QRM
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i
i
Bulletin issued by the Northern P.O. Box 1010 i
Branches of the Wireless Institute \ Launceston
of Australia, Tasmanian Divigion. Tas. 7250 /
August 1976
Vol.6 No.5
Registred at GPO Hobart
for transmission by post Price 40¢
as a periodical. Category B.
MEETINGS_ N (5
. o TN
Aucgiust 10th North West Branch, Lakins Hall, Ulverstone. 8pm
August 13th Northern Branch, S.E.S. rooms, Charles St. 8pm
_Y.R.C.S. MEETINGS
August 14 & 28 Kings Meadows High School, 10am
A.0.C.P. Classes
Aucgust 9th Kings Meadows High School
16th block B, room 35
23rd Cw, 7.30 pm
30th Radio Theory, 8 pm
CONTESTS
August 14 & 15 REMEMBRANCE DAY CONTEST
August 28 & 29 All Asian CW contest
September 11 & 12 Furopean Phone Contest
September 18 & 19 Scandinavian CW Contest
August 24th Deadline for the next issue of ORM
Page 2 Q.R.M, August 1976
Notes from the Northern Branch by Norman VK7NR.
The president Brian VK7ZBY and 30 members were present
at the July meeting of the Branch. Byron Dillworth was
congratulated on passing the AOLCP and being allocated the
call sign VK7ZBD, a call which is being used quite successfully
on the repeater channel.
Johny Victor is still seeking articles for QRM and
some news from the Ladies. Did you see last months Ladies
Page effort ?
It is hoped that by the next meeting a progressive
dinner will have been organised. This will possibly be free,
but you will pay for it later at a Bingo Night, which is also
being arranged.
Last months questionaire in QRM regarding the clubrooms
was reasonably well supported. Bill VK7TE has so far received
35 replies. Those not filling in forms will receive a visit
from Bill. DID HE KNOCK ON YOU DOOR ?
Ed VK7HE mentioned a new modular method of construction,
which could bring down the cost of clubrooms if used.
It is amazing how many regulation books were sold at
the meeting. This is a publication you must have. Ever known
a Parson without a bible ? (Yeah, a Rabbi.)
Good news regarding the Hamfest site, Evandale council
have approved a small number of sites that can have caravans
parked on them, just behind the Hall. So if you are bringing
up a caravan let Lindsay VK7ZLD know now and book your place,
write him C/o P.O. Box 1010 Launceston. As these sites are
only yards away from the Hall and are free, its first in first
served.
John Beswick prsented his application for a student
membership, which was approved. Welcome John and good luck
in future exams.
Heard the new VK7RAA ident yet? No complaints please,
but its inventor can be congratulated, apparently it achieved
the object of not annoying certain people on the ch4 to 80 m
relay of the Sunday Broadcast. The idea is that 2800Hz
doesn't get through the narrow filters of SSB tranceivers
during the rebroadcast. Most 80 metre listeners did not hear
it on the first Sunday following its instalation, but one
character did report key clicks and was about to tune the
band to find the offender? Has he got a crook rig?
Mark Addison at cosgrove Park listens to VK7RAA with
an Icom generously loaned by Tony Polowy. So say '"good day"
to him when on air Also have you been in and had an eyeball
QSO yet?.
If you did not get your application in by July 8th
then you wont be sitting for the next AOCP exam. If you did
then good luck and may you make it. VHF is a bit quiet
lately, we could do with some more activity, CW classes
these days can be heard on 27 MHz when conditions are right.
It would appear certain gentlemen are keeping their hands in,
pending the results of the first Novice exams. Some marked
papers could help to curb this activity, or will it ?
cont. page 4
August 1976 Q.R.M. Page 3
Notes from the North West Branch.
The monthly meeting was held in Lakins Hall Ulverstone
Tuesday the 13th of July, commencing at 8 o'clock. With the
President, Ian VK7ZIE and the secretary Max VK7MX in the chairs.
This would be one of the best attended meetings we have had for
a long time, the 28 members and 2 visitors present, although
the night was cold and frosty it didn't stop the good turnout.
I think this speaks for itself, as I have said before that the
interest here in the North West Branch is now very keen.
The meeting opened with the president welcoming the
2 visitors, Paul Stott and Tony Smith. Then the secretary
read the minutes of the last meeting, correspondence and the
treasurers report, he then called for a motion for these to be
passed which was duly done. The president then asked the
various Branch officers for their reports on their jobs within
the branch. Adrian VK7ZAT, the equipment officer, reports a
lot of new stuff on order of which only about half has turned
up. Winston VK7EM reported that everything was o.k. with the
beacon. Harold VK7MZ reported that everything was o.k. in the
QSL depatment, so everything seems to be running well in the
Branch. Towards the end of the meeting the president reminded
all present of the forthcoming Hamfest at Evandale on the 13th
and 14th of Novembesr. With a special request for VK7MX, VK7KH
and associates Jim Davies and L Johnson to turn up.
If you will recall these are the members who in the
sand at Port Sorell, at the mini Hamfest ware the stars of
the cricket match and were responsible for the trophy coming
to the North West, the trophy was on display at the meeting.
The meeting closed at 8.35 pm and was followed by a
very interesting and informative lecture by Pat VK7BW, an
American from New York City who now lives and teaches at
Latrobe. Pat lectured on 27 MHz activity in America, he also
gave some comparison on life and prices compared to here and
New York. It's quite amazing to learn of the amount of 27 MHz
activity in the States today, really fantastic. Pat lectured
in quite a professional manner and answered the many questions
asked by the members present.
At the end of Pats lecture Max VK7MX thanked him on
behalf of all the members present and himself and expressed
the hope that Pat could again lecture us sometime in the
future. )
Supper was then served by the Burnie and Wynyard
members and the evening closed at 10.45 pm. With the usual
2 metre activity by the members, mobile on their way home.
Lindsay Johnson
-0-0-0-0-0-0-0-
FOR SALE; Multi 7, 23 channel 2 metre FM tranceiver, includes
12 sets of xtals (repeater 1,2,3,4,5, anti repeater
1,2,3,4,5, channel 40 and 50) ,Belling and Lee 1/4
A
whip and microphone $190.00
contact Phil Thompson, phone (work) 002-208684
(home) 002-285998
Page 4 Q.R.M. August 1976
Bob VK7ZRF is working on a Fox Hunt receiver but
declined to express his thoughts at this time. Better hurry
Bob or the season will be over.
Almost forgot to mention that professor Ellis will
be giving a lecture in August. All members are invited and
your scribe believes the subject is RADIO ASTROLOGY. Should
be interesting. More details when date and venue are known.
Well that about winds up last months meeting notes,
exept to say that Ed VK7HE's lecture on Disaster Communication
Principles raised a few eyebrows and had people wondering what
mother tongue you should have to become a member of S.E.S.
communications section. Plain English apparently is not
acceptable.
At the next meeting Wal VK7ZWX will present two films
both marked, for general exhibition.
73, see you at the S.E.S. rooms
on Friday 13th of August.
Norman VK7NR
khhkhhkhkkhkkkhkhkhhhkhkhkhkhksh
We would all like to extend our congratulations to
Ian VK7ZIE and XYL Lyn on the arrival of their daughter Jodie,
their little harmonic and who knows perhaps sometime another
on air member of the Ellings family. In fact she has already
been on 2 metres, she was heard by an Ulverstone member the
other day while being held up to the microphone by Daddy ZIE.
I'm told one of the first things she must learn is,
how to operate and use that infernal washing machine, this
will get Daddy out of untold trouble if Lyn is away sometime.
Also Lyn, I feel you owe Graeme VK7ZAQ a big thanks, you
could have had a big pile of washing to do when you arrived
home from the hospital. Anyway good luck to you both with the
family raising, stick to it and who knows, one of these times
it may be two perhaps.
