de .ivered by Lindsay Lowl VK7ZLD, tracing the early history of
telegraph and :elephone pioneering and development from the early 1Z60's up
to the present time in the State of Tasmania. The lecturer alsoc traced early
cable links fo- telegravh and telephone between Tasmania and Victoria before
Federation and after formaticn of the Commonwealth and rounced off with
future developients in regard to optical fibres in the communications field.
Thanks, Lindsa ’.

7% es till next month
Faurice VK7JU

+ + + + F+ o+ + o+

NG T T
NZw \.oh;..us
ee——

Flease let GRM know of new call sign holders so that we can
ensure they geu a copy of <RM.

+ + + + + + + + + +

HEAKD AROUND!

+i h this meter I can measure my own SwAR or by putting it in
reverse I can ftell what sort of SUAR you're putting out - Good Buddy!

Gi-e a count from 1 to 10 so that I canISquelch you in!
+ o+ 4+t + o+ + o+

FROM BILL TANN k ON CLUBRCCM MENAGER

wo 1c¢ members please note that we share with Lifelink all but
our own vworksh p; we do not own the building (unfortunately). Any meeting
envisaged or o her usage can only be satisfactorily arrangec by mutual
discussion bet een the IANE and Lifelink, if you cannot do this, I will.
The earlier yo : book the yplace the more certain your operations will be CK.
June 107&% o RN Fage 11

~s Clubroom Manager, all I want is to know anything that affects
our clubroom or is going on in relation to it. I do not intenc to be obstructive
as my main funciion is to maintair liaison with all concerned and get for members
(if humanely po.sible) their pet achievement or recuirement under way. But,
remencer, I'm nct in the spirit world yet, I cannot read your mind!

+ o+ o+ o+t o+ o+ o+ o+ 4

JUNE_PERSONALIT | VK 7 RH
Rob n Laird Harwood, nickname "rob'', first _icensed in 1971, Lob
is interested i Ch and also likes cooking. hot interestec in short '"Hello",
"Goodbye'" type sos -~ really likes to get to «know tiie man on the other end -
hopes one day t. get an RTTY, Other interests incluce music, reading, theology,
writing. Curre
.t gear is FT 200 transceiver, Mk€'s, FKG7 receiver with 6 and 2
metre convertor .

+ o+ + 4+ ot o+ o+ o+ o+ o+

£ ECONCMICAL 1) METREL BEAM by BRIAN YOUNG, VK3BB5

Aft :r hearing many reports about how good 10 metres is likely to b e
in the next cou:le of years, I made an effort to listen on this band. The onl y
aerial tnst I hid which was anywhere near the frequency was an 11 metre 5/8
ground plane. everal contzcts were had usirg this system but of course it was
far from optimwi.

I a:quired an 11 metre ? element beam and decided to cut It down
for10 metres.Th.s beam had a 12 foot boom so this somewhat determined the maximum
theoretical gaii.

The gamma match was not altered, only adjustec. It came down to
1.3t1 or less aross that part of the band in which I was interested. It was
centered on 28, MHZ. The first 7 contacts were 7 different countries, and I
find that it wo ks really well, There is no weay of determining the gein
-+
because of limi ed facilities. Anyhow, I am pleased with it,
Page 12 ¢ RM June 1978

TELEVISION SYSTEMS - PART III MALCOLM, VK7ZMM

In order to further understand the television system as with
respect to the frequency taken up by a signal it is necessary to understand
the frequency spectrum of a square wave. You may ask WHY a square wave?
tell, a square wave is the most fundamentzl of the '"complex waves". Complex
waves can be considered as being formed by the algebraic sum of a large
number of component sine waves., To construct a square wave it is necessary
to add in the correct phase and with the amplitude all the odd harmonics to
infinity of the fundamental freguency of the square wave., It is only
necessary in theory to sum the harmonics to infinity as in practice the
higher order components become smsll and insignificant in amplitude. To
obtain the desired result 211 the components must begin at zero at the same
time and the amplitudes must be according to the reciprocal of the order of
the harmonic.

Therefore a squere wave consists of:i=

fundamental sine wave
+ third harmonic of a third the amplitude

+ fifth harmonic ef a fifth the amplitude
+ seventh harmonic of 2 seventh the amplitude

+ 4+ 4+ o+ o+

AFCLOGY

I must apologise for the late delivery of GRM - My family were
involved in a car smash and I've been very involved in getting everyone and
everything mobile.
NAC VK7CCC

+ o+ 4+t + 4+ + o+ 4+

ARTICLLS FOR QRM

To date there has been little response to requests for articles.
Cne from the NW area with the remezinder from staff around Launceston Airport -
come on fellas - articles please!
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