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BULLETIN ISSUED BY THE NORTHERY ZONES OF THE
WIRELESS INSTITUTE OF AUSTRALIA TASIANIAN DIVESION
e
SEPTEMBER
VoL, 2 NO, 6
REGISTERED AT G.P,0. HCBART
for transmission by post as
a periodical, CATEGORY B,
VE7IV DE VK7ZNR
Thanks John. I would just like to say that,
Had those whose deaths we were remembering during the R.D, contest been
R.D, contest been "On Air" during the weekend they would have been justly proud
of the Northern Zone participants, It was indeed a friendly contest although at
times the going was hectic was never a rat race, As the day went on operating
proceedures bécame more proficient and any fresh call that dared to call C Q@ Contest
were held until all were satisfied and contacts exchanged, It was these casuals
thet 'added spice, just when things quietened, up popped a new caller and it was
on again, )
Not all was sombre, There were the humerous occasions, such as Col 7LZ
quietly asking who was waiting and then virtually disappearing for a couple of
minutes whilst call signs came back to him like a roll cell, ask a silly question
Coll
The same treatment was extended to Gordon 7GW and Peter 7PD who gallantly
‘but some what foolishly made the error of coming "on air" on VHF during the last
hour of a most memorable contest, It was said that Wally 7ZWX had the most
frustrating time towards the end (when he was not sought after) had a transmitter
‘4;
audio fault muich to the dismay of the hounds,: But I reckon Peter 7PF had the
Qi
harassing time by the groans he made as he listened to the crashing of relays
from his box on the mountain,
My comments so far have concerned the VHF bands but I'm told that the HF¢ers
had their share of glory if John 7JV's score is anything to go by, and according
to numbers exchanged with VHF.ers in HQ zone they too had some action, Finally
our link to the Coast was Ian 7ZIE who was as regular =: the sun.
To those who could not participate through sickress or other cormitments I
commiserate and hope that next year you have better luck, to the XYLs-YLs and har-
monics I say thank you for letting us possibly muck up your weekend,
If Tasmania does not recapture the Trophy back this year it would not have
been the fault of those who '"came back" nor of the 'ncw breed" who have so ably
followed in the footsteps of those departed,
73
7ZNR,
R
K IR K
MEETINGS
Scpt. 5th NORTH WESTLR .ZONE - LAKIN'S HALL, ULVERSTONE
Sept. 8th NORTHERN ZCNE - A,E.B, ROOMS, HIGH ST, ROOM 10 - LECTURE BY
MR, KEN ATHERTON ON SKINDIVING, ALSO KEN WILL SHOW SOME UNDERWATER
COLOUR SLIDES -
miuamfl
Fti e . Y.,R.C,S, CLASSES
Sept. 9th & 23rd KINGS MEADOWS HIGH SCHOOL
ORI R MK
Oct, 7th & 8th - VK -~ ZL CONTEST PHONE
Oct. 14th & 15th - VK - 7L CONTEST C.W,
PECE 2
NORTHERN NQTES,
Once agaifi our meeting was well attended with 32 present, A new face was
Ken Higher,
Business matters went swiftly - only real items were the projected change
in repeater call sign (to VK7RAN) and suggestions for encouraging activity in
the RD centest, Major ifem on the agenda was a diséiay of members! equipment,
It always is a shock to see the variety supplicd., Noted;
(1) John 7JV demonstrated his SSTV using a tape recorded for him by a W station.
(2) A number of commercial wnits were displayed by Norm 7ZVR, A 460MHz pocket
transceiver and a mobile caught our attention, Even had a 75 MHz filter!
(3) 7BC discussed his Heathkit SB101 transceiver,
(4) Mn I.G.L. solid state 2x M wnit was shown by Reg 7KK.
