QRM
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Amateur
| Radio \ MAY
News
Issued by the Tasmanian Division of
the Wireless Institute of Austrolia
(INSERT TO "ALR.")
Radiotorial.
We have tried for two months now to distribute "QRM" via
your copy of "A,RY but without success. Persistence, however,
is the name of our game, so, like Robert the Bruce's spider,
we try again with the May issue. Obviously you will know
whether it was "third time lucky" by the way you received this.
We are expecting some comment in "Letters to the Editor" -
is it an improvement on the old system? - does the new cut-off
time limit the usefulness of "QRM"? - what are the other pro's
and con's? Your opinions will be much appreciated.
Rroadcasts have heen the sulrject of much deep debate and new
effort lately. In last month's "QRM", you will have seen the
whole page contributed by your new Divisional Co-ordinator,
Arthur, VK7GH, Even before that issue was distributed, (in
the south, anyway), so many phone calls were being received
by your Editor, that Arthur (hoving them passed on to him)
must have wondered what he'd done to deserve all this. That's
a good sign, though. At leust it means members are taking a
renewed interest in sending news for the broadcast.. As we've
said (frequently), "we have the technology" to produce a
first-class broadcast every week. Now we must get the gear
‘together and supply it with information.Arthur's job won't
seem half so overpowering then.
The TARC ot Launceston demdstrated once again ,ust how much
organisation and effort is put into this annuul evert. As
ik
<.
visitors, we were quite unaware of any heart-stopping
disasters there may have been behind the scenes, the whole
system of accommodation, catering - and the exhibition itself -
ran so well. The variety of techniques on display was most
remarkable, even to experienced amateurs' eyes. The public
would have been even more impressed, but here was the one
disappointment - comparatively few members of the public
turned up to see this wide-ranging show ofamateur equipment.
Why this was, perhaps only local people can tell, but what a
fascinating occasion they missed!
The doyen of the south's Activity Centre, Rai, VK/VV, won the
Homebrew Competition with his QRP 80m transceiver. The other
un-named prize must go to all the Northern Branch amateurs
who did put time, effort and expertise into TARC 1986.
Yl vz oK.
Letters to the Editor.
The Editor "QRM" - re broadcasts.
As a sideline or a discussion
point on the broadcast problem, the following stats., may be
of interest:
Covering the period of 39th June 1985 to 23rd Feb. 1986, there
were 34 broadcasts, 74 different callsigns were logged and
the following filtered out:
Stations calling back 20 to 34 times: 3 (2 F 1 R)
" " " 10 to 19 times:5 (5 F)
" " " 6 to 10 times: 9 (6 F 3 R)
" h " 2 to 5 times:27 (18 F 9 K)
Once only :30 (17 F 13 R)
The frequency was 3570kHz and where stations were inaudible
at my station, the calls were logged via the relay station or
the station handling the callback,
Considering the number of amateur members in the State and
relatively few who deign to call back even once in eight
months, one begins to ponder the requirement for a broadcast,
whether a high quality microphone job or even poor quality tape.
As for the idea of starting the broadcast at 0900 EST, I
cannot see any advantage - in fact the reverse, for those who
are not awake at 0930 will certainly NOT be at 0900:.
I am sufficiently modest to admit that I am one of the two
Full call members who have called back in the top bracket.
73 from Tom VKZ7AL.
3
Letters to the Editor (continued)
(From previous page - Tom points out, in case you hadn't
already worked it out for yourselves, that "F" means Full
call and "R"™ means Restricted).
Dear Mr. Editor,
As a listener, I am able to hear all that is
said, even the comments of the knocker, and the unpleasant-
ness they create far and wide. I'm sure some don't listen to
themselves. This led me to look up the TRUE meaning of the
word "amateur",
The Webster Encyclopedic Dictionary meaning is as follows:
"Amateur: one who cultivates any art or pursuit for the
enjoyment of it, instead of professionally or for gain,
sometimes implying desultory action or crude results, a
devotee. Of or being an amateur; lacking the talent or polish
of a professional".
So, considering the true meaning, perhaps it's time the
demand to equal the ABC with broadcasts - and our friend
Murphy - were put to one side and replaced with the attitudes:
"good effort", "keep trying" - after all, to try and fail, or
to maoke a mistake is better than not to try.
A Listener (name & address supplied).
SO YOU WANT TO CONTACT THE EDITOR?
His name is John Rogers. His callsign is VK7JK. His
telephone number is 002,293402. His address is:
1, Darville Court, '
Blackman's Bay,
Hobart, 7152,
And when you lose your copy of "QRM", remember he's QTHR.
When he is at home, the 2m rig is running and listening to
Repeater 2.
WOULD ALL ASPIRING CONTRIBUTORS TO "QRM" PLEASE NOTE THAT
THE EDITOR'S CLOSING DATE FOR THE JUNE .EDITION WILL BE
15th. MAY,
o
INTRUDER WATCH REPORT, 1985-1986.
This is the Annucl Report from Tasmanian Monitors, preceded
by a comment from Bill Martin, VK2COP, Federal Intruder
Watch Co-ordinator to the Federal Executive of the W.I.A.:
"1985 has been a quiet year for the Intruder Watch. As the
solar cycle bottoms and less DX is to be found on the bands,
it follows that more amateurs would spend less time listening
around. Consequently, fewer people submitted reports than in
1984. However, the quality of the reports holds steady and it
is pleasing to see people still lending a helping hand,
although there is always room for improvement",
During the year we heard 273 intruders in VK7. Monthly totals:
Mar., Apr. May. Jun. Jul. Aug. Sep. Oct. Nov. Dec. Jan. Feb,
18 27 6 25 14 32 28 35 45 5 21 17
The National Statistics are as follow:
Total number of Intrusions reported: 7466 (7468)
Broadcast Mode: 4289 (5157)
CW Mode: 1208 (964)
RTTY Mode: 1516 (1348)
Other Modes: 453 (---)
No. of Identifications heard: 843 (727)
No. of Contributing Observers: 51 (98)
No. of Log Sheets submitted: 543 (621)
Overall VK4 led the field with 330 logs, followed by VK2 with
98 logs. VK4 had 15 observers whilst VK2 had 12. Tasmania
supplied 20 logs from 3 observers, which was more than VK6,
VK8 and VK1 combined,
We have had some success in getting some Intruders to QSY
permanently this year. For example, a French Rlynesian PTP
link down on 7003 kHz was shifted after complaints from IW
throughout the Pacific. The "Voice of Greece" in Athens,
which fired up on 7095kHz to Australia at 2000UTC, was
shifted to another frequency after numerous complaints from
amateurs and various administrations in Europe and other
areas, after only a few weeks of scheduled broadcasting on
that channel. The ABC and Telecom cleaned up harmonics from
5AN in Adelaide on 3564 after numerous complaints.
The IW was responsible for the American FCC opening a case
against a Maritime Mobile Station passing commercial-type
traffic on AMTOR on amateur frequencies and utilizing two
American ham stations. The vessel was subsequently blown up
5.
in Auckland Harbour by French secret service agents, in a
complete u a
ly nrelated ctivity.
The amount of Intruder activity has not diminished, despite
the reduction in the number of logs. With the sunspot minima,
many more intruders are encroaching into our exclusive alloc-
ations. We have to be vigilant and continue to log these
stations. The recent appointment of Bill Martin, VK2COP, as
IARU Region Three IW Co-ordinator with direct access to the
International Frequency Registration Board (IFRB) in Geneva
should assist and improve the effectiveness of the Intruder
Watch in 1986,
I would like to thank Mr. Gerry Visser VK/DQ for his assist-
ance and continuing co-operation throughout, 1985 and I
sincerely hope that other VK7 stations will also contribute
to the IW in 1986.
Robin L. Harwood, VK7RH.
TECHNICAL BULLETIN SUBJECT: £L6E
Finals:61468vs S$2001(or8298A)
From time to.time, uninformed comment suggests that there are
marked differences between the Japanese S2001 tube and the more
commonly known 61468B.
To put the matter to rest, we have consulted Japanese tube
manuals and found that the characteristics of both tube types
are discussed in the same breath. With the exception of
filament current, (the S2001 draws 1 amp and the 6146B 1,125
amps) voltage ratings and power outputs are identical -
repeat, identical. A photocopy of the Japanese tube manual
is available for the unbelievers!
Compare the following CW ratings for the S2001 with the 61468
(per ARRL Handbook):
Ep(V) Esg(V) Ecg(V) Ip(mA) Isg(mA) Rcg(mA) Po(W) Pcg(W)
750 200 =77 160 10 29K 85 0.3
Note: Rcg is grid leak resistor for Class C operation.
Information sent in by VK7AN Allen.
et ettt ee e e e
SJOERD GOES SOUTH (see last month's "QRM")
VK7ZSJ will be -operating-on Macquarie Island as VK@SJ on
Mondays and Fridays at 09.30Z. Frequency: 7.085 MHz +.
I
C.
ADVERTISEME
NTS.
BYRON, VK7BD is anxiously looking for o VK3 FM Carphone.
(He says it used to be called an IGL). Anyway it's
a 2m FM transceiver. Byron is QTHR.
KEVEN, VK7KY requires a TH3 antenna for his Possum Bay site.
If you have one to sell, Keven is also QTHR.
MIKE, VK7ZMHoffers for sale one FNB4 Nicad pack to suit FT209
or FT209RH or FT709. Price on application. Tel: 722693
or 2/8 Chapel Street, Glenorchy.
FOR SALE: VK7RM has IRC's for sale ot 50 cents each (minimum
of 10). Include SASE with order. QTHR or 002,232808.
“TAS DEVIL" 80m CW QRP Tronsceiver: PRINTED CIRCUIT BOARDS
for sole. V.F.0.Control! Voriaoble break-in speed!
Side Tone! CW Filter! Rx mute! Net Switch! Electronic
Switching! Price: $16.00. Also available - Component overlay,
circuit diagram, parts list. Proceeds to Southern Branch
Activity Centre. Contact Rai, VK7VV QTHR or 002,727743,
WANTED: Circuit diagram for PYE VICTOR VHF Transceiver,
type MVF 529. Tim Show, Tel. (work) 002,389235 or
(home) 002.439832.
To: Broadcast Co-ordinator VK7GH
34 Ashbolt Crescent, Lutana 7009
I wish to have the enclosed advertisement published on the Divisional
Broadcast on Sunday . « . . . . . at 2 a.m.
I certify that the advertisement refers to a bona fide amateur
transaction, and is not concerned in any way with commercial business.
Signed . . ¢ ¢ ¢ ¢ 4 v e e e e e e Call Sign « v o v & o « « o o
1»
VK7''1 Sunday Brocdcasts.
It has been coreed that the Sund~v morning brocdcasts
will commence ot N09.00 instead of 09.20 locol time as from
the first Sundcv. in Mcov.
Itclian Rodio “Amoteur CLEE'
Gerry, VK7DQ gives us details of the Italian Radio
Amateur Club which opened its doors to overseas amateurs
recently, You would need to send 3 IRC's to:
Mario Ambrosi,
Via Stradella 13, 20129,
Milano, Italy.
For this you gain access to: QSL Manager Manual, 40
different computer programmes (Commodore 64), Italian
stamps, DX infor net, DX Club Award.
Further details, addresses, etc., are available from
Gary, VK7DQ, QTHR.
B RANCH NOTTICES
NORTHERN BRANCH MEETS AT 8 P.M. ON THE SECOND FRIDAY of
each month (etcept January) in Room G25,
Swanson Building, Australian Maritime College, Newnham,
Launceston. (Address: P.0.Box 275, Launceston, 7250).
NORTHWESTERN BRANCH MEETS AT 8 P,M. ON THE SECOND TUESDAY of
each month at the Penguin High School.
(Address: P _0.Box 194, Penguin, 7316).
SOUTHERN BRANCH MEETS AT 8.15 P.,M. ON THE FIRST WEDNESDAY of
the month, at the Elizabeth Matriculation
College, corner of Warwick and Elizabeth Streets, Hobart,
until further notice. (Address: P.0.Box 123, Sandy Bay, 7005.
Broadcast Officers.
Divisional Co-ordinator: Arthur VK7GH, 34, Ashbolt Crescent,
Lutana, 7009,
‘Tel: (H) 002.284963 (B) 002.305600.
Northern Branch Officer: VK/AV Bill.
Northwest Branch Officer: VK7ZFH Frank,
Southern Branch Officer: VK7GH Arthur.
¢
The Minister says it forms DOC Minister Duffy reaf-
DOC news part of the Government's plan firmed the figure of $490 million
to bring more commercial televi- as the estimated value of the
A report commissioned ear- sion services to regional Aus- cross-subsidisation from profit
lier this year by the Department tralia. making services to loss making
of Communications has warned In the specific case of WIN-4,
services in Telecom in 1984-85, a
against selling off profitable the move to UHF had to be matter vitally affecting country
aspects of the operations of Tele- made because the station, by its people.
com and OTC. It also says Aus- presence on VHF channel 4, was
tralia should reject any pro- blocking further development of Work on installing new earth
posals from private international FM radio services in the region. stations in remote communities
satellite companies for direct ac- Two new proposed local com- to tap into Aussat television
cess to Australian users. mercial services will transmit on transmissions is gathering L
Australia should also look at the VHF band along with SBS momentum the DOC Minister
ways in which its Aussat satellite and part of the ABC service. has noted. Special decoders
system could provide coverage being used in the program are
The ABC will move totally to under manufacture in Toronto,
to the South-west Pacific and UHF, making Wollongong a
South-east Asian regions, the Canada, and will be tested at the
UHF-only city.
report says. DOC'’s lab in Canberra before
A Department of Communica- being despatched to the outback
These and other recommen-
tions spokesman has appealed to sites. In all, 61 new earth sta-
dations are contained in a report
farmers across Australia to en- tions are to be installed.
entitled Transborder Data Flow
sure all their two-way radio
and International Trade in Elec- The Government has decided
equipment is licensed so that any
tronic Information Services: an to waive sales tax on earth sta-
threat of interference to other
Australian Perspective, by Dr tions for domestic use bought to
John Langdale, a senior lecturer services is averted.
The spokesman warned that receive satellite radio and televi-
in geography at Macquarie Uni- sion services from Aussat. The
under the Radiocommunications
versity.
Act 1983 penalties for unli- Minister has predicted the bene-
Mr Michael Duffy has an-
censed use of radio equipment fit to country people should be
nounced that the Government at least $500.
has taken the first step towards include confiscation of equip-
ment and a fine of up to $2000, The cost of each station, as al-
achieving the equalisation and ready indicated by distributors,
or imprisonment for a maximum
aggregation of regional commer- ranges from $2250 (excluding
of twelve months.
cial television by agreeing in A prominent National Party sales tax) for a 1.5 metre diame-
principle to the upgrading of spokesman has described claims ter dish. Exact prices would be
facilities at many of the Com- that a coalition Government subject to usual market place
monwealth's multi-purpose would sell Teietom as ‘“‘alarmist negotiations between seller and
transmitting stations in regional buyer.
and untrue”. Mr Bruce Lloyd,
areas of Australia— an essential spoke of Telecom as ‘‘the key
step if its broadcasting objec-
tives were to be met.
safeguard for country people. (Excerpt from ET| for
The Illawarra
This puts Mr Lloyd squarely March 1986 with
television at odds with Opposition Leader
- operator, WIN-4, has been in- acknowledgements and
John Howard, and the Opposi-
formed that it would be required tion spokesman on Treasury thanks)
.
to move to the UHF band within matters. Mr Jimn Cariton.
three years.
THE 722 JD TRI-BAND YAGI BEAM.
(From Noel, VK7EG ex Z21 AG) Onthe next two pages you will
find details of o 3-element tri-
band yagi for 10, 15 and 20 metres. Originally this project
was presented to the Zimbabwe Amateur Radio Society by John
Stoole, for the developer Ralph Ward 722 JD. It appeared in
their magazine QUA, but I have only the diagram. Several of
the beams were made in Zimbabwe and proved very successful,
Ralph Ward is described as the developer because the antenna
bears a distinct resemblance to the Mosley TA33 Junior, but
with some slight differences. It is also cheaper and has the
satisfaction of "home-brew"!
(The Editor's thanks to Noel and acknowledgments to QUA for
this article).
5
_CONSTRUCTION NOTES FOR Z22 JD TRI BAND YAGI BEAM
The diagram contains all the essential details for the construction of a good
3 element tri band beam for 10m, 15m, and 20m, It is fairly cheap to make and all
materials should be easily available., Access to a lathe or a friendly lathe
operator is a help,
Dimensions as given in the diagram have proved to work well and should be adhered
to, at least umtil you think you know more than the developer! In particular the
trap dimensions should be followed carefully.
w
These notes supplement the diagram and it is hoped will be of help, Have fun!!
EIEMENTS
Reflector and Driven elements consist of 25mm o/d tubing for the centre 3m or so,
reducing down in stages to fit the trap tubes., The length of each different
diameter is not important, but do allow a generous overlap at the end of the 25mm
sections, This permits adjustment for tuning later if neccesary,
Director starts with 22mm ali, tube and reduces in the same way,.
If the tubes are a close sliding fit at‘each joint self tapping screws may be
used, otherwise the outer tube will need to be slotted for 25mm or so and a hose
clip used together with a screw.
Tubing is available from Comalco in launceston who will supply a catalogue of
their products, BUT before getting all excited at all the beauwtiful sizes listed,
you should note they can only supply those sizes printed in heavy type.
TRAPS
The coil formers are made from almost any "RF proof" plastic, Test your plastic
in a microwave oven by heating for 3min, If it does not heat up you are in
business. '
The formers are most easily made by screw cutting a 10 TPI thread en the 25mm
diameter first, this is where the lathe comes in, End pieces are then cut to
fit the inside diameter of the trap tube and glued on to the threaded section,
The traps should "dip out™ at the frequencies given in Fig 1 and this can be
checked with a dip oscillator before the element sections are fitted to the traps.
The traps should be completely assembled before checking, that is both coils
should be in position in the trap.
Tuning should be done by altering the length between traps for 10m and for 20m
the end sections can be adjusted. Note that 15m cannot be adjusted individually,
you will have to arrive at a comprise between 10m and 15m,
Also distance between elements can be varied if you feel really bravelll
Note; the March'1986 Amateur Radio contains an article on the TA33 beam. This is
almost identical to our beam and the suggested gamma matches do allow you to
adjust each band independéntly, however try the beam first in its original form,
The comment.. on cleaning and greasing is well worth reading and following.
Remember, the breather holes in the trap tubes MUST face downwards for drainage.
COAX CONNECTION
Note that the diagram shows the coax connected directly to the driven elements
and that Fig 4 states that a balun may be used., Those of you who are familiar
with the Mosley' TA33 Jnr beam will know that Mosley have the "earthy" element
gtrapped directly to the boom, This can be tried if TVI is a problem, or a balun,
or a 150mm, 10 turn coil of coax can be tried., This coil is said to reduce TVI
while producing a more symmetrical lobe pattern than with one element earthed.
Once again have fun and enjoy being able to say on air, ' home brew yagi old man',
. \O
3 ELEMENT TRI BAND YAGI FOR 10m, 15m, 20m.
DEVELOFED BY RALPH WARD Z22JD
INNER SECTIONS OF ELEMENTS START AT 25mm
@
TUBE TAPERED CONVENIENTLY DOWNTO 13mm §
(All frequencies shown are in Mhz) AT TRAPS
202 21,7 27202 22y "5+—~f~filf-9£—+§iffi+
(377) (23RT) Reflector (23%T11(371) Reflector
213 286 28,6 213 k] 2-94,
6T 3T Driven Element
136734230 (23T) (367)
223 259 299 223
(33%7)(217) Director (217 (33%T) Director
Fig.1 SCHEMATIC PRESENTATION ot Fig2 PHYSICAL DIMENSIONS
ote: T
Dimensions are for CW, Add 10,5" to centre
not to scale section for phone.
t W@OUTER TUBE 13%°
SLOT FILED IN COIL FORMER @ TUBE
13mm 10 TURNS PER INCH
TO ALLGW WIRE [0 PASS Tormingte wig - 1O M@, THRED FUSE
—~ THROUGH . under sCrew
BREATHER HOLES L0 ~ 13 mm
o
ON UNDERSIDE OF }g%fil SE};%NK
TRAP
Fig3 DETAIL
OFTRAP
not_to scale
STANDOFF
20mm PVINSULATORS
POD ) . BA#EJEIE
1:1 . MAY BE INSERTED 5‘“&%%83
ORIVEH ELEMCNT INTO STAND-
z FF INSULATORS
FEEDER (SOn COAX)
_ALL HARDWAR
15CADMUMPLATED
E
Fig & DETAILAT ORIVENELEMENT Dotto scale