QRM
Recognised text
Text below was produced by optical character recognition and may contain errors. Check it against the original.
K
-
)-
s BULLATIN ISSUED BY THiS NORTHERN
BHANCH.ES OF THIE WIKGLESS -INSTITUTE
P.0O. BOX 1010
LAUNCESTON
-
OF AUSTRALIA, TAS. DIVICION. TAS. 7250,
July 1975
B
VOL. 5 No4
L RECISTIERED AT GPO HOBART
for transmission by post PRICE 40c
L
as a periodical. CATEGORY B.
1L
MEETINGS
July 8th North West Branch Lakins Hall Ulverstone O8pm.
1
July 11th Northern Branch Civil Defense Rooms
Bourke Street Opm.
- Followed by Films.
1 July 12th
YeReCeSe
’
MEBTINGS
¢
1
& Kings Meadows High School 10am.
July 2eth
July 12th
& Lakins Hall Ulverstone 2pme.
July 26th
CONTENTS
July 12th-13th ARRL Open CD CW
July 19th=20th ARRL Open CD Phone
July 26th=-28th Country Hunters OCW
August 9th-10th Buropean DX CW
August 15th-16th R.D Contest
i e
July 1975 QR Page 2
Office Bearers for !lort! West 3ranch for 1975.
President: Tan Ellings VK7ZIE
Vice Presidents: lax Ives 2x
Brian Lorl VK743L
Graham Rand VK72ZAQ
Treasurer: Ilax Tves VETEX
Secretary: Groham land VRTIX
Activities Comittee: Ian Ellinss VX721
Bob Simpson VET7ZJS
5. edford VKTSF
Y.R.C.S Co=ordinator: ' Graham Rand VK7z4iQ
Broadcast (o-ordinator: Tony Bedelpr VK73X
Branch Correspondents . Crahem Rand VKT72AQ
Equipment Officers: Adrian Sheriff VITZAT
WICEN Go-ordinators: Bob Simpson VK7ZJS
Q.S.L. Officer: Yoowott Fgpold Yancock VETEZ
Beacon Committee: ' Wayne Gibson
Ian Bllings
Adrian Sheriff
Graham Rand
C" G2 OF ECUITMENT STOVE OXFICER FOR
NORTHERI BRALCH
DUE TO KLVIN VK7ZAH PAVIN™ ULDERTAKTL A "JIZLVE I'OLTH
CcOURLT AD RECUIRING TIME 7O “STUDY, ™E TrUIPIELT CTORE T'AS
BUTEN TAKEN OVER BY DAKKY APTED,
M ST.
65 BROU™H:
5RBEST LAULCTESTON
PHONE: 316643
Nanny will be moving shortly, his’ fiew adrccs will be notified
as soon as the shift occurs so listen to the W.I... broadcast
weekly.
July 1975 GeR.I. Page 3
Northern Branch Notes
The June mceting of the W.I..4. Northern brench was held on
Friday 13th at the Bourke St Civil Defence rooms. The meeting
opened at 8.15 p.m. with visitors 72ZIE, 724T and TZAQ from
the north west in attendance, dlsoc present were Stuart Beveridge
(2 new member) and lir Finlay McClean.,
The treésurers report showed a bank balance of $2035-42 with
the sales for the month emounting to $1427-51 and accounts to
$1287=15 == quite a business!
A specizl vote of thanks to all those who helped 7NR and 7KK
with the exhibition at the Library and specially to those who
T
helped man the exhibition.
Robin T7RH hns asked that any persons with ideas for a VK7 Cvw
net get in contact with him. OCW closses are being heldl at
YRCS meetings in preperation for Novice licencing.
The proposed extensions to the Civil Defence rooms were
|
digscussed and Ed THE reports th it we may have concrete pronosals
-
on which to vote at the next meeting. The proposed bye-laws
were discussed and passed by the mecting in 43 minutes (a recorad
surely). : :
The business was dispersed with by 9.15 p.m. and 2 most
interesting lecture on "The Strange Story of False Teeth™ was
given by lMr Finlay McCleuan - (who wants to sell their teeth
for 2 guineas?). What interesting lecture will wally 72ZwX
think up next?
The repeater has been turning itself off again lately and it
would be appreciatel if members coull let 7PF (or TZRF or 72BY)
know if they finl it off so it can be turned on again with
minimum delaye.
73's Gracme VK7ZGG.