(5) The SSB tucker tin tx rccently described has been keeping Joe 7ZGJ busy
as has his 6 & 2 meter 20 watt solid state mobile
(6) Peter 7PF showed two aircraft radios including an ADF with a frequency
synthesiser
(7) Don't know what Bob 7ZRF does in his sparc tirme but he presented a partly
built vidicon camera, a varactor 144 to 432 MHz tripler, an instant warm
up 10 watt 6 meter valve final, a 2 meter converter (solid 8tate) and a
single IC crystal locked receiver ($4.50 for an RF, IF, Detector, xtal
oscillator and audio!l)
(8) Bill 74K showed the ultimate in a non-frequency sensitive SWR meter/in
line power nmeter,
To cap it off Joe, 72GJ nlaycd tapes of some of his 6 meter scatter contacts,
He must have audio filters for carsi
B RHHRRH KRR KN
If Nerthern VK7 is eny guide, adding the 2-hourly limit for reworking a VHF
station in the R.D. contcst mst be the brain wave of thé century., The en-
thusiasm of 7 calls had to bc heard to be belicved - many of them made up to 150
contacts] Aoparently 26 differcnt call signs were hcard fhrough the Mb, Barrcw
repeater, Quite a few crystals around for a "temporery" frequencyi
BULLETIN OF NORTHERN ZONES W.I.A. TAS SEPTEMBER, 1972
PAGE 3
NORTH WESTERN ZONE NOTES.
Cur annual meeting was quitc a success on ‘lS;t August, Tony 7AX vacated the
chair for the election of President but was very smartly voted back to it for
| anothcr.term. TF customers must be satisficd, _Likem‘se most other officers werc
2lso woted back, In fact the clection was a waste of time, Tony presented his
annual report, disclosing a round of activities for the year, quitc a successful
oney Likewisc our finances proved satisfactory and our couipment store turned
over around $350400; It appecars that there are still amateurs in the arca doing
seme building,
It‘was decided to deter ladies night to 3rd October for possibly better veatk
‘ cr. 0.}, pleasc pass this to the YL or XYL to rcads Ladies, we offer you a warnm
welcome, a talkie picture show, musical items, compctitions, dancing and a man-siz
supper, all dished out by the men, What more could U ask., If you can let us knot
Couples from other zones are welcome but we must be ‘gdvised in advance, After
the meeting we were most intrigucd when Peter 7PF gave a lecture on tracking Oscar
with some most ingenious =pparatus, Also David 7MS gave a thumbnail course on
keeping R.D, céntacts undcer contrel. That's something the computer won't do for
you David,
Sew a TH6DXX Thunderbird lcave this area for the Northem Zone the other day
and I forecast that-somc Johnic up there will socn be punching out a mighty signal
To reiterate our office bearers arcs~ President . Tony 7AX, Vice-Presidents
Kin 7KH and David "MS, Sccretary Mox 7MX, Treasurer Grcham 7ZAR, OSL Officer
Harcld 7MZ, Equinment Store Ian 7ZIE,
he gave me a number, said thanks end followed up with ~"This is my frequency old
man", New, there's a new trick to an old game., By the time I closcd my mouth
it waé toc late to reply. HI,
SEE YOU NEXT MONTH ™MX,
R RN
Twe incredible RD scores were achieved by GREG 7KJ and JOHN 7JV with arcund
600 centacts, CONGRATULATIONS|
PAGE 4
1972 E.R.E.E, AUSTRALIAN FARADAY LECTURE
The Faraday Loctures were commenced in 1924 by the Institution of Electrical
Engineers in the Unitcd Kingdom, The name pays tribute to the memory of Michael
Feradey, the British physicist who in 1831 discovered electromagnetic induction -
the principle on which the whole of the #lectrical technology is founded, Follow-
ing a tradition set by iraday, extensive use is made of visual alds and the simple
cxplanation of complex subjects, The inaugural Forodey Lectdre in Australia was
arranged by the Institution of Radio and Electronics Engineers Australia in 1970,
"TELECOM{UNICATIONS .. THE NERVE SYSTEM OF MODERN SOCIETY" is the title of
the 1972 Austrclian Feoraday Lecture being presented in all capitael cities and a
number of provincial cities by Mr, A, H, Kaye M.V.0., B,Sc. C. Eng., F.I.E.,E,,
F.I.E. (Aust,), F.I.R.E,E, (Aust,) Assistant Director (Enginecring), Australian
Post Office, South Australia,
The lecturc shows that as socicty grows more cormplex, 1t relies on tele-
commnications to support its social, business and devclopment activities, It
dermonstrates how the telegreph, the telephone, radic and television broadcasting
~and a host of other services - many little known .. ncnctrate the lives of cveryonc,
Coinciding with thc anniversary of the completion 100 years ago of the 2,000
nile overland telegraph linc betwecen Adclaide end Darwin, the lecture touches on
this achicvement and traces the developments through the years, with cmphasis cn
the techniques of today, the pattern, the depth and a glimpsc into the future.
