QRM
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AMATEUR
t BI &<= RADIO
Bulletin issued by the North, North West and
Southern Branches of the Wireless Institute
of Australia, Tasmanian Division.
Registered for Posting P.O. BOX 275
as a Publication, LAUNCF.STON
Category B. TAS. - 7250
JULY 1979 price 4Ot
VOL. 9 NO. 4
M E E T I N G S
4 July Southern Branch - SES Rooms Melville Street, 8.00 p.m-
13 July Northern Branch - Clubrooms 34 Bourke Street, 7.45 pm.
10 July North West Branch - Penguin High School 7.30 p.m.
C O N T E N T S
2 Southern Notes 10 Nicholson File Guide
3 Northern Notes 11 New Stations
JD Electronics (Ad) Battery Charger
4 Weller Soldering Guide 12 State News
5 Advance Electronics (Ad) QSL Bureau Notes
6 LM380 Circuits '13 QSL'ing
7 Home Colour Film 14 North West Notes
8 Gelston Communications (Ad) 15 Letter to Editor
VHF Notes 16 VK Electronics (Ad)
9 A Technological Survey
ATHOL JOHNSON MEMORIAL V. H.F. CON'I'EST
FERPUAT TROPHY
Tasmanian Division
ATHOL JOHNSON MEMORIAL V.H.F CONTEST
PERPETUAL TROPHY
2 QRM
SCRATCHINGS FROM THE SOUTHERN SCRIBE
The main topic of this month's notes is of course the square dance
to be held on Saturday the 7th of July at the Wentworth Special
School Bellerive. .A.G.S. members have worked very hard to put on
this and previous functions, profits from which all go to boost the
Southern Building Fund. Tickets are available from any w.A.G.S.
member (Northerners or North-Westerners would be very welcome if they
feel like making a weekend of it). Unfortunately, it is being left
to the same old few to provide support and patronage for these
functions.
It has been said before, that people in this world are made up of
four classes of bones - the wishbones who wish it were all done
with no effort or help by them; the jawbones who talk alot but dent
do anything; the knuckle bones who knock every effort made by others;
and the backbones who do the job. After last month's QRM there
would seem to be an over abundance of knuckle bones in the North as
stinct from our problem in the South of having ..:'ar too many
shbones.
The last w.A.G.S. function was only a success because the organisers
so turned up and supported the actual function. le hope that the
square dance will be an opportunity for not so active members to
ome along and have a good social night and swell the numbers.
next W.A.G.S. meeting will be held on the 16th of July at the
of Sue VK 7 ZSU. All w.A.G.S. members and other IL's who are
erested are welcome to attend. Following the Square Dance, on
wth of August there will be a bingo night at the QTE of
Dorothy and Greg Noble - look for more information in next month's
QRM.
Appropos the information to the broadcast on Sundays, we noticed
that recently, Joe VK 7 BJ was taking no chances when he commenced
saying " ladies and other amateurs ------", This latest in a
series of skirmishes between VK 7 HD and several OM's (not includ-
ing VK 7 NPR her OM) acknowledges at long last, the status of lady
amateurs and the fact that they do not belong in the general label
of "chaps". THE SOUTHERN BRANCH NOW HAS ITS OWN CALL SIGN VK 7 SB
which will be used when appropriate.
Not all Southern Branch members are wishbones - heard recently of
two amateurs (VK 7 GD and VK 7 PA) who were so eager to attend the
Southern Branch executive meeting and to make sure they were not-
late, they turned up a whole week early. The Southern Repeater is
ill performing well. Recently it was off the air for a matter of
hors only, due to a faulty relay and this is the firs: time it
has been off the air since Christmas. Recently, it was worked by
a VK 5 amateur and we believe that Tony VK 7 ZTA had a number of
simplex contacts on two metres with VK 5 on the same night. Thats
all for this month,
73 and 88 Sue VK 7 ZSU
7OR SALE
AESU YC 355D 200hz counter, as new - $180 YAESU RG? Receiver -
Condition $250 BIRD Thruline wattmeter Model 43 fitted with
10-25-50w Modules for 200-500Mhz $65 AWA Voltohmyst; Model
2A56074 with RF and Standard Probe $55 Make cheques payable to
Richardson - purchaser to pay freight - all in usual VK 7 NR
good condition.