T0 _ALL NORTHERN BRANCH MEMBERS
So that the Northern Branch Executive can better provide
for the social side of the Branch, it needs to know the feelings
of the members on this matter.
Below are a few suggestions on what coull be organisecd.
Plcase indicate your preference by numbering the indicated
choices:
1) Cabaret, to possibly co-incile with & suitable artist.
2) Film evening.
3) 4ll family involvement outing - c.g. trip to Ross Deer Park,
4) Members to mcoke their own entertuinment.
5) Precscent social sile of Branch activities suitables
€) Own ChOiCEreeseassvecacssessscsessnrsssncsscscvacsccnnanse
When completed, please pass your views on to E1 Hewens
VKTHE, either person:illy, or by posting to Ed P,O. Box 1010,
Launceston. If you prefer, bring it zlong to thec next meeting.
73, Brian VKT7ZBY
July 1975 Q.R.M. Page 4
North west Branch Notese.
Our last mceting was our £nnuazl General Meeting and as a result
we hove a new set of officers. Ian 7ZIE is now President yours
truly is secretary and Max is our ncw Treasurer. (I knew Max
couldn't stay out of the exccutive for long).
There has been a lot of liscussion arounl the Branch about the
propose? $4.00 czll on members to be made by Feleral. In general
members are not too hostile about the $4.00 but are worried
about thce possibility of even larger future calls being made
and want to know the cause of the Institute being in this financi-1
mess. ©Somc members had strong feelings on the matter but alas
these were not strong enough to prompt =2 trip to the Special
General Mceting in Launceston. If you ttink this is a dig
fellas you arce dead right. Thanksto those who 2id turn upe.
On to the upcoming mecetingsee«sdt the next meeting a technical
talk will be given on the theory andl przctic:il application of
'‘operational amplifiers'. ©So all you members who are a bit
rusty on the subject let us sce you therec. The mecting after
that (4iugust) we arc having o 'Junk Night', so dig omt your“..:
'Junkus Misclani' and bring it along. A small percentage of
course will go to the branch coffers. ©So lets have a good
role up. Remember, the Branch is under new management and is
rearing to go. Seec you at Lakins Hall.
73's VKT7Z4Q
Jllly 1275- QQROM. Page 5
LADIES PAGE
.r‘\_\"//\
-~ USE BUTTONS FOR <
} (:) prEs (%)
To all you sewing fansvwho like fun things.
Hi Girls, ;
N this isn't a picture of anyone we know,
wlthough some of us may know someone it's like. 4
| Vo, actually this is Ferdinand theFloppy Fro%.
\I borrowed him from Moira, 7GW Gordon's
vNife. He can be made from any material
just as long as they aren't too stiff. Y
= ' )Sew him up end fill him with bird seed.
) Don't use too much seed though because
/ e won't flope I think that he can be a
— /fascinating little creature, and is ideal
/for children of all ages (including adults)\
/ Little Freddy has been known to
.be
B // used for all sorts of things, including a door— |
S
stop, but mainly as a toy for a kiddy. \
I Make sure you give him a good seam /
\allowance, because he may burst with usc. In this
. ‘ day and age is it any wonder.
\ Have fun withhim.
3 73's /
TNR's XYB i et
ANN. |
e
I
!
Cut along unbrcken line.
liachine along dotted line,
— o
JULY 1975 QRIT Page ¢
NORTH WESTBRAICH — TASLANIAN DIVISION.
A
YIRELESS INSTITUTL OF AUSTRALI
ANNUAL PRESIDENT'S RIPORT _1974/75.
It does indeed give me much pleasure to report on the
Branch's activities for the last ten months. For those
persons unaware, members. of this branch resolved to shorten
this and next year to allcw our next year ending to coincide
with other branches and Divisional 4Annual General lleetings i.e.
approximately larch-April.
HA'. FEST.
The 1st. big challenge to the Branch was the organising
of the state Ham Fest: at Turners Be ch. Despite pictures
of Zloom and statements of '*This Branch could never organise
such a function,;™ we took on the task. Those who attended
the function, know the outcome. For those who didn't I can
report from comments receivsd, it was a tremendous success.
Apparently as far as we know th'.s is the 1st or maybe 2nd
time a Divisional *HAVEFIST® w's held on the North West Coast.
Most pleaisinz to me personally, was the offering of some mem—
bers of their services to form a lamfest Com ittee. Also
other persons offering to help out on the occasion. This in
my opinion, strengthened our branch and if all members main-
tain this attltude, it can only les:d to a vetter and stron~er
branch.