It shows how thousands of sirmltancous telephone conversations can be trans-
mitted over one pair of wircs. Hew facsikmile information, television programncs,
corputer information, a birthday grecting and bundles of telephonc calls can bc
pushed along a virtually hollow tubc and how a houscholdcr cen dial across the
continent as casily as across his own town. The lecture points ocut that the
fustralisn telecormmunications network is part of a werlwide networl,
The rccurring theme is man's increasing nced for ccrrmunication - the more
prosperous a nation becomes, the more telecornmumnications services it requires
and it draws at* 2tion to the intcrdependance of national development and telc-
cortunications development, Finally it highlights the necessity for adequate
resourccs - including thc important factor of humen resources in the scientific
end technological fields - ® mecet the challenges of the future.
eI NI IHIHK KK
The members of the W.I.A. have becen invited to attend this lecturec;to assist in
planning would you please rcturn the slip below bofore Sontember 16th - TICKETS
ARE FREE,
B8 000008 00600090000 000800000080 0°00000 00000000000 00000080000009es09 8800000000000 06008600e00e00@80eso
TICKET APPLICATION FORM
T WOULD LIKE TO ATTEND THE FARADAY LECTURE ON OCTOBLR 1€th, 8pm AVD WOULD LIKE
TO RESERVE ,.vvvveeeessse TTCKET(S)
F NAME
MY £ IS 80606 70585570060
- I + 00005n0086 02 6 ens 05 .
060000000680 o008 3 CALL 000650055500 0000 °
£ADDRESS ©0 00000 °"80000005°-50 . 0000060070000 00860500¢75000500600°00000066000000006000000GOc
0
PHONE
- "ddoooococoeceeo0000e0000006
00
IF MORE THAN ONE (1) TICKET IS REQUESTED PLEASE GIVE N AMES,
BULLETIN OF NORTHERN ZONES W,I.A. TAS, SEPTEMBER, 1972
PAGE 5
SPECITICATIONS FOR SATELLITE ACC By G, Long Chairmen - Project Australis Group
While in the construction stage this satellite will be kncwn as AOC. TUnon
launch this title will change to AO6,
SPECIFICATIONS:..
(2) ORBIT DETAILS: Pcriod 10% minutes inclination 99° to the equator (retro-
grade) hcight 1100KM circular, Midday crossing (local solar time)
(b) Approximate launch date - November 1972,
(e) Ecuipment carried unon catellite:
(a) 1 only lincar translator:-
Input ~ 145,950z ! 50ihz
Qutput « 20,50 YhzT 50Khz
Receiver sensitivity = — 120 dbm, for first detectable signal.
Transmitter ~ maximum output 2 watts peak-envelope - nower,
Modes of translation, A1 A3 A 34
C. W, LM, 8SB.
F3
FM, F.S. I, SSTV
RTTY :
Mso a cs, beacon fregucncy - unon 20,450 lMhgz
(b) 70cm Beacon Tronsmitter:-
Frequency - 435,100Mhz
Power - 0,75 watts
Modulation . 41 (cw)
Information - Telementry, cw — 20 wrds per minute, or 13 words/minute
grovnd commend sclecticn,
- Bodestore rodulation; 13 words/minute,
(c; Telemetry — 24 channels, to ronitor cssential functions,
Codecstore - 1024 bits, of information, A1 mode, ground programmeblc,
will be loaded with crbital or eny other pertinent information for
replay during any orbit).