Lindsay Johnson
eo e eok ootk g eok okok deokok ke ke e e
FOR SALE, Playmaster, quadraphonic amplifier 15W per channel
. $150.00
P.E. turntable and base $100.00
B&0 cartridge, J&H belt drive turntable
and all balance arm $65.00
RCA remote control unit $8.00
6UP, 432MHz converter with AF139 pre-amp $10.00
Marconi standard signal generator TF1446 $30.00
16 el, Sun Yagi complete with matching
stub and 4:1 balun, ready to go. $35.00
Joe Gelston VK7ZGJ, 40 Lavender Gr. phone 443882
de e ke kKokokode Kk kokokok Kk okokokok ok okok
August 1976 Q.R.M. Page 5
HF and DXnotes byColVK7LZ
Although listening this month has been limited it does
appear that conditions have been well below that of June.
The only DXpedition heard here was K5QHS/FHB8 operating
from the Comoro Islands on the 29th of June, 14 MHz SSB
signals were 5/5 however this station is now QRT.
14 MHz., 1In the afternoon this band was usually open to W and
VE with good strength signals, the Pacific Islands were also
represented by VR1AF, VR8A, KJ6DL, VR3AH and VR3AK most
afternoons.
Infrequent listening of an evening has also produced
UAg's and JA's with the one exeption - JHIKSB/JD1 Minami
Iorishima activates C.W. around 07.00 Z usually about 14.030
Mhz.
7 MHz. Was also down in activity, only 27 countries were
heard against 39 the preceeding month and it appears to be
necessary to be listening from approximately 05.00Z for
Europe and Cetral on Northern South America., On SSB G3A00
and the odd European can be heard, usually in QSO with VK's
on sked. On CW the best of those copied were;
0500 to 05302, HB9BAJ, SP2HJL, DK3FB, YU2CEJ, F3NB, F6ARC,
VP1MPW, CE3AKX/TI2, GC2LU, YV4CB,
0530 to 06002, CO2SM, also W, VE, G, F, YV, EA.
0600 to 0700Z, YV3AGT, ZL3LN/C, YV1AD, 8P6GO, XE1BGM, FGT7AM,
HK@BKX, CM2VG.
Later in the evening its mostly W, VE, JA
and UAg. One gets the impression that lack
of activity is more of a problem than conditions
at times on this band.
3.5 MHz. From the odd listening periods it appears that JA's
and W's can be QSO'ed during the local evenings on CW but
the only unusual station copied was -~ YB7HB who was 449 at
1300Z on the 1st of July.
1.8 MHz, Very little DX heard, listening between 0900 and
1100Z the only stations logged were; VE7UZ, W1HGT, W4EX,
WABIJI and LU1DZ. JA3SVG/MM who is operating from an ore
carrier (not whore) is also active on CW and has been QSO'ed
by some VK7's but you have to listen for him between 1907.5
and 1912.5 MHz., -
As the Seychelle Islands become independant this year
and as the new administration will include the islands of
Aldabra, Desroches and Farquhar there is a good possibility
that these islands will be deleted from DXCC country status.
QSL information. KJ6DL via WB5S5HVY
VR1AF via W70K
VR1AH wvia VK&JW
VPIMPW via W50QPX
YB7HB, P.O. Box 2761 Jakarta, Indonesia.
FG7AM, Box 957 Pointe a Pitre, Guadeloupe.
K5QHS/FH8, P.0O. Box 2388 Hot Springs, Arkansas 71901 U.S.A.
Page 6 Q.R.M. August 1976
VHFnotes by Joe VK7ZGJ.
Although it is now mid winter VHF activity has been
rather high. There have bheen several openings on 6 metres.
On 27th June Kevin worked VK2ZKY, on 6th July the band opened
to VK2, stations worked ware VK2ZFB and VK5SU/2 in Moree,
Kerry is using a 40 metre dipole. John VK7JV was also active
and worked several stations.