73 de VK 7 NR/ A.N. Richardson
c/o RMB 1215 DUNOLLY Vic 3472
Norm is re-arranging his gear to suit the caravan and wants the
amateurs here to have first go for the above gear. If your inter-
ested contact Norm direct)
JULY 1979 QRM 3
NORTHERN BRANCH NOTES
The monthly meeting was held with 20 odd members present. (the odd
refers to numbers only) The main points of the evening were the
following motions being put and carried. The N.B. make a decision
on the purchase of a HF Transceiver in the order of $500 at the
meeting 13 July 1979 - This Branch purchase a VHF Transceiver
or Transceivers for Club use and the proposal be confirmed or
rejected at the next meeting 13 July 1979. In regards to these
two motions the Secretary will contact QRM Advertisers and ask
them to submit tenders to supply HF and VHF Transceivers. Members
who have surplus equipment may also tender to supply. No tender
will necessarily be accepted but the decision of acceptance will/
be that of the members. The other main motion put and carried was
that lectures be restricted to meeting nights except for exceptions
such as outside lectures. Ken Kirkman was nominated andaccepted
as QRM Editor. Reg Emmett VK 7 KK, Ian Clements VK 7 IC, Les
Harper VK 7 NHA and Ken Kirkman volunteered to form a committee
to ·handle TARC. Your support is asked for and is vital to make it
a success. A WICEN exercise to assist the Light Car Club will be
held on Sunday 10th of June and if it comes off like the last one
it will be a success. Activity nights will be restricted to
Monday nights from 8p.m. onwards - this is after CW classes which
run from 7 to 8p.m. By the time you receive this QRM Cw speeds
will be 5wpm. and higher. Joe VK 7 JG donated some test gear
and Ed VK 7 HE donated a GDO to the Branch for use by the members
at the Club Rooms. Robert Harper was proposed for Associate
Membership and accepted.(I reported last month that Robert passed
his novice - he actually has'nt received his results as yet but
lets hope our first report will be right). Dont forget we are
endeavouring to have a trade table at monthly meetings nights - so
support it BRING SOMETHING.
STOP PRESS 73 de VK 7 HE
Proposed date T.A.R.C, '79 17-18 November
Alanvale College
J.D. ELECTRONICS
64 Wentworth Street,
NEWSTEAD
Suppliers of Yaesu Amateur equipment, Test Gear and all
Accessories. Antennae and Fittings. Novices check
us now for a really good deal.
# -- @RM JULY 1979
ELLE RSOLDERING GUIDE
Soldering Tools Materials
Basically there are two types of Solder
electrical soldering equipment; Solder is an alloy of two or more
one. the soldering iron and two, the metals which is used to join metals
instant heat soldering gun. Today's together by the application of heat.
soldering irons are nearly all of The heat is applied to melt the
pencil type construction and range solder, but not the base metal.
in output irom 15 to 250 watts. Ideally a solder should have the
following qualities tor the best
performance:
Wetting
It should flow over the metal,
bonding or alloying with its surface
at every point, including the
crevices between wires and
terminals
Temperature
When selecting an iron ensure It should reach liquid state and
that it is safe. that the tips will not wet the metal at a low temperature
2ec0me loose or freeze in position.
that the tip can be easily changed. Strength
Also make sure that you buy good As hard as possible but must
soldering tips. Make sure that you be free of brittleness.
choose the right tip and iron for the
ype of work.
A 100 watt iron with a
3"/9·5mm diameter tip and chisel
shaped is ideal for larger electrical
--a
$ Wetting- mentioned above-
is the action between the solder and
the base metal being soldered.
Wetting provides the bond between
the metals being joined. It should
work. A 40 watt and under rating not be confused with tinning. which
with a Ve"3mm or 3e"/5mm means pre-casting.
jiameter tip is suitable for light Rosin-core solders are
electronic connections. available in smal I packs for the
Also on the market are cordless home user. The smaller sizes permit
soldering irons. These have better control of the connections.
batteries which enable joints to be such as on printed-circuit boards.
nade without being connected to a Many solders have a
power outlet. To recharge the continuous inner core or cores.
batteries the iron is connected to a The flux cores vary tor application.
power outlet via a transformer. Flux in a core is automatically
A cordless soldering iron imparts metered out correctly. Solder is also
greater freedom to soldering and is available without the inner flux core,
ideal for in-the-field applications. for use with liquid flux. •• •
Corrosion on a tip is an
insulation and will prevent the Flux
proper transfer of heat from iron to Oxides form on many metals in
the connection. A well tinned tip will a matter of moments and flux is
give good heat transfer. Tinning is used toclearthem as they affect the
the coating of the tip with solder. connection. These tarnishes
During the soldering process it is become soluble in flux, and
possible for solder to build-up on evaporate when the flux is heated to
the tip. This should be regularly boiling point.
wiped off on a wet cellulose There are two basic group of
sponge. An iron or nickel plated tip organic and inorganic.
should never be filed to remove organic fluxes are used in
solder or corrosion. electrical soldering, whilst
inorganic fluxes are used tor
sheet-metal work and plumbing.
The Soldering Gun Most organic fluxes are
non-corrosive, and inorganic fluxes.
The instant heat soldering gun
a!ihough much more active than
will projde the user with heat in
organic types, are corrosive to
less thah 10 seconds, at the press of
various degrees.
a trigger This availability of instant
heat is important to the home Organic Rosin or Resin
handyman as it imparts Resin is a general term for an
considerable safety for around the organic solid or liquid, insoluble in
home jobs. Heat is only available at water. Rosin is the resin distilled out
the tip whilst the trigger is of the turpentine of white pine and
depressed The tip permits provides a good non-corrosive and
soldering in tight places and a bulb non-conductive flux. Prior cleaning
illuminates the workpiece. of electrical components is
Other gun tips enable cutting generally not necessary when using
through thermoplastic floor tiles and a cored solder containing an active
polystyrene ceiling tiles, joining rosin flux.
broken thermoplastic toys and Non-rosin organic fluxes have
utensils, heat-sealing plastic bags
generally a greater soldering
and repairing flexible thermoplastic activity than rosin based fluxes, but
items such as swimming pools. they are slightly corrosive to the
base metal. Prior cleaning of
workpiece is recommended.
Inorganic fluxes are forms of
Kind Permissi acids or salts. These are highly
the COOPER active but are corrosive, and not
suited to electrical connections.
GROUP The activity of these fluxes is so high
ITED that heavy pieces of metal can be
soldered.
While fluxes remove thin tarnish
will not remove greasy or oily
or the results of the oils
of human perspiration
JULY 1979 -QRM 5
ADA ELECfllOIIICJ
SA THE QUADRANT, LAUNCESTON, TASMANIAN, 7250 - P.O. BOX 328 - PHONE: 31 7075
Ts-70Osr
I • ,:;,·/.'}>~/_,
• • ·' .. i· . . /,:
SPECIFICATIONS
• Frequency Range: 144.0 to 148.0 MHz e Mode: $SB (USB, LSB), CW,
AM, FM • Antenna Impedance: 50 ohms • Frequency Stability: Within
±3 kHz during one hour after one minute of warm-up, and within 150 Hz
during any 30 minute period thereafter • Power Consumption: Transmit:
98 Watts (120/220V AC), 4.0A (13.8V DC), Receive (no signal): 48 Watts
(120/220V AC) 1.2A (13.SV DC) • RF Output Power: SSS, FM, CW;
10 Watts, AM; 3 Watts, FM (Low); Approx. 1 Watt e Modulation: SSB;
Balanced modulation, FM; Variable reactance frequency shift; AM; Low
power modulation 4 Maximum Frequency Deviation(FM): ±5 kHz e Carri-
er Suppression: Better than 40 dB • Sideband Suppression: Better than
40 dB • Spurious Radiation: Better than -60 dB • Microphone: Low
impedance microphone (500 ohms) • AF Response: 400 to 2,600 Hz
• Repeater Frequency Shift: 600 kHz • Sensitivity: $SB and CW; 0.25 v
for 10 dB (S+N)/N, AM; 1.0V for 10 dB (S+N)/N, FM; 0.4 µV for 20 dB
noise quieting, 1.0 uV for 30 0 (S+N)/N • Selectivity: SSB, CW and AM;
2.4 kHz/-6 dB, 4.8 kHz/-60 dB, FM: 12 kHz/-6 dB, 24 kHz/-60 dB
• Image Ratio: Better than 70 dB • IF Rejection: Better than 70 dB
• Squelch Sensitivity: 0.25 µV • AF Output Power: 2 Watts/8 ohms load,
with less than 10% distortion • AM Output Impedance: 8 ohms e Dimen-
sions: 278 (10-7/8)W x 124 (4-7/8)H x 370 (12-5/8)D mm (inch)
The TS-700SP is the all-mode solid state transceiver that provides you with • Weight: 11 kg (24.4 lbs)
versatility plus over the entire 2 meter band. It's feature-packed design VFO-700S SPECIFICATION
puts you on SSB, FM, CW, and AM. The AC and DC power supplies are • Frequency Range: 8.2-9.2 MHz • Frequency Stability: Within 150 Hz
built in which allows you to operate the TS-700SP just about anywhere. during 30 minute period after warm-up • Dimensions: 160 (6-5/16)w x
Equipped with a VFO that enables continuous tuning from 144-148 MHz, 123 (4-3/4)H x 200 (7-7/8)D mm (inch) • Weight 2.4 kg (5.3 lbs)
the TS- 700SP comes complete with built-in digital frequency readout, • Model name and specifications mav change according to destination.
receiver preamplifier, VOX, sidetone, and microphone.
TH-760O &ah
ONE ONLY AT T.RIS CLEARING PRICJE
WAS $:935 NOW $835 THAT IS RIGHT
A SAVING OF $100.00
TR-7500
,,.......__
.., new TR-7600 (TR-7625) is a high-performance 2m FM transceiver
with memory, designed to permit multichannel (800 channeli operation.
Featuring the ability of repeater operation, this transceiver brings you all
the convenience aqd versatility in both mobile and fixed station operation.
The TR-760O (TR-7625) has provision for connection of the optional AC Power
microprocessor control unit, RM-76 for added versatility. supply y
PS-6
TR-7600 (TR-7625) SPECIFICATIONS
e Frequency Range: 144.0 to 147.995 MHz o Mode: FM e Frequency
Synthesizer: Digital control of phase locked VCO • Synthesizer Stability:
Less than ±750 Hz at 25°C • No. of Channel: 800 • Operating Tempera·
ture: -20 to +50°C • PowerVoltage: 11.5V DC to 16.0V DC(13.8V DC
standard) e Grounding: Negative e Antenna impedance: 502 s DC Cur-
rent: Less than 0.5A in receive with no input signai, Less than 346)4 in HI
TH7500 WE HAVE TWO OFTHESE UNITS
AGAIN OE OILY THIS IN STOCK TO CLEAR AT ONLY $250. 00
NOW SAVE ATOLT $375 AS $290SAVE $40
WE ARE PREPARED TO TALK DOLLARS ON ANY OF THESE UNITS SO FOR ANY ENQUIRIES
FEEL FR.EE TO CONTACT: E:ITHER RICK BECKER OR ROGER WOOLLEY
BE ARRANGED
6 QRM JULY 1979
LM380 CIRCUITS
+ 12-22V Minimum parts audio amp.
If power supply filter
capacitor more than 2" from
IC use decoupling shown at
pin 14. Parasittic supp-
470 ressor (2.7.n. .1uf) some-
time needed.
,
l-·- L,Kl
_!_ •.,
--,-
I
-: -: -. -=- -
'
Do
Single to dual supply splitter.
0/P current limit .:::1.3A. Voltage
balance 2% per 100ma unbalance
load change.
+
Audio Amp with boosted
voltage gain. Normal gain
x 50, boosted x 200.
RL
®
from the National Semiconductor Linear Applications Handbook.
73 de VK 7
JULY 1979 QRM 7
HOME COLOUR FILM _ PRINT PROCESSING
I cut my 10 x 8 sheets into four sheets using a guillotine and in
darkness with only the safelight; as previously mentioned. If you
don't have a guillotine then you can use a pointed sharp knife and a
ruler but it is a bit more difficult - no doubt you will devise some
method to suit your own requirements. Suitable guillotines can be
bought for about $17. Place your cut papers, all the same side up,
in a dark-proof bag for ready access when printing. I keep the dark
plastic bags that the paper comes packed in, but until you have used
up your first batch of paper you wont have any so use a box with a
cover or something similar. Before going into the actual printing
procedure the following comments may be useful.
The biggest and main problem is determing which filters and how many
to put into the filter drawer of the enlarger. The first print or
two will never be right and some adjustment of filtration is required.
There will always be an overall colour cast to the print and the
object of the exercise is to remove this colour cast. It may be
magenta (reddish brown), yellow, blue, green, any colour but it will be
an overall colour. Look for the areas in the print which should be
white and see what colour it actually is. Initially for your test
print use a negative that has a lot of different colours in it.
There is one rule: if the colour is in the print then pur it in the
filter drawer. This means that if the overall cast of the test print
is, say, yellow - then add a yello•,1 filter to those already in the
drawer. If too much yellow is added the cast will go blue, which
means that you have gone too much and reversed the colour, you have
over-corrected so reduce the amount of yellow and do another test
print. Its not easy when you start and you will waste a few papers
but; persist with it, it will come_yith_practice.
Although you get three lots of colour filter with the filter set,
Magenta, Cyan and Yellow, in nearly all cases it is only necessary
'to use Magenta and Yellow in your filter drawer. Almost all combin-
ations of colour can be obtained using Magenta and Yellow, either by
addition or subtraction of one or both.
ALWAYS USE AN ULTRA VIOLET FILTER IN THE ENLARGER DRAWER AT ALL TIMES.
(these are supplied with your filter set.)
As a general guide use: 05 size filter for a slight change in colour.
10 size filter for a medium change in colour.
20 size filter for a large change in colour.
If you want to remove yellow from the print put in yellow filtration.
Same applies for magenta. If there is too much blue in the print then
you have over-compensated by having too much yellow in the drawer -
take some yellow out. If too much green then take out some magenta.
If too much red try adding some magenta and yellow to the drawer.
Remember, the filters are designed primarily to filter out their own
colour from getting to the print. If there is too much of one
colour in the drawer it will reverse the process. E.G. too much
magenta will make the print go green, too much yellow will turn it
blue and so on. Its difficult to describe but practice will show
you the score
(this article by Peter Harrison, VK 2 NPM - cont'd)
FOR SALE
Belcom Liner 10 28.480 to 28.710 VXO cont coverage - new $210 Shure
401A hand mic - new $32 Antenna coupler HC25O 300 PEP - new $76
ICOM50L Linear Amp suit IC502 - new POA
VK 7 NAB 7914
8 QRM JULY 1979
3
COMMUNICATION
TWO WAY RADIO SALES & SERVICE
YOUR LOCAL 40 LAVENDER GROVE
PLEiSEY A
ea PO Box 1311
le&er6nie
VICOM
ontact us for your next purchase.
AGENT
Phone4 4 3 8 8 2
LAUNCESTON 7250
TAS
0PEClAL.
IC22 100k only 299.00
Also available
1070I 1380.00 hatching Power supply 253.0
..2211 799.00
aircraft Receiver I6 channels can or manual AC/DC operation
- crystals supplied 199.00
Output Valves 6JS6 only 18.00 per pair.
quality Pre-owned equipment.
..C202 2etres hand held SB.Transceiver fitted with two additional
crystals. Still operating with origional batteries only ,3195.00
HEAI1EK1T DLS'I'RIBUTER
CAN1'ENNA One of the most useful station accessories. Provides 50 ohm
}on Inductive load with SR less than I.5: I up to 300 Lhz. 40.50
i,i Directional ·.vattmet er covers 100 Mhz to I Ghz. Three fordward
ranges 30-75-300 Jatts. A must for the serious operator 246.00
Coax Switch 4 position with aerial earthing provision. 24.50
-----·-------------------------
lsed Daiwa 140-500 Direct Reading ;:;·:tR/2power Tiet er $95.00
V.±.. Dotes.
ta lot has been happening over the past month,witt only two DX
cbenings for the month. One on two metres to VK5 and VK3 at the same
time Repeaters up to VKI being worked. The other on 6 metres on the
15/6/79 when the band opened to Sydney area and then swung around to
.sdelaide. Stations 1:'Iorked included VK2 's BA CA UQ VKAK local
stations active were VK7's DA LZ T JG You will notice that all the
stations operating were full calls. ix metres requires a lot of
attention this time of the year to catch the brief but good openings.
I was running 3 watts and received 5/9 reportE from the Sydney
stations. VK2ZHE is active on Lord Howe lsland this is a separate
country so look for Henry he will be there for another week or so.
432~hz Activity is on the increase with bigger and better aerials
being erected but once again it is mainly confined to the 3 active
VF stations in Launceston.
Kevin VK7ZAH has a 88 element Jaybeam
Ianiel VK7DA Home brew stacked I6 element IL. deseign
Joe VK7JG 4S element Jaybeam
All we require now is a good opening to put the equipment to use.
Ihat is all for this month.
73
Joe VK7JG.
FOR SALE
Teletype tape perforator and tape reader $35
VK 7 JG
QRM 9
A CC'ECENOLOGICAL SURVEY OF BROAD-
SC_ING'S PR-IS@QR 1876-1920
Al-hough the aerial conduction scheme passed into obscurity, systems
involving conduction through the ground appea:red over the next few
decades and have been revived in modern times. hese, however, were
via~le systems without any question, though only over limited dist-
ances. So far as our broadcasting story is concerned, however, ground
conduction becomes intertwined with certain other related phenomena in
the developing telephone technology. 'We mentioned earlier the exper-
imntal telephone "concerts" promoted soon after the instrument was
inroduced in 1877, a telephone "broadcast11 was made from New York to
Sarasota Springs, New York, using a newly developed Edison Transmitte~
'.I'hc musically programming was heard accidentl.y L-1 both l"rovidence and
aos~on due to electrical leakages between adjacent sets of wires on
trunk lines north of New York City. Although conduction leakage
th:.:'ough the ground was the principal cause, induction through the air
was involved. Within both phenomena lay mechanisms for a new mode of
communication: suppose one were to purposely cause induction of energy
with large loops of wire, or conduction with stakes buried in the
ground - would not a useful communication device result? This line of
development appealed to several late 19th century personalties. though
co:.:.siderable thought toward wireless techniques of this general type
was in evidence even prior to 1350. The crucial point to remember,
hoverer, is that te scientific base for inducvion - conduction comm-
un.cation was a natural outgrowth of conventional telegraph and tele-
ph(,ne technology, and was not directly related to t;he Hertz-Marconi
a.poach to wireless. 'The latter method employed radiated waves of
hi.b"."; frequency which had the capability some distance. However, there
a.re certain interrelationships between these various systems which
we will describe in the following critical review of the work of one
ea'lg; "wireless broadcaster."
Na:;han !Stubblefield
al
Na,;han 3 .. Stubblefield (1860-1928), or Murray, Kentucky, was a self-
ta~ght tinkerer-experimenter. He is more in the tradition of Daniel
Drm4baugh than Edison or ant of the university savanGs However, he
a persistent vision of the success of hit:; method of communication
aJ'.K. influenced several businessmen to finance commercial exploitation.
:::is first claim to fame, however, came via local "acoustic telephone"
hookups in Murray circa 1890. Following invt::stigations into induction
and. conduction telephony, he developed sveral types of apparatus and
pe:,:f"ormed some public demonstrations prior to 1900. In March 1902
he 'Succeeded in transmitting speech from a boa~ in the Potomac River
to shore-based receivers. Inspired by this opeat;ion he boasted of
the praccicabillity of sending simultaneous messages from a "central
distributing station" and of conveying "general tra:;..'lsmission of news."
Houever, commercial thoughts were directed toward point-to-point comm-
uriaion. The Wireless Telephone Company of America was formed and
a. ctive stock promotion plan put into ope:cat:i.on,, Although the stock
pras~ectus was quick to point out the virtues of a cheap wireless
s7em versus the expensive Bell Telephone lines, the fact of the
,-r1a·..;·:;er was that induction/conduction telephony was too marginal in
ance capability to offer any serious compet:i-tion to Bell. The
Telephone Company of Charleston, South Carolina, did purchase
owe equipment to communicatce with off-shore islands, ut this was
the extent of the onerations success,. :Jtubblef:ield became dis-
oned with the stock promotion schemes o is financiers and
drew co seclusion in his workshop. Ee receive identical
Un.red Staves and Canadian patents_in 1903 zo he induction system
ar. an examination of the basic principle ma pore useful.
QRM JULY 1979
10
NICHOLSON FILE GUIDE
iii iii PEmISTOn of the COOPER TOOL GROUP LIMITED
--- -----·-·- -----------··-- --- -----·- -
Drawfiling:
The Grip DOrawfiling consists of grasping
the file firmly at each end and
alternatively pushing and pulling
For files intended for operation the file sideways across the work.
with both hands, the more generally Since files are made primarily to cut
accepted way of gripping the on a longitudinal forward stroke, a
handle is to allow its end to fit into file with a short-angle cut should
and bring up against the fleshy part never be used as it will score and
of the palm below the joint of the scratch instead of shaving and
little finger-with the thumb lying shearing. When accomplished
parallel along the top of the handle properly, drawfiling produces a
and the fingers upwards towards finer finish than straight filing.
the face Normally a standard Mill
The point of the file is usually Bastard file is used for drawfiling,
grasped by the thumb and the first but where a considerable amount of
two fingers of the other hand. The stock has to be removed a Flat or
hand is held to bring the ball of the Hand file .(Double Cut) will work
thumb, onto the top of the file, in line faster. However, this roughing down
with the handle when heavy strokes leaves small ridges which will have
are required. to be smoothed by finishing with a
When a light stroke is required Single Cut Mill file.
and the pressure requirement is
less, the thumb and fingers of the
point holding hand may change
their direction until the thumb lies at
right angles with the length of the Lathe filing:
file. These positions can change as
needed to meet varying pressure
requirements. When filing work revolving in a
When holding the file with one lathe, the file should not be held
hand. as for filing pins, dies and rigid or stationary but stroked
edged tools not held in a vice, the constantly. A slight gliding or lateral
forefinger-instead of the thumb is motion assists the file to clear itself
generally placed on top of the and eliminate ridges and grooves
handle and in line with the file. While a Mill file is capable of
good lathe filing, there is a special
Long Angle Lathe file with teeth cut
at a much larger angle. This
provides a cleaner shearing, self
clearing file, eliminates drag or tear,
overcomes chatter and reduces
clogging. Uncut edges on this file
protect any shoulders on the work.
which are not filed, and the dog
which holds the workpiece
Lathe filing is usually employed
Carrying the file for fitting shafts Where stock is to be
removed a 12in/300mm or
For normal flat filing, the 14in/350mm. Long Angle Lathe file
operator should aim to carry the file is preferable This file will provide
forward on an almost straight line in the finish suitable for a drive fit. For a
the same plane c hanging its running fit a Mill file will provide a
course enough to prevent grooving. smooth finish. Where a fine finish is
Too much pressure often results in a required a Swiss Pattern and or
rocking motion causing a rounded Pillar file in No. 4 should be used
surface. Recommended Surface Feet Per Minute for Lathe Filing.-
Cast lron Approximately 150
Keep the file cutting: Annealed Tool Steel Approximately 175
Machinery Steel Approximately 350
One of the quickest ways to ruin Soft Yellow Brass Approximately 500
a good file is to apply too much
pressure-or too little on the Many lathe filers make a
forward stroke. Different materials of practice of not using a new file for
course require different touches: work requiring an extemely fine
however, in general just enough
finish.
pressure should be applied to keep In using the Long Angie Lathe
the file cutting. If allowed to slide file care should be taken at shaft
over the harder metals the teeth of
ends as this fast cutting file may cut
the file rapidly become dull, and if
too deeply.
they are overloaded by too much Do no run a hand over lathe
pressure, they are likely to chip or work, as oil and moisture can coat
clog
the surface and make it difficult for
On the reverse stroke it is best
the file to take hold. For lathe work
to lift the file clear of the workpiece,
that has oval. eciiptical or
except on very soft metals. Even
irregularly round form, the finer
then pressure should be very light
Swiss Pattern files are most
-never more than the weight of the
satisfactory
file itself.
JULY 1979 QRM 11
NE« STATIONS
VK7NED J.D. SMITH
VK7NVH V.A. HENDERSON 11 Bedford Street NEW TOwN 7008
VK7ZIS I.R. SYMONS 2 Cliffden Crt EAST DEVONPORT 7310
VK7NLH D.L. HOUSTON PO Box 91 GRASSY KING ISLAND 7256
VK7NTA 84 Madden Street DEVONPORT 7310
A.C. BARWICK 'Wivilda' Summerleas Rd KINGSTON 7150
VK'!NBH B.O. HEALEY
VK7NNH N.L. HILYARD 4 Sherwin Crt ROSETTA 7010
72 Bally Park Rd DODGES FERRY 7173
CANCELLED STATIONS
VK7ZLH R.L. HI3ERT Transferred to Q'ld
VK7TL T.J. MACHA
CHANGE OF ADDRESS
VK7ZMM M.C. WELDON
VK7ZSU/NSU S.E. MORGAN 38 Bartley Street HADSPEN 7257
VK7T T. WOOD 10 Boa Vista Rd NE TOWN 7008
VK7AC A.G. COKER 7 Maroney Street KINGS MEADOWS 7250
.,,,--, VK7PG P.O. GUENTHER Box 208 LAUNC2STON 7250
VK7YD L.B .. DIVE 2/72 Hill Street WEST HOBART 7000
VK7EJ 171 Mount Street BURNIE 7320
E.J. CRUISE Eighth Avenue DODGES FERRY 7173
3AT·TERY CHARGER
+ seTI,
+ NEW CC.T
17Ac '
Al.> I ~
-l....
. --·
lo-2o00/
Af f I
I
Modifications to "Electronics Australia" automatic battery charger
to eliminate SCR noise by using switching transistor, permitting
operation of rigs from battery, with charger operating.
73 de VK 7 ZFP
FOR SALE
40ft tiltover tower, spider quad hub and spreaders $50
David VK 7 NAD 002-438736
QRM JULY 1979
12
STATE NEWS
Welcome to the following new members;
DAVID BATES VK 7 ZDX Woodbridge
SAMUAL GINSBERG Rosn
BRIAN HALL VK 7 BH RosnJ
ROBERT HARPER Ravenswood
R. HEALEY VK 7 NBI Rosetta
B. HEALEY VK 7 NBH Rosetta
LES TOROK VK 7 NLT Warrane
DENNIS WEBSTER Penguin
VK 7 AWARD - advice has finally been obtained indicating that we
are not allowed to use the Tasmanian Coat of Arms. Other designs
are being considered and a draft of rules is almost ready to be
circulated for comment.
ARC Donations - a donation o£ $250 has been forwarded to Federal
Executive from VK 7. Included were amounts of $100 from Northern
Branch, $8/4 from North-west and $31 from Southern Branch. Thanks
to the following for their donations;
J. BALDOCK VK 7 NUB
J. BROWN VK 7 BJ
C. HARRISSON VK 7 CH
M. IVES VK 7 M
ON AIR COUNCIL MEETING - Council have a mid-month on air meeting
and invite listeners who wish to eavesdrop to find out current
areas of discussions. There would be opportunities for members to
add their comments. Next meeting 29 June 8p.m. 3595khz
MAY COUNCIL MINUTES - thirteen items of outwards and 11 items of
inwards correspondence. Time was spent discussing alterations
to membership ceiling, VK 7 award, P&T clerical procedures, VK 7 WI
broadcast irregularities, membership renewals, VK participation
in RD Contest, Devenport TV translators and Southern Branch 6
metre beacon.
P & T DEFT their new address is;
1st Floor, Continental Building
162 Macquarie Street Hobart
phone 002 205011
(postal address remains PO Box 63 Sandy Bay 7005)
2SI 3UREA_ NQTES
The present method of paying for outward cards appears to be working
quite satisfactorily but with the increasing number of users of the
Bureau a lot of time is taken up just looking after about 110
individual accounts, quite apart from the actual handling of cards.
It has been suggested that we use stickers as an alternative, thus
eliminating the book keeping and after reference to the Branch QSL
Officers it has been decided to make the change.
For those not familiar with the system, sheets o£ 100 small self
adhesive stickers will be available from Branches and the Bureau
at a cost of $2.00 a sheet and one of these stickers must be put
on each outward card.
To effect the changeover everyone with a credit at the Bureau on
25th July will be given stickers to the equivalent of his balance.
These will be distributed at the August Branch Meetings and I will
post those for the few country members concerned. Thereafter
further supplies can be purchased as required.
JULY 1979 QRM
QSI UREAU _QT_ES (Cont'@) 13
Please do not forward any cards to the Bureau after the 25th July
until you have stickers. Those who hand in cards at the August
Branch meeting may pay in cash if they wish on this occasion.
This will save the trouble of having to put on stickers there at
the meeting after you receive them.
A check for the month of May showed that there were 86 separate
entries to the accounts and cards handled were IN 3359 OUT 2710.
73 de Chas. Harrisson VK 7 OH
QSL Manager
******************************************************************
VK 7 CH WOULD VERY MUCH LIKE TO HEAR FROM ANYONE WHO KNOWS THE
WHEREABOUTS OF DXCC, WAZ AND WAS CERTIFICATES OF HIS BORROWED
FOR T.A.R.C. 78. THESE HAVE NOT BEEN RETURNED AND THOSE TO HOM
THEY WERE LENT DO NOT KNOW WHAT HAPPENED TO THEM.
******************************************************************
Chas says that "although it's many years since I took any interest
in Awards "the missing ones would all be dated around 25 years
ago and they do have a certain sentimental value." check your
papers in case they got mixed in with them and if so please send
the Awards back to Chas.
Editor
NORTHERN BRANCH QSL'ing
To be of service and assist members, the following points are
recommended for tchose QSL'ing.
CARDS - no alterations should be made on cards - time must be in
GMT - mode should be indicated ie 2 x SSB, Slow Scan, CW etc -
frequency or band - day month and year must be shown.
Call sign of station worked or QSL Manager to be marked on the
back of the card along with the sticker.
Provison has been made at the Clubrooms for the cards to be
deposited at any time. Cards should be in bundles if possible.
Those members who anticipate using the Branch for outgoing QSL
cards should advise Col Perger VK7 KW of where they can e
contacted should he notice obvious mistakes on the QSL card in
order that it can be corrected before being sent to the 'Bureau
for onward transmission.
JULY 1979
14 QRM
NORTH WEST BRANCH NOTES
The monthly meeting of the N/west Branch was held at the new venue
of Penguin High School. Attendance was extremely good, approx 54
persons plus Guest Speaker and high school Principal. The meeting
was advised of telex to hand advising acceptance of the application
for a Club Station by P&T. THE CALL SIGN IS VK 7 NW AND THE QTH
WILL BE THE PENGUIN HIGH SCHOOL. Application for membership was
received from Denis webster. A suggestion was received to nominate
a net frequency on 10 metres for use by Novices as a liason in the
N/West Area. No frequency was given at that time. However as an
interim, a frequency0£ 28.490 repeat 28.490 has since been suggested.
'The meeting Chairman outlined various activity groups planned for
implementation with-in the N/West Branch. Basically they are;
1. ATV Group
2. RTY
3. MICROPROSESSOR
'+. HF
5. VHF/UHF
6. CONSTRUCTION & SERVICE
7. ACTIVITIES INCLUDING FUND RAISING
AND FAMILY PARTICIPATION
Group leaders have already been found for the ATV Group in Tony
3edelph VK 7 AX and Winston Nickols VK 7 EM. Steve McDonald has
agreed to act as Group Leader in the MICRPROSESSOR Group.
The 1st ATV group activity nights will be on Thursday 21st June and
Friday 29th June. (these will have taken place and we sincerely hope
they were a great success - Ed)
Tony VK 7 AX also outlined to the meeting theacquisition of a Marconi
Camera Chain complete with lots of ancillary equipment, for resale
at some future date. It was proposed to set up the Camera Chain
within the High School for public display and use within the ATV
Group. The meeting was advised of a letter from N!est Branch to VK
Broadcast Committee seeking permission to use portions of their
weekly broadcasts, in particular the 'ATV Segment' for use as ON AIR
discussion within the i/west Branch. It_is planned to use Repeater
3 in conjunction with the 10 metre net•28.4-90 previously mentioned.
The meeting concluded with an interesting lecture and discussion by
Inspector Lello of Burnie Search and Rescue. Inspector Lello out-
lined some of the functions and problems of Search and Rescie
operations, in particular Land Rescues such as Cradle Mountain area
etc. He offered some challenges to members in relation to commun-
ication problems and it is hoped and anticipated this Branch can
assist in future operations. These notes are only a brief regime
of happenings in the N/West Branch. More to follow on future
broadcasts 73 de Tony VK 7 AX
JULY 1979 QRM
15
LETTER TO THE EDITOR
Since being a member of the WIA, I have consistently enjoyed the
contribution of VK7NOW (Jim) in virtually every issue of QRM and
have forwarded the following notes which not only will be of interest
to Jim but I trust to most other readers as well.
Jim has an enthuiastic interest in all spheres of communication,
particularly the earlier days as many well be aware of after visiting
his QTH. Some time back, he contributed a very interesting article
on sound recordings and I pass on the names of publications where
much more information can be obtained in this field. I obtained
from an address in Canada (after a very long search) a copy of the
"VICTOR MASTER BOOK", Vol 2 by Brian Rust. This publication deals
specifically with the recordings issued by the Victor Company bet-
ween 1925-1936 and includes reference to Victor's first LP produced
in 1/3
33 1931 RPM.
which was played on the Victrola with a motor geared to
In a later issue, Jim dealt briefly with the career of one Lee
DeForest. Whilst in Adelaide (SA) earlier this year, I was most
fortunate to obtain a copy of "Electronic Pioneer -- Lee DeForest"
oy I.E. Levine. This is a 192 page account of this pioneers
contribution to the electronics industry. Adelaide is a very happy
'hunting ground' as in that fair city, one can also visit and spend
hours at the Telecommunications Museum, Electr House, 131 King
William St, Adelaide. Whilst I was there, one could see a contin--
uous display (Monday's to Friday's) of early equipment in the Radio
Telephone and Telegraph fields. Admission is free, the staff are
the most informative and helpful. The final "icing on the cake"
so to speak was to be able to obtain the excellent publication "A
History of Radio in South Australia" 1897- 1977 by John F. Koss and
currently available through ERNSMITHS, 50 King William St Adelaide.
The publication is extremely well illustrated and of particular
interest to QRM readers will be the two chapters "Hello CQ" and
'"The wonder of wireless". With the 65 pages devoted to these two
features the story of the Wireless Institute and it's earliest
members mentioned in an earlier issue of QRM, a current reminder
will be timely. Anyone interested in further information on any of
these publications can write to me.
Yours faithfully
Hedley Charles - L70126
49 Spencer St Burnie
PH. 31 170'6
PH- 35 115't
VK ELECTRONICS
57 WEST PARK GROVE BURNIE 7320
- (VIC111'1f! N"'S)
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« Rt. Era€fr 7250
1ii New $iD %
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PO Box 275 Launceston Tas 7250