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BULLETIN I3SUL BY THE INCORTHERN BRANCHES P.0. BOX 1010
OF THE WIREL THSTITUTE OF AUSTRALIA, Launceston
TAS. DIVISION Tas. 7250
JUNE 1975
VOL. 5 No. 3
REGISTZRED AT GPO HCBART for
transmission by post as a PRICE 40c
periodical._ CATEGORY B.
ITETINGS
June 10th North West Branch Iekins Hall Ulverstone 8p.m
June 13th Northern Branch Civil Defence Rooms,Bourke
Street 2 p.m.
Followed by Lecture: "The Strange Story of
Talse Teeth."
20 METLMTN AS
YRCS e
MBLT JG‘:D
June 14th
&
Kings ileadows High School 10 a.m.
June 28th
June 14th
& Lakins Hell Ulverstone 2 p.m.
&
June 28th
CONTESTS
June 1st Worked all Britain LF C7
June 21st All Asian DX Phone
June 28-29th ARRL Tield Day
SUBSQRIPTIONS
Subscriptions to the Northern Branch are now due
The cost this year is $2.50. If you are unfinancial
please fill in the form elsewhere in this issue and
return it to P.0. BCX 1010 Launceston without deley
if you wish to continue getting QRI.
. e A L.
June 1975 O.R.M. Page 2
Ladies Page
Pumpkin Pie (Enough for two pies)
Pastry:
+1b. Plain Flour
+1b, Butter
+ teaspoon Salt
Sift flour and salt, divide butter into 4 parts. Rub
one piece through flour., Mix with a little water to a soft
dough. Fold and roll out three times, spreading one portion
nf butter each time. Line plate or shallow pie dish. Cut
edges upward,
Filling:
Cup cooked pumpkin
NN-
eggs, + Ccup sugar
Cup Milk, 1 Oz. Butter.
Nutmeg, Juice of half lemon
+ pint whipped cream,
Rub pumpkin through sieve, add sugar, butter, lemon and
eggs one at a time and then milk, and lastly egg whites
~beaten stiffly. - Blend and-pour into pie¢ dish, Sprinkle with
nutmeg. Bake in fairly hot oven for 30 minutes, Top with
whipped crcam,
Bananae Loaf (Ideal for freczing)
3 mashed bananas
2 cup sugur
1 cgg
1% cups Plain Flour
1 teaspoon Carb. Soda
1 tecaspoon Baking Powder
6 tablespoons Butter
Mash bananas, gradually ass sugar. Beat in egg.
Sift flour, soda and baking powder and add to mixture and
lastly add melted butter.
Bake at 350° for approximately 2 hour.
(Better kept for a couple of days before cutting.)
Slice and sprinkle with butter.
.....r..;..u&.x.h__u__l._JL_!..@J,Ll..f'..[—ur..r_nr-nr-nmfi
¥ -0 DIiCisb
I found the May editorial of G.X.M. .ery thousht provoking
2nd as 2 resualt cffer a Tow observations. 4s these are persunal
I trust that they will not be consored and I cam get my message
sZecording to cvur licence we are all ameteurs or saying
it in eacther way the object of the excercise is 1o experiment.
n the Sunday morning broadcasts are in the neture of an
sxperiment. We are not public bruzdcasters. Therefore I can-
not see that, to juote, "Poor guelity does reflect badly on
the Institute®. Reflect tc whom? The brozdcests are directed
rimerily to amateurs and not to the public in genergl. oo
ey
et us go on erxperimenting even in thig field.
el
The first paragraph extols the virtue. of "those amoungst
us th. t are not appliance cperators", and later insists on
perfection in performance. e all know that amateur gear dues
ot always work that way (Murphy's Law) and so let us not be
o
toc criticel of those who are having a go.
My second obhservation ig directed to the referesnce to 7
cz1lls participation. This becomes necessary because full ezll
holders will not be involved im the Sumdey mornimg broadesst.
so the amswer is to get more full ealls. I cannot understand
why more limited lizence holdersg do not bother to Fimigh the
job amd qualify in Cw. 1if 3ll ealls in VL7 were full ones
there mould be plenty of statioms available for [Af broadeasts
snd ultimately elimimate the poor quality referred to, I for
one am always willing to help anyone 'O masber morse code.