Again on the 22nd July I worked VK2ZAY, VK5SU/2 and
VK4ZTW. On the 20th July ZL TV was watchable for about 1 hour
between 2000 and 2100 hours, I could not hear their beacon
and no contacts were made,
2metres has been good with numerous openings via the
repeater. At the bottom of the band VK3YJU was worked by
Kevin VK7ZAH on the 16th July. On the 21st July there was
a very good opening as VK3's BQR and ZX0O were worked, a 6 - 2
metre crossband QSO lasted for over an hour between VK7ZAH
and VK3ZXO. Allen VK2ZEO in Deniliquin worked Max VK7MX
and Winston VK7EM on ch 40. Ron VK3AKC was worked on the
22nd July by Kevin VK7ZAH,
432 MHz, John VK7JV is now active on this band,
running approximately 200 mW to a 16 el. Yagi. We worked
on the 4th July exchanging 5/5 - 5/9 reports, I was running
a valve rig at the time but will soon be active with about
25 W solid state.
73 till next month
-0-0-0-0-0-0-0-0-0-0-0-0-
Capacitors suitable for high power RF solid state amps.
In most application notes a reference is made to "metal
clad mica capacitors" these are expensive and very hard to
obtain in VK, typically $1.50 to $1.80 each.
It appears these items are only mica capacitors with very
heavy strap leads and a thin wvarnish or wax protective cover.
Removing from the junk box a few old mica capacitors and
removing the brown bakelite cover it was found that the
construction of these capacitors was very good for VHF low
inductance use by just soldering the end plates direct to the
circuit board. ‘
Col VK7KW
_.—0ld lead
strap end
plates, solder
direct to cct board
mica stack
August 1976 Q.R.M. Page 7
PROGRESSIVE DINNER.
The progressive dinner will be held on the 4th of
September, starting at 6.30pm at the QTH of Wally (VK7ZWX)
and Shirley Morphett, with pre-dinner drinks and appetisers.
The next course is soup (choice of two) at Ed (VK7HE) and
Noeleen Hewens place, then to Gordon (VK7GW) and Moira Woods
for the main course and to finish, sweets and drinks at the
QTH of Reg (VK7KK) and Annette Emmett.
To cover costs there is a charge of $5.00 per head.
Tickets to the dinner will be sold at the August Branch
meeting and thereafter will be available from the secretary
Norman VK7NR up to the 2lst August.
Annette Emmett (Mrs VK7KK) is interested in starting
a Ladies Committee of the Northern Branch., with the view of
organising social functions. First is the Hamfest which is
just around the corner. Anyone interested plea2se contact
Annette. Phone 312090
Northern Branch Equipment Store.
See Daniel Apted our equipment store officer for your require-
ments. Components in stock include, transistcis, resistors,
capacitors, diodes, neosid (full range). VHF <F chokes,
RF screening beads, coax connector. (BNC, PL ~eries, B/L),
single and double sided printed circuit board.
Kyokuto,2 metre, synthesised FM transceiver as described in
Amateur Radio July 1976, . This unit covers the entire band
from 144.0 MHz to 148.0 MHz in five KHz asteps and includes
a 600 KHz offset, up or down, for rep<ater use . Frequency
readout is LED digital. The store can obi i these units
for you, cost is $300.00
We still have a few meters left, 200 uA mov-rent 80¢ each
Morse practice keys $1.20 (5 only)
The equipment store also handles all orderc for equipment
as advertised by,Sideband Electronic Sales, Vicom and
Amateur Communications Advancements, thig i1nciudes orders
for all types of HF and VHF transcocivers. tiansverters,
converters, aerials, frequency counters, CRO':z, aerial
rotators,crystals and crystal filtcrs. Although costs are
about the same as advertised, there are two advantages to
the members, you don't have to pay for your purchases until
you actually take posession and the Northern Branch gets a
small commission to boost funds.
The store is also able to handle all sukscriptions to
amateur type magazines, technical books as handled by the
WIA, logbooks and call books.