EQUIPMENT STORI.
Barly in the year a large quantity of corponents was
purchased privately by a member and offered for sale to
branch members. This hisshlishted the needs to perhaps re-
opren an’equipment store. Grahame Rand VK7ZA) offered his
services am equinment store officer and was duly <iven the
job. Thanks again Grahame.
NyMEMBIRS.
Three (3) ™A™ grade and five (5) 'B" grade members
joined the Branch durings the term, with the »ossibility of
two additional 'B' grade members earlv in the future. A %
increase of this order, if continued, would of course
increase the size of our Branch. T’anks to those members who
made this possible.
NOTICE OF VEATINGS.
As an experlment I decided to personally contact each
member prior to one of our Zeneral lMe~tines, informing them
of the date and other incidentals, activities etc. The
meeting had a record attendance of 38 persons. Althouch the
attraction was perhaps a lecture nd demonstration on Colour
Television plus a guantitv of cheap components for sale, Iim
of the opinion the communicating to various members resulted
in the high attendance. I the“e,ore sugrest the Branch in
future investigates the forv irding of meeting notices to
members prior to meeting.
July 1975 Q.R.M. pase 7
ACTIVITI
IS
on Air Tguipment has be n made availab le at some of
the meetings. This serms to have some attraction especially
to the vounger persons. Also Morse Practice sessions made
available were ponrrly received. I think it would be advan-
tageous to persevere with both of the abowe activities.
MINI "HAMFEST™
The normal "IMini" hamfest at Port Sorrell was azain held
in conjunction with the Northern Branch. I'm sorry to report
it was poorly attended bv N/West Branch members. Despite
this, the Northern Branch made .up for the lack of N/West
veople and a sreat time was had by all.
QIVI.S_IOZt%II ‘A- "_T_:"II & DI1'
llL °
Little to report as far as this Branch is concerned,
except agzain, very poorly atiended by our members.
BRA
BRATICH CORRHESPCNDENT
T Unfortunatliey-our Brancl;Correspondent resigned due to
personal reasons. A volunteer in Regzinald Carter tock the jobe.
DIVISIONAL BROADCASTS.
This Branch has had a very successful vear regarding
brnadcasts. I'm pleased to reort we have the highest
participation ofH.F. originating stations i.e. four (4)
located from Devonport to Burnie. <hank you to all gentlemen
concerned for doing this thankless task. However there are
8till plenty of wacancies for V.H.F. relay stations. I would
like to se2 some more interest shown in this area.
BIVISIONAL COUNCILLOR.
Consratulations to Grahame Rand on being elected as a
Divisional Councillor again this year.
I'OR5E PRACTICE 33535I0NS.
Max Ives VK7IX has offercd to conduct MMorse Practice
sessions on the V.H.F. Nets. for those interested.
VVGI.C.._I.I\TQ
The Branch resolved to become involved again with %.I.C.E.DN.
Robert Simpson VK72ZJS offered his services as Branch
co-ordinator.
YoRoeC oD
T The most important activitv in my vie', was the formation
of a Radio Instructional Class held at Lakin's Hall Ulverstone
each Saturdayv Fortnisght. The class has now come under the
Vouth Radio Club Scheme. The class is beins conducted under
the guidance of Grahame Rand VK77A3 with other helpers in-
cluding Adrian Sherriff VK7ZAT, Ian BEllings VK7ZIZ and Wayne
Gibson. Average attendance is 12 plus, which is very satis-
fying, considering the class has only been operational since
February.
CONCLUSION
fbove are some of the main activities which come to mdnd.
There are others of course. I trust ALL members in the forth-
coming year will assist your incomein office bearers to ensure
another successful year.
Finally, thanks to all Office Bearers during this current
term for their assistance.
A.I. Bedelph.
July 1975 » .'.",'.-,;.._.’\ edoggle’ 3 QT 0 : . T‘age 8
¥TF Motes by Prank VII7TRC
Conditions have been averge for the sezson an? times
spent listenineg with the strongest paths from this NTW
being mostly North/south between 0300/100007™,
3RCOL who is operating from Todrigves between 13th June
end 13th July has not yet been he:rd from here, some V173
stetions sre looking for him Gaily and hig overating times
should be knovn in due course.
The 'KOAA expedition fto Serrons NBank in the Caribbean
sea wss heard with weak signels on 38R and € between 0400/
06006"T on 40metres/20metres on 20/21 of June.