(c¢) Cormand - 21 commend channels te contrel ell housekecping and centrel
functions aboard the spacecraft, Controcl frequency - within the 2m
band, The commands will be B - (F3), * 7,5 Khz deviation, Required
signal level at ground level expected to cormand satellite: - 2KW
ERP, M1 commends will be in the form of digital code, Because of
the possibility of tampering with commands, All code information
is confidential but may be obtained from the Prcject Chairman under
specific special conditions (i,e, for the specific information or use
by government instrumentalitics P.1M,G, - CSIRC -~ Dept's of Supply
or Defencc),
(f) On_board power supply: Nickel Cadmium battcrics, charged by on~bcard
solar cclls mounted on four pancls on outside of satellite, average
available power 4 watts, at 28 wolts,
(g) Lifetime: Satellite design lifetime is onc year, 21l corponents
manufactured to military specificaticns, As much of the beacon
transfri tter and the cormand decoder (cnly items built in Australia)
as possible are construéted using Australian manufactured and suitable
corponents,
Command Stations in the fustralasian regionse
New Zealand - Bruce Rowlings ZLIWB
Aust, Melbcurnc — P, Harmer VK3ZPI
G. N, Long VE3YDB
West Australia — Don Groham VK6HK
Q. Ro }liu
BULLETIN OF NORTHERN ZONES W,I.A, TAS, SEPTEMBER, 1972
PAGE 6
R’ CARPHONE
INSTABILITY IN 455 IF STRIP,
1a To stop instability, increase capacity of deccunling electrelitic on
DET i/c awm1306 Pin 7, frem 1 uf to 30 uf.
2. Reduce coupling capacitor from Pin 8 to coil frem.01 to 470 PF ceraric,
INSTABILITY IN FRONT END,
Te Make up a screcr fron tin plate, abeut 1" high and place on the P,C.B, as
shewn in diagram, The scrccn can be casily fixed by drilling 3 heles in
the P,C.B. and using 60A fusc wire as suppcrts,
VCLTAGE ON 455KHz I,F,
The voltage should be adjustcd for maximum audic cut put,
Te When the receiver is roushly alined rerove the zener diode and inscrt a
2K ohn Pot in placc of the decoupling resistcr (470 ohm).
2. Adjust vcltage for maxirmum ncise cutput, it will be found that the cutput
will follow the curve below.
Max ouTRuT
e
c
3 vs N
)Y e
A ee o
: //WM.-_-..———-—
v —_— L T
° 4 S § g vBionid
Maxirum cutput will be between 7-10 wolts, in my case 7.6 wwlts, So a 7.5 zcner
and 470 chn resistor was used, .
3. After fitting a zoncr dicde which will give the correcct weltage, meke surc
the. veltage across the zencr remains constant with normal veltage variations
to the wnit, (11-14 v 1lts)
TO REDUCE AM NQOISE,
After 2ligning receiver uding a F.M, signeal gencratcr switch gencrater te Al
rodulationsand increasc generator cutput, Adjust the 3 455KHz I,F. trensforrers
fer rminimum audio cutput,
BULLETIN COF*NORTHERN ZONES W,I.A. TAS SEPTEMBER, 1972
PAGE 7
oL
ELIVINATING ALLTEENATCR AD GENIERATOR NCISE,
RelAy
vy LOWey LF Hops Tx
o-o
n FF
— Rx
cHoxé - Ferris N2 834
/
/Z_Q_ DC Resisranes —
-
ABOLUT /" SQuARE
25 WATT wmir = = RELAY
/z(\gi———-_—
—-—./
ON—- OFF fx
12V o, ° -—7\
Rx
TO REDUCE DISTORTION IN THE MICIOPHCNE PRI AMP,
Reduce the 33K chn resister from the hase of the 23565 transister to 4 rail
tc 27K ohn.,
R, F, FEEDBACK,
1e Dc not usc transisters with metal cases (TT3565) in the mic pre-amp,
2, The mic gein contrel (TR1) should not be turned full on, maxirun sctting
is about 3/4 on.
IO_STOP SATURATION COIf STRONG SIGNALS,
Placc a DAQO or similar dicde acress L1, cathede to pirn 9,
IC REDUCE AUDIC O.2,
FRoM DTS
27K
1ok Volume
Ik Auvio |
Tc increasc the R.F, Output of thc 25 watt final reploce cne of the 33PF capacite
frem L2 to carth with a suiteble trirmmer with the same capacity and adjust to
maxirunm output,
For morc inforrmaticn centoet VK77GI,