For further information contact the Eqguipment store officer
Daniel Apted VK7ZDA, 31 Vale St. Phone 44688ec or to
P.0O. Box 1010, Launceston.
Page 8 Q.R.M. August 1976
TWO TONE OSCILLATOR, 700 Hz and 1700 Hz.
-
This aricle was recelved from Charlie VK3ACR and
is described as been very stable.
The 1700 Hz and 700 Hz outlets are anly required if
you need seperate outlets, you will note that you get the
same effect if you swing the balance control from one side
to the other to get seperate frequencies.
The tab pots are for adjusting the output of each
oscillator, I found that the central position is about right.
The tab pots are of the 30¢ variety although they could be
replaced by 250K fixed resistors if you like , taking the
output for the balance control from the end farthest from
earth.
Transistors; 2N706, BC108, +3—6 Volts
2N3566 or similar et iy .__J-
) switch
Capacitors; green caps
}%§\A 15K
<,
j:.OZ
.01 ° .01
“_%I___fl
1K5
1700Hz EE~WM~—‘ 700Hz
MODERN SOLID STATE CONVERTERS
VHF Modern solid-state, high performance converters
for 28/52/144 MHz bands. Featured in Feb
GONVERTER opoiiee
28MHZ/ETI707B . .........ccoovvn.... 1
S52MHZ/ETI707B ..................... $11
KITS 144 MH2/ETI707A ... 00000 $14
These converter kits are simple, easy to construct and align.
® 28/52 MHz (ETI 7078)
Th's is a tried and proven design and was featured in the January
issue of ELECTRONICS TODAY INTERNATIONAL. Noise figure
on 10 m cr 6 m is a little meaningless but this converter produces a
noise figure of around 2 dB. Gain is 20 dB or greater, bandwidth is 3
MHZ on 6m, 2 MHZ on 10m, spurious responses — 50 dB or better.
Chuice nf IF frequencies to suit yourself. Please specify 28 MiHz or
5" MHZ operation, Crystal not supphed Fibreglass p.c. board. Value
. $11 or just the p.c. board
.. . $3.10
® 144 MHz (ETI 707A)
Naturally another simple converter. An original 6 UP design, this was
also featured in the January 1976 issue of ELECTRONICS TODAY
INTERNATIONAL. This converter was designed for low noise (3
dB or better) and low crossmod. performance. Gain is adjustable,
with a maximum of about 20 dB. Bandwidth is also adjustable
between about 0.5 MHz and more than 1 MHz. Spurious responses
are down 50 dB or better. Choice of IF frequencies to suit yourseif.
No neutralization. Crystal not supplied. Fibreglass p.c. board. What
more could you want for. .. $14 or p.c. board only ... $3.50
o ® 432 MHz (6UP-004)
The famous design by VK5QZ — now a standard of sorts! Improved
p.c. board. This is probably the simplest way to begin on the UHF
bands. A simple and straightforward design that produces good
performance. . . noise fiqure approx. 4 dB, JFET front end, gain of
10-15 dB, IF of 28 MHz or 52 MHz although some constructors
have used 146 MHz successfully for FM net operation. Bandwidth
approx. 4 MHz, Fibreglass p.c. board. Crystal not supplied.
Complete with straightforward instructions. Head for the frontiers
for...$14 or p.c. board only ... $3.35
e MARKER (6UP-006)
+
This provides harmonics to 1296 MHz from a 1 MHz crystal or to
432 MHz from a 100 kHz crystal. Can accept crystals to 15 MHz. "
Uses 5 transistors. Crystal notsugplled Find the band edge o
for. . $7 or p.c. board only .
PACK & POST on kits is 60c per Kit.