If it does Zittle else this letter will help to fill one
of the blank spaces im Q.R.DMM.
oigned
Max VT
Page 4
June 1975
QRM
Northern Branch Notes
The May meeting wgs held at the Civil Defence rooms in
Bourke Street and attended by 31 members and visitors. It
was reperted that Council is prepared to pay the Licence fee
for the repeater VKTRAA in line with payments for the Devon-
port Beacon and the VK7WI licences,
A motion was passed thanking Joe Richter for his help
with the publishing of Q.R.M. over the past several years,
Feter VK7PF reported on the Federal convention and brought
to our notice the need to make a call on members due to lack
of federal finance.
; Further information may be found in the bulletin. Other
points noted were:
It is necessary to apply for the suffix /T to carry out
ATV transmissions,
The Wicen coordinator is VK1QJ who is to remain in
close tontact with Canberra,
There is to be a change in the Radio Act to allow for
maintainance of equipment to be sufficient guilt of illegal
activities,
There is still a hold up regarding clubrooms as we are
new awaiting a report from the Architects regarding the proposed
alterations and at this stage other possibilities are still
being loocked at.
Reg VK7KK, Lindsay VKT7ZLD and Robin VK7RH have offered
to help Robin with the display at the Museum,
Robin VKT7RH has offered to help anyone waiting to learn
morse and informed the meeting that CW practice is available
by tuning 3550khz at 7,30 p.m. each evening - the statica is
VK7BWI.
Members are asked to make known their preferrences with
- regard to social activities - I think this covers the main
points.
73's VKT74GG Graeme,
1975 Subscriptions Northern Branch
Please find enclosed $2.50 being subscription for Northern
Branch W.I1.A, Tas. Division.
NAl\m:oooulutoouolo...a.o....aon.‘QQQCALLSIG‘N:..QDUOuUOQA-o
ADDREss:.O..Of.I...‘QC.lI‘l.."....l"...Il'...l...l..l-..
€ 5 00020059 S TP T BP0 B80S0 L0 PO P B SS LNl e
Zune 1975 il ~eze 5
The meeting at Lokins Holl procneded smoothly with the
usual club statistics re-balance egg¢ a@nd a welcome extended
to vindsey Johnson of Ulverstone ~ho ig desirious of becoming
an assoclave.
It was proposed that council be a2pproached to eclaiify the
situation of official WIL.Q3. cards to be used at official
f.I1.A8. functions.
some dicussion ensued abflut the possibilty of Morse
practise on 2 metres and lax Til. agre-d to louk iato the why's
and whersfore's of a workable scheme.
Tony 7.« outlined conditions perteaining to the new
Novice licence.
Copies of the proposed style of exam were distributed
for persual znd as ¢ iistener I couldn't help wondering that
if this new sancticn is not 2 step in the wrong direction.
It is claimed by meny that it is at lewst a chance for
novices to build and align a tronsmitter and stand back in a
cloud of glory with the exclaimation/ I did it-. 4s I s:e
it this is not the case becaus: this can already be done under
he wing of a fully licensed amatuer. ‘he big question remains,
How many lads are keen on home brew? The trends of the last
few years indicate that there hasgs biuen 2 mase exodus from home
brew to store goovds so it does give us focd for thought.
Ls one who hasn't ccheived the coveted~ goal yet the old
By
gyst-m seemedto fil the bill acdequately :nd discouraged
murphy from getting his foot in.
Graham 724, gave an interesting tall on voltage regulation
using solid state.
oid 7ol zove a film show on the cepabilities of four
whee' drive and it left no doubui:s thet if you get stuck, its
the driver- not t:.e vehicle.
Closing commcnts: The next meeting is the L.G.W. there
shouild be 1006 attendance - health and duty permitting. If
you havent he1d a susition of office in the club, nowg your
chances to shca 'em.
Cheers - Reg. (Asseciate Member)
As stated, some thoushts are those of the writer and not necessarily of
the branch members. (Editor)
June 1975 QRM page &
VHF NOTES
There has been no sparotodic openings this month on six
metres. so I have very little to report, local activity ig also
quiet with the occasional contact on 52.525. Malcolm Salier
VK700 was heard lsst weekend on 52.050. the first time for several
months the only stations during the month were VK2BQJ on
meteor scatter VK7ZAH & VKT7ZDA.
Dont forget the mid-winter DX openings on six during June
they dont last long so you have to be arcund to catch a contact.
"hile on the subject of meteror scatter here is an extract
from a book I obtained from the library.