COmetres JA and .6 CW has reen heard late eveniags but
Z1’'S and YVR'S have been providing most of the 7SR sienals,
40metrecs has been nuite good around 0600/0800&"'T with
V2rT strong at 07002. JA, b and some europcan stations have
been worked arown” this time on A% and ss3. throush J2 MR’
becomnee heesvy later in the eveninss.
20 metres.has-provided most 70 es usuzl., Iost of my times
on this bond havé becn between 0300/1100077 ¥/7, vmi, 71, W,
KCr, Kin, REY, VD8NG, ¥F, 424, 025, U1, 4V, have heen
heerd with strong signals mostly SS8™ eestern Cenadion stations
have been heard with very strong signals around 0500 T,
15 metres has provided openings on most dsys to JA and ©
during the afternoon.
10 metres has been lookcd st from time to time (maybe
ny 10 wmetre coil is oc. F7!I"Y reported very zood 10metre
openings in ! land last weekend.
73 Frank VI7RC
July 1975 ‘ QRIL- o Page
9
VFF NOTES BY JOE- VRT.Z0J
28 T mentioned last month you must be listening all the
time on six metes if you want a contect this time of the
year. .The calling frequencv of most stations is 52.050.
Phz, Tovin 770 worked TTAAAT on the 7/6/75 then on the
folloming - 2zkend worke A.Ti,“, both eoutacus only lasted
abou fwve miautes. .
Tisteaing on 52.050 this morning (22/6/75) at 0945 local
time T could hear Welly VR2Z.77 ealling C7 vig met ;. scatter.
I replied to his cell =nd exchaengel cellsigns with him, tiuc
taken to ccheive this was about 15 minutes. At 0715 I again
hezrd Yally calling C2Q signals this time were 5-9+ for about
three minutes we had three short overs exchanging 5-C and
-3 renorts.
Later on in the .sovning Bill VK7ZWK reported hearing
V22,V T tumsd. across Six and heard the following stations,
VEK's 4RO in Ayre 22iW, 2Z7L, 2BY(0, 4ZVC, back scatter, 2INS,
plus a C7 stetion and another stction in north "veensland.
Most signals peaked to 5-C with shallow 7SB, the opening
lasted for zbout one hour.
VHT activity in I.aunceston area on the tuneable portions
f the band isvery quict, Daniel VK7ZDA is in the process of
shifting QTH, and Kevin VI77ZAV hsas undertsken a twelve imonth
Study course.
Turing the month we had a couple of szood openings to V73
NDaniel temporarly erected a besm in his drive way and workcd
a larye number on 2 metcrcs SSB., We also heard a V{5 mobiles
in the Parossa Valley working VE7's via the "t Rarrow
repeater. Summing up activity for the montk considecring it
is the mid?le of winter it has becen rather plecsing.
73 till next nmonth JOE.
FILMS TO BE SHOWN AT NUXT NORTHERN BRANCH MSETING
1« FPROJECT BCHOs= 2Tminutes Colour Echo Satellite
Launched 1960, 100ft. circle,
Passive device used to reflect
radio signals, was the first
communication for satellitee.
2. WORLD BEYOND ZEROs= 30minutes Colour Shows World wide
tracking network in action observing
An Unmanned satellite from posts
at Cape Kennedy, Lima, Santiago,
Johannesburg, Anchorage, Winkfield &
Woomera.
Wally VKEBIX.
July %973 QyRalie Fage 10
* Part
2 VKN
By
Last month we ended by explainims the “RG" legend - we
should have concluded by stating that cable types not iden-
tified RG are primarily intended for use where application
is not met by sowme govermment type. Ur in ether words g
cheaper cable can be bought with the same specifications as
RG but i~ not bullet prvaf, sun proof or some other 8pecificat1on
as demand 4 1y armed services.
It o ~roposed this month to look at definitions as
applied to co-ax cables.
Attenuation < is loss of power expressed im 4F, and applies
teo to a glven length of cable at a given frequency.
i.e. RG 84 "7 has a loss of 5.5 dB per 100 foot
at 400'mH
Impedance is a term expressing the ratie of voltage to a
current in a cable ef infinite lemgth and is
meagured in “ohms impedance®.
Generally cables of three main classes are
asanufactured. i+.8.
50 ohms is RG8A/U Type cablo
70 ohmsisRG114/U *
93 ohms is RG62A/U "
etec, etce.
Capacity Capacity is the property of a system of conductors
and dielectrics which permit the storage of
electricity when a potential or voltage difference
exists between the two conductors.
#hen dealing with eo-axial cables the capacity
is usually expregsed in mmf or pf per foot.
Capacity is the major factor governing impedance.
The three cables we are using as exzmples are as
follows.-
RGEA/U - 50 Umms - 30 pf per foot 2pprox.
RG59A/U - 70 Uhms - 20 pf ©
RG62A/U = §3 Uhms -~ 13 pf * w "
Velocity is the ratio of the speed of the flow of an
electric current in an insulated cable to the
speed of light.
211 insulated cables have this ration and it is
expressed in percentage. In the case of cO-ax
cebles with polyethene dielectric this ratio is
65/@ to 6670.
Nesign In selecting co-axial cable we must carefully
consider use and application. 1t is hoped the
following V tables and coments are of use.
Design formula for characteristic impedance of
a single co-axial line isj
d = outside diameter of inner conductor
D =In§§d 1 “ outgide conductor
Zo = log 10%
where Z0 = Characterlstlc Impedance
E = Inside diameter of the outer conductor
D = Outside diameter of inner conductor.
> Page two (2)
Table 1,
T e
Dielectric Liaterial Dielectric Constant
Air 1
Polyethylene . FOALT Te5
9 - S6LID 243
TFE (Teflon) 2.0
Butyl Rubber (Generally
used in pulse cable) 3e1
oo
Another very important key to selection of cO-axial cable
is the required attenuation. In our hobby we usually try
to avoid this. But-in some facets we need to introduce
attenuation into a circuit.
The formula for theoretical Caltulstion of attenuation (4)
is the attenuation dus to conductors plus attenuation due
to the dielectrfi%
A+ 4.35 22w 208 & pf = dB per 100 ft.
Where Rt £ Tot§l:1ine: resistance ohms / 100 ft.
Rt = 0.1 ( E (for single copper line)
Pp = Powerfacgd& of dielectric (.0005 for polyethyleunc)
F = Frequency in megacycles.
As can be seen, dbtcnuation increases as the frequency
increases. In perfect cable the pattern of increasing
attenuation would be exact and regular.
However,; on the practical side this is difficult to
achieve and for this reason tolerances &r=z &pscifiadv The.
T e
RG specification spell out in detail the tolerances permitted
on various electrical characteristics.
Because the manzfacturers of co-ax cable is a continuous
process rather than a batch type process variations can be
expected on long leng ths of cable. These are usunlly detected
during manufacture by swecp ond spark testing. Cable not
conforming to RC specifications isvecut oub and sold under
some other number.
Looking at the basic Zo Formulas it becomes quite
evident th=t a few thousand of an inch difference in D would
significantly affect the impedance = and in the 50 ohms
minature group ofcables, tolerance becomes more important.
Even after the manufacturer has made the cable as
perfect as possible there still remains the practical
installation and use to which we subject the cable.
Power rating and other characteristice will be
affected by such things flexing, bending especially into
radius smaller than 20 Xiimes the cable diameter. '
Variations is atmospheric pressure and hear can also
greatly affect co-ax cable.
Earlier in this article we made reference to
"theoretical talculations®, in our hobby we ftry to bec more
“practically correct’ but = length of fair quality co-axial
cable can be relatively expensive when compared with the
rest of an airial systcm.
But given recasonable carc and in particular paying
attention to waterproofing the ends after installation such
2 lengthofcable will give years of trouble free service,
k
the alternative is a bad inc tallation and = length of cable
that corrcdes out in a matter of months.
[
TO BE CONTINUED.
W
J&T. GUNN PTY. LTD.
50 Brisbane Street,Launceston.
Telephone 2 2251
DOMESTIC & BUILDERS HARDWARE
MARINE & PLUMBING SUPPLIES
: PAINT & TOOLS
SEDDON PRESS
35\ GRANVILLE STREET, LAUNCESTON. 7250
Telephone 31 6191
for all your printing '
Business and Personal
’ QSL cards #ew#
- NORWIiNDg
ELECTRIOAL ENGINEERS
SPECIALISTHG IN MOTOR REWINDING AND ASSOCTATED WOEK
27 SUNCREST PLACE, RAVENSWOOD
' TELEPHONE 391515
Athol Lawes Electrics
135 HOBART ROAD, -
KINGCS MEADOWS, LAUNCESTON
: Telephone 443119
TRY US YOB YOUR NEX? APPLIANCE
YOU WILL FIND IT EASY ON YOUR POCKET $ $ §