CIRCUIT
send s.a.e. for details on coil components,toroids,baluns & other
kits and components
THE WHAT WHEREWHOHASSLES & HOW MUCHBOOK
(OTHERWISE KNOWN AS “THE AMATEUR'S PINK PAGES™)
A COMPREHENSIVE COMPENBIUM OF COMPANIES AND COLLEAGUES THAT
COLLECT CURRENCY FOR COMPONENTS; SELL SOCKETS AND SWITCHES
OR SUCHLIKE FOR CENTS; ARRANGE ARCLIGHTS OR AARDVARKS FOR a paltry
ARDENT AMATEURS; FLOG FT200s AND 4X1000S....ccccvevurecnsaoas $2 0 :
in fact, if you have ever wondered where to get something, 5
or perhaps where else, then this book is for you. It does +40c Post
not cater only for those who build lots of gear - even if you
only read about amateur radio, you need this book. It also
tells you where to get the things you like to read!
AMATEUR COMMUNICATIONS
ADVANCEMENTS
P.0. BOX 57, ROZELLE 2039
Page 10 0.R.M, August 1976
Some practical thoughts when considering a vertical aerial.
byTrevorBriggsVKJTB=
1) The need for an omni directional aerial.
2) The need for an aerial construction that is practical.
3) An aerial that offers a low angle of radiation.
4) Some improved radiation efficiency over a simple b% vertical.
5) An aerial that can be resistively terminated to a piece of
transmission line without too much of a mechanical problem.
The aerial construction that satisfies the above
requirements is the 5/8A vertical aerial. A 5/8)\ vertical when used
on any band (whether VHF or HF) has a very useful radiation
capability.
Lets consider the above items individually,
Items 1 &2, are virtually self explanatory and require no further
thought at this stage.
Item 3, An important consideration when selecting an aerial system
is the angle of effective radiation. The 5/8A vertical offers
the lowest angle (for part multiples of aX) for a given aerial
lenght.
Item 4, For a properly terminated 5/8 A whip with a satisfactory
ground plane, it is possible to achieve an increase of aerial
gain of 3 dB over a conventional 1/4A vertical aerial. This then
must increase the relative radiated power from the aerial.
(see diagram) '
s0°
(max. low
angle of
radiation)
Relative power
Item 5, A 5/8 vertical is a little more difficult to terminate
than a 1/4 vertical, but never the less this can be achieved
without too much difficulty.
A 5/8 wvertical is a non resonant aerial and it has
a base impedance which is quite capacitive reactive. So two
problems exist, (1) the propagated electromagnetic energy from
your transmission line will see a non resonant aerial and (2)
it will see a value of Xc as a high 2, I think you will agree
a most unsatisfactory situation.
The method in overcoming these problems is first to
fool the R.F. into seeing a 3/4 aerial so it will be absorbed
from the transmission line and radiated by the aerial (now
effectively resonant). This can be achieved in several ways,
-
August 1976 Q.R.M. Page 11
In diagram (a) the large Xc has been balanced out by
the coil L enabling a resistive termination to be made. However
the termination Z may not match the Zo of your transmission
line.
(a)
T
|
. / e e
7 >\ ZAsSE Zoic
ys
A oto
£
FM-_
L owhrw XL = Xe oF 5:;;% AERial BAsE Z
o]
Xe oF 5"\7\
Hign Z /8 } RESIsvANEE TERAMINATION OF ABowT 50_70 o
VERTICAL
-ll}————o
Non ResoNANT ,
(Tyrical 7 orF %* A ,qsfl,,q}.)
It is important to note that the L is used to effectively
balance out the high Xc to give you a resistive termination
at resonance and that L should not be adjusted to improve the
S.W.R., for this reason a more tlexible matching system is
shown in drawing (b).
(b) ] X1 = Xc, a high value of R is
! seen across a parallel resonant
Sg )‘ circuit.
With careful adjustment of C and the position of the tap a
resistive transformation occurs between Zo and the base
impedance of the aerial. A low S.W.R. can be obtained with
this type of matching system.
Trevor VK7TB
\ ’
[ treet,Launceston,
50 Brisbane S
FTY LTD
Telephono 2 C6]
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