Meterors are small bodies, most of whicr orbit the sun.
Their orbital velocity lies between 11.3 Km/s (minimum velocity
for a solar orbit) and 72Km/s (the velocity required to
escape solar oravity). The measured meamn velocity is 40¥Knm/s.
On the other hand, the robital velocity of the earth is
arproximately 30Km/s. :
At 0600h local time at the point of observation, the
orbital velocity of the earth is directed towards the zenith,
and the relative velocity of the earth is directed towards
the zenith, too. and the relative velocity of meterors 1n
relaticn to the atmosphere -i:. between 41 and 102 im/s wita
meon value of 70 Lm/s. At 1800h local time at the point of
observation, the orbital velocity of tiue eartin is directed
towards tiae nadir, and some meterors are unable to catch up
with it, waile others arrive at velocities between O and 42 /¥ns
with a mean v.lue of 10Ka/s.
Therefore, the mumber of meterors encounted and their veloclity
are counsiderubly greater at 0600h than at 1800h.
The deceleration of meterors by the relatively low laysrs
of the atmosphere produces intense heat, which causes their
combustion at a srcater height and wmore ra_idly if their initial
velocity was greater. The coumbustion products are Ioniscd
and form & meteoric trail that is capable of reflecting radio
waves. Very thich trails can be seen withh the naked eye at
the moment of their formation meteoric lonizaticn occurs at
altitudes between 80 ci:d 100Km, with a maxiuum ionization
occurs imuiediately after the trail formation altitudes betieen
has been formed; the trall then beoins to expand and to
diffuse cutwcrds. Its electron deusity decreases and 1t is
no lonzer capable of reflecting Ligh frequencies.
At the scme time, the trail is distorted by atmosdhere
disturovences. In the cuse of 2 larce meteor, the nead of
the trail reflects a considcrable amouvnt of energy. Because
of the motion involved, tuails reflection occurs withh a change
in frequency due to Doppler effect. VWaves reflected by the
head of the trail interciere with thnose reflected by the vody
of the trail, taereby ascends ag.iu. On 52 Lihz is sounds Like
afring",
I hope you have found the above interesting and you now
know why one carries out meteror scatter contacts at gsucih
an unearthly aour.
Two meverors still _rovides openings to V.3 via out
our re_eater on these foggy wornings also if you live in a
good location you can work tarough the VL3 repeaters,
73 till next month
JCE. VK72ZGJ
.
June 1975 QRM fage
7
fazt Ume. CO- AXILT ZLBL.3......Some thouzhts
TNR style.
Wie spend time cnd money genercting R.F. and then
feed it into & "CABLE" which we hove will carry it to our
radiating devices for onw.rd transmission or 1nverselJ we
connect that super duper receiving device to the same
ceble, and esre disaprointed atthe results.
That cable I refer to in this instance we know as
"Co-ax". The following comments are intended to give e
better appreciation of Co-~axial cable.
For the younger members it is necess ry to give a simrle
explenation of the use znd developement of co-asial cable
and we use here as an example a common telephone circuit.
Trensmission of signcls over wire lianes requires two
conductors to complete the circuit - the ""go" wire end the
"return’ wire. In som2 telephone aprlications only the
"go" wire 1s mounted on the pole, and the e.rth itself is
used ¢s the "return® wire. Or pzirs of cables can be
bundled together to form & multi pair cable.
‘Thatever the err.ngement, these wires carryiaz the
very delicate electrical curreat: conveying the telephone
conversion are exposed to external interference, lightn-
ing which caus~ sf::lc, wet weethe: cc ises Weaka € across
conductors «77i.° o frying noise, foults on power lines
cause plops, buzzes end hums, a2nd the vroximity of other
cable c¢irs to your neir zives ancther nroblea dnown as
"eross t.1k". These cre some of the nroblems we call
n T T
W e R o N o
Two other major problems relate +to the use of ".able
pairs” the first is attenuation, thet is the signal get
we-sker, the lounger the wire circuit, so thet amplifiers or e
needed every 30 miles or so th keep the iant lligence above
the line ncise.
The other problem and vnerhans the wost 1nportcat of the
two is that of "Band Width". Telephcne ronversion c.n be
gatisfactoraly carried if the audible tones can be kept
in the range 300.C.P.S. To about 2.7 K.C.S. It is zlso
poscidle to carry more than one conversion simultanecusly
on a pair of wires by "Frequen~y Multiplexing" the conver-
gations.
In this gystem e:ch conversation occupies a hand width
of approx. 2700 cycles with a guard band 500 cycles between
each channel tc prevent their mixing.
Because of the relatively low upper limits of frequency
that a pair of wires can carry simultaneously we rannot keep
adding the number of conversions infinitum.
June 1975 Q.R.M. Page 8
Tart one crntin....
Co-ax cable was develo ed primarily
to alleviate the fcrezoing vroblems.
In co-ax cable the "go" wire is the center conductor
around which is placed = heavy insulatcr. But the "return"
wire is no lon-er another identical wire, inste:.d it takes
the form of a copper tube, either braided or drawn over the
insulator and completely surrounding the "go" wire and insul-
ator and concentric with it. Hence the term co-axial.
Because of it's ccnstruction no external interference
can affect your conversation (when used for telephones;
because the ~urrents are completely sheilded by the "return"
(Braid) conductor.
If properly protected and sealed enen the effects of
weather are excluded, all though zttimes co-oxial cables
buried four feet down are STRUCK!? by lightning.
Co-axial cable has an extremely broard band width, and
id capaple of carring signals from zero frecuency to many
mHz.
Hundveds ¢f rnonversations can be frequency multiplexed
and transmitted =t the same time over a single co-ax cable and
because of it'c low attenuation =zt these frequencies fewer line
amplifiers =ve needed. Those that are required are relatively
cheap because they can woost all signals on the line dimultan-
eocusly.
The uses of co-axial cable extends to any application in
which signals lose, and attenuation must be kept to a minimum or
in which the elimination of outside interference is desirable
and important.
Identification by type numbers.
In this article I can only comment on cables made strickly
tc U.S. Government specifications and marked with the legend R.G.
What does this mean, using R.G.8 A/U as an example.
R means Radio Frequency.
G means Government.
8 is the Government approval no.
A means 2 Specific modification or revision.
/U means it is a universal type.
You can except to identify a cable the legend doesn't give
any technical details - Current wire tables run from RG1 to
RG325 so it is not possible to publish all this information in
Q.R.M. ©Should you require information on a particular cable
give me a call - I might be able to help.
TO_BE CONTINUED.
June 1975 QM Page 9
------------------- FOR SALE FOR SALE —memmemmmmememmm
Home brew cw Transmitter geloso VFO $ 70.00
Home brew receiver plug in coils ¢ 50.00
Or both for ¢ 100.00
6 metre tranistorized convertor (vK3) $ 8.00
Coil winder
All in going order.
Contact ED VKTHE
Phone Lesunceston 391 863
FT 200 just been tuned, hass several new tubes
Home brew power supply }
Three transformers instecd of the usual one $ 350.00
Contact Ross Broomhall
27 Suncrest Place
Phone Launceston 391515
Book shelf spe ker enclosures 1 cub.ft. contzaining five
and six inch twin cone speckers professionelly constructed
Speaker =lone co’t this much..
AW,A, . 50_watt bese stet on on 52.525 mhz. $ 59.90
I.G.L. receiver 98% complete $ 20.00
-has been operationrl, missing mpf1z1 2nd one I.F.
transformer.
Wanted to but "STOLLEE" o:srial rotetor or similiar.
Contact Joe VKTZGJ.
40 Lavender Grove.
Phone Leunceston 443882
THE, WHAT, WHERE, WHO, HASSLES & HOW MUCH
BOOK
'No emateur should be without one!
An invalu be reference to those many firms of interest to
electronics end communications enthusissts. The complete
component & equipment source book. .-
Over 250 firms listed, plus meny books and megezines, in
20 cetegories. )
Lively, informative reading.
ONLY $2.80 post poid
(p/o's preferred)
FROM: AMATEUR CCMMUNICATIONS ADVANCEMENTS
47 ballacst Point R@, BIRCHGROVE 2041
June 1975 QeR.M, Page 10
HF Notes for June 1975
The HF bands have, with the exception of 10 metres been
quite good for DX despite the sunspot cycle situation. The
crop of HF centests have produced plenty of activity over most
weekends and some usually rare countries are obtainable for those
of us who look for them deep down "with the cans on".
On 80 and 40 metres the following countries have been worked
during the evening and early mornings VE7, VE8, VO1, G, GC, D,
HB, VP9 and other mornings during the early evenings with the
control and Southern Americas coming in later.
20 metres as usual carried most traffic and has been open
most days until late evenings when good DX can still be worked
by using the cans and a hey!
15/10 metres have not been watched much from this station this
month but is usable for DX most days if conditions are fair,
A good opening was into 4L on 10 metres during the morning
of the 20th.
VK7BC Frank,
Looking Back
Extract f£rom minutes of the Northern Zone held on 14 June 1963,
"The next item on the Agenda was the amendment of the Zone
RPules and the President read the rules and each rule was
discussed fully (sometimes at both ends of the room at once)
and from the many suggested amendments and amended amendments
the following alterations were finally decided upon after
Ccl 7LZ had warned of the tendency to overgovern."
Extract from minutes of the Northern Zone held on 16-June-19:/ .
"Following complaints by some members that the activity of
Launceston Amateurs had become very psor in recent weeks,
it was decided %o hold a weeckly VHF net for which Prisident 7PF
chose lionday at 1930 on the 6 metre frequency to be the most
suitable arrangement, with a further 2 metre excrcise to be
arranged by members at a time which was mest suitable."
EEHKX KK KKK KRR A KKK KT A TR AT H R TR TR R KRR KHHXREXX K HXHX
FOR SALE ¥#¥%xx*x%x¥ »OR SALE *%XXXX%% POR SALE *¥*¥¥%¥%x%x% FOR SALE **%X¥%%%
9 element Sun Yagi - $11
ALSO wanted 5.8 mHz crystal.
CONTACT ¢ Frank Beech VKT7BC
Nobelous Drive
Legana
Phone 301379
FT-620B
® VHF DX is Now Achievable with the FT-6208 VHF SSB'Transceiver
Join the action and DX on 6 Meters with our new, all solid offset clarifier, and an effective noise blanker; all add up to
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features, in one compact unit, complete band coverage in supply adds to the portability of the FT-620B transceiver.
eight, 500 KHz segments with 1 KHz VFO readout across Add up ali the features, and you have another total
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Specifications
GENERAL Power Requirement: 100/110/117/ Automatic Gain Control: AGC thresh-
200/220/234 V- AC, 50/60 Hz, 60 old nominal 1 uV. Attack tine 5 milli-
Frequency Range: 50.0-50.5 MHz, Watts maximum, or 13.5 ¥ DC nomi- second and release time 1.5 seconds.
50.5-51.0 WHz, 51.0-51.5 MHz, nal, 0.3 A for receive and 2 A for Audio Noise Level: Not less than 40
51.5-52.0 MHz, 52.0-52.5 MHz, - transmit. dB below 1 Watt,
52.5-53.0 MHz, 53.0-53.5 MHz and Size: 280(W) x 125(H) x 295(D) m/m. Audio Qutput: 2 Waits 1o internal or
53.5-54.0 MiHz. (For 52.0-54.0 MHz Weight: 8 Kg. external speaker at 4 Ohm impedance.
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RECEIVER Audio Distortion: Less than 10% at 2
Mode: Selectable USB, LSB, CW or
Watts output.
AM, Sensitivity: 0.5 Vv for 10 dB Noise
Frequency Stability: Within 100 Hz plus Signal to Noise Ratio on SSB and
during any 30 minute period after
TRANSMITTER
CW. 1 uVon AM.
warm-up. Not more than 100 Hz with Selectivity: 2.5 KHz nominal band- input Power: 24 Watts PEP on SS8B,
10% line voltage variation. width at 6 dB.down, 4.1 KHz at 60 dB 20 Watts on CW at 50% duty cycle and
Calibration Accuracy: 2 KHz maxi- down on SSB and CW. 6 KHz nominal 8 Watts on AM.
mum after 100 KHz calibration. bandwidth at 6 dB down, 10 KHz at Microphone: 50 K Ohm dynamic type.
Backlash: Not more than 50 Hz. 60 dB down on AM. Carrier Suppression: -40 dB.
Antenna impedance: 50 Ohm unbal- Harmaonic & Other Spuricus Response: Sideband Suppression: —~40 d8.
anced nominal. Image Rejection better than 60 dB. Spurious Radiation: ~60 dB.
Circuitry: 35 Transistars, 7 FET, 2 Internal Spurious Signal below 1 uVv Distortion Products: --25 dB.
Integrated Circuits and 40 Diodes. equivalent to antenna input. Frequency Response: 350 {0 2700 Hz.
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