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BULLETIN 1SSUED BY THE NORTHERN PO BOX 1010
BRANCHES OF THE WIRELESS INSTITUTE LAUNCESTON
OF AUSTRALIA TAS. DIVISION. TAS. 7250
SEPTEMBER 1973
VOL. 3 NO.
REGISTERED AT GPO HOBART
for transmission by post
as a periodical. CATEGORY B. PRICE 1Qc
EDITORIAL BY BASIL VE6BB / VK7BL
TWO LOOKS AT TASSIE - WITH 9 YEARS BETWEEN.
"There is no place like home" That's a cliche, very timeworn but
just as valid now as when it was first penned.
It's nice to be back on & visit and renew old friendships while
2
striking up new ones.
Naturally the amateur scene in Tasmania, as everywhere else, has
altered radically, and an objective appraisal may serve to facilitate
some self examination. If I may, L would like to point out some
features that have been quite noticeable as compared to 1964
when 1 lefte.
On the positive side, there is a very pleasing growth in the use of
channelized VHF FM communications. If there is ever going to be
an improvement in communications technology it will probably be
in the VHF - UHF field, and amateurs here are demonstrating
their willingness to be "in the thick of it" at the same time,
the proportion of Tasmanian (and Australian) amateurs engaged in ~
satellite communication is quite large compared to, say, Canada.
An offshoot of this is the Mt Barrow repeater, its coverage is
fantastic, my congratulations to all who participated in its
design and erection.
cont. page 2
SEPT. Lth NORTH WESTERN BRANCH, LAKINS HALL, ULVERSTONE.
SPT. 14th NORTHERN BKANCH, AEB ROOMS, HIGH ST.
SEPT. 22nd n1NGS MEADOWS HIGH SCHOOL.
This will be the only class during September
due to school holidays.
OCT. 20th - 21st 16th JAMBOREL ON THE AIR.
For details see A.R. July '73 page 20
Qe s ate
BULLETIN OF THE NORTHERN BRANCHES OF THE W.I.A. TAS, DIV. Sept. '73
: Page 2
New faces amongst the 42 people who attended the Northern branch
meeting included, Bill Tanner VK7TE , Keg Binns, John Doolan,
Bruce Atkinson and Max Brooiks.
Two items of correspondence were the letters to and from the
contest manager relating to the use of repeaters in the R.D.
contest. (this matter has since been taken up by the divisional
secretary and has resulted in a reversal of decision )
In his financial report the treasurer VK7ZAH said that sales this
month amounted to #441.00 and that we have a bank balance of $661.00
John VK7JV reported that the Clubhouse account is still inecreasing
allthough more slowly now and the ballance is $915.00
Lindsay VK7ZLD spoke about the Hamfest arrangements and a full
report appears on page 4 .
It was passed by the meeting that the Hamfest committee be given
$70.00 as a working capital, more later if required.
After the meeting closed members showed some of the equipment
they have built in the last year.
VK7ZBY showed the frequency counter as described in QRM
VK7ZLD had quite a selection, an 1IGL receiver, 2M walkie talkie
and a signal source for carphone receiver alignment.
VK7ZRF allso had a 2M walkie talkie as well as a sync pulse
generator and a 6 - 30 Mhz receiver.
VK7RH showed a speech compressor that he has been experimenting
with. ‘
VK72GJ impressed us with his new 6 metre transverter using a
6/40 in the final. this unit will be described in QRM
~in the near future.
VK7KW has obviously been quietly working away while we weren't
looking and produced a bLeltahet type receiver.
ok % ok ok ok ok ok %k %
cont. from page 1
Another very positive is the fact that despite relatively limited
(and expensive) parts, in general the state of the art knowledge
is extremely commendable and in many cases far exceeds amateur
requirements. A very large number of amateurs are still willing
to experiment, to try something new, far more than those in Canada.
So muech for the positive changes, what about the negative points
that have been noticed? For one thing friendships now seem a little
more restrained(perhaps because of the increased number of amateurs)
Ask yourself now, do you realy know that amateur down the street,
or over the hill? sure you can talk to him on 2 , but is that realy
getting to know him? (for one thing he can't say all he might wish
to over the air) Why not cultivate a friendship with somebody
living close by, you may be surprised.
There is allso a certain amount of '"clique-ishness" which is quite
noticeable too, and was certainly not a feature when I left.
Some Hams (and I use the word advisedly) have their own little
groups and discourage outsiders, perhaps you even know one or two
yourself, other changes that are neither good nor bad include,
ofcourse the dominance of SSB as a mode of communication, the
consequent large number of bought rather than built stations.
The growth of the Northern branch, and the large number of HF
directional beams (bought and built) all this makes Tasmania a
little different for me now, I am allmost a stranger.
In conclusion, I would like to take this opportunity to thank all
those who extended their hospitality during my holiday here.
It all helped to make my stay a very memorable one.
Look for me on 20 metres SSB or RTTY.
73 Basil
BULLETIN OF THE NORTHERN BRANCHES OF THE WIA TAS. DIV. Sept. '73
Page 3
NORTH WESTERN BRANCH NOTES by MAX VK7MX
To those of you who do not care for my notes.l have news for you,
you have another 12 months to get used to me.
This month's thought provoker. How much should one do for the W.I.A.?
There is no obligation, Why bother at all. Why do we bother with
ham radio ? To the technically minded it's a challenge, there is no
set pattern, rather a dozen different approaches.
And so we become absorbed in it. there is some distinction in
wearing a W.l.A. badge. We may be screwy but it takes brains.
The whole objective is to communicate and to do this we muat have
the use of frequencies, and they are getting scarcer.
The W.I1.A. is the one voice that is recognised, the more we support
it, the louder the voice.
We can all contribute in some small way to the general effort which
in the aggregate will constitute a powerfull organisation, one
that will be respected and listened to when most needed.
Active participation does have its reward and I should Knows
Now. to current events. The Annual meeting of the North West Branch
was held on the 7th of August with an attendance of 21.
The most important business was the election of officers for the
coming year. Results were as follows:
Pregsident MAX VK7MX
Vice Presidents IAN VK7ZIE and SID VK7SF
Secretary DAVID VK7MS
Treasurer GRAHAM VK7ZAQ
QSL Officer HAROLD VK7MZ
BRANCHCorrespondent MAX VK7MX S
We were delighted to welcome VK7BL Basil (VE6BB) 7JV, 7KK, 7PD,
Steven VK7ZSF and 7RH, thanks chaps for cominge.
1t was a jolly little meeting, with some unusual happenings but
it all worked out and no one was dobbed in.
All were willing to do their bit.
The past President presented his report outlining progress during
the year, but allso some caustic remarks directed at most of us,
we were all very sade.
After the meeting closed we were entertained with some movies of
our star cricketers and it became fairly obvious as to who really
won. We allso saw some Ladies and some shots of the last Evandale
Hamfest.
Basil presented some slides of his home location in Canada including
some of his school. We were fascinated by a number of points
in one picture, six in all. We wish Basil the best of luck in the
future which from the pictures will be full of opportunity.
Our new secretary turned up beautifully turned out, dressed
somewhat like a kaleidoscope, the impact was startling, I'm jealous.
David 7MS is the proud owner of a new ACITRON S5SB rig, it makes a
big noise, locally anyway.
Rumour has it that a local ham now has a circuit board stomach,
mistook the glass of ferric chloride for a glass of Fanta and
is now suitably etched.
Again rumour has it that some sort of disaster took place in &
very small area in the shack of Ian 7Z1LE, some beating about the
bush on 2 metres rather confirms this but appart from a 20B in
the car one can only surmise. Its a cruel world.
7MX in collusion with 7NR have built constant volume amplifiers
to poke in front of the SSB rig. Found them to be winter jobs only
as in summer flies and mosquitoes will cause heavy QRM.
Harold 7MZ is having a short spell in hospital, he looks fine to me.
Back to the cards Harold.
CU next month MAX
geit e
BULLETIN OF THE NORTHERN BRANCHES OF THE W.I.A. TAS. DIV, Sept. 73
Page 4
50th HAMFEST VK7
24th & 25th NOVEMBER, 1973
EVANDALE MEMORIAL HATL
The Hamfest Committee held their first meeting on Tuesday
Tth August at the home of VK7ZLD, who was appointed Chairman
for the committee. I
The very successful 1971 Hamfest would be used as guide lines
forthis our 50th Hamfest, and registration fees would possibly
be the same as for 1971.
The Hamfest would be centred on the Memorial Hall, caravan and
camping would be available at the Evandale Show Grounds which
are only a short distance from the hall,
The Committee Member responsible for the various areas :-
Brian VK7ZBY & Bob VK7ZRF ---- Antennas,Entertainment,
Hire of hall and liaison -
with Evandale Council.
Joe VK72GJ ~-= Operational Equipment for 6M and above,
and operators for same.
Robin VK7RH ~-~~ Provision of HF Egquipment and operators.
Gordon VK7GW ——- Trade Products and Literature.
Kevin VK7ZAH —== Equipment Store, cordials and sweets.
Lindsay VK7ZLD —-- Catering,Equipment Display(old & new).
Norman VK7NR ~-- "Mobile Clinic" and Test Centre.
Steve VKT4SF ~—w Publicity.
Would any members who have ideas please forward them to the
comnittee so this Hamfest will be & "bigger and better" Hamfest,
w————— remember it is the 50th Year,
. Hamfest Committee.
EQUIPMENT STORE NOTLE
Due to the application of surcharges to imported capacitors
"most capacitors will increase from 2 - 10 cents.
The goodies we have on order for you at the moment include:
IED's (light emitting diodes), electrolytic capacitors all
values up to 220 mf, 1000 pf bolt in type feed trough capacitors,
1000 pf ceramics 500 volt,SCR's and 2pole L position wafer switches.
IC's in stock include: 7400 , 74Ok , 7420 , 747L , 7490 , TL93,
and 7495 .
IGL tranceivers and converters are still very popular and another
order is being made up at the moment.
Fibre glass blanks have being received and are allmost gone.
Ferric chloride is sold out, if there is sufficient demand we'll
get another batch. Abatech is 50 Kge
{fr\,aR-IVIn
BULLETLN OF THE NORTHERN BRANCHES WIA TAS. sept. 1973
: Page 5
TECHNICAL ARTICLiS OF LNTEREST by VL7PF
HBLICAL MOBILE ANTANNA HAM KRADLO LEC. '72
This 1s a very gocda article, detalls are given of how to windan
antenna for a single band anc allso for one that works on all bands
40 - 10 metres.
This @erial shows resonance and impedance suitable for P1 MATCH
networks.
Typical resonances are 7.05, 14.2, 21.1, 28.28, 31.8, 3742, LL.5,
56, 67 etc Mhz and by adding a loading coil can be used on
160 and 80 metres.
HIGHPQWER
Eimac advert says a Bendix made phased array radar uses 5.184 of type
LCPX250K tubes of 10£W peak output each, driven by 10.3268 planar
triodes, the total cost for tubes for this transmitter, $336.592 .
MONOLLTHI
MICROTRANSMITTuR
C Australian Llectronic aingeneering.
An American company, Lithic Systems Lnc. has developed the first
commnercial of a series of micro transmitters.
The L 2000 1s aimed at HF to low VHF, AN and Pulse modulation
applications, later versions will be aimed at VHF FMand SSB
applications as well as AM and Pulse.
in a 170 pin TO5 package is included an oscillator followed by
buffer and output stages, a power supply regulator, modulator
pre amp and modulator output regulator.
To use as an AM transmitter external requirements are, a crystal
and output tank circuit, six condensers, four resistors and
a small dynamic speaker as microphone,
A 27 ¥hz AM transmitter performance, CW output 100 Mw, CW supply
current 50 4A, All output 50 Mw, AN supply current 28 MA, AM 90 %
modulation with less than 10 % distortion.
HAM RADIO for FeEB. 1973 carries an advert for Semiconductor
Supermart which says, coming soon the LP 2000 Micro- transmitter.
TUNABLESIXANDTeNMATRE PHASKLOCKEDLOOP HAM RADIO Jan. '73
This is a circuit for an tunable injection oscillator for use
in converter or transmitter mixer anpllcaulons.
A free running oscillator or VCO operates on the output freguency
and is mixed with a crystal oscillator to produce a low LF
which is compared with a tunable oscillator and a correction
voltage is developed to make the VCO follow the low frequency
oscillator. ;
This is called a phase locked oscillator. This circuit differs
from others through the use of a digital IC type D flip flop
as 2. mixer.
WWhen used in this application it functions as a harmonic mixer
in that the crystal oscillator injection need to he only
one eights of the required frequency.
The output is compared with the tunable oscillator by using
a IC phase comparator MCLOLP.
To produce an oscillator tuning 48.4 to L9.4 Mhz for use in a
50 Mhz converter with a 1.6 Lhz 17, a cryotal on 6 Mhz will
in the D flip flop mix to produce 48.4 - 48 = .4 Mhz
S0 a VFQ from 400 to 1400 hz will lock the VCO to cover
the reguired range.
. Vo~
tieile e
SULLATIN OF THI LOVNISRT Z0K3S7IA TAS September 73
page 6
TaCHTCALARTICLE = VETZRY
4TRIJLICY
A 250 i
A2oV dtu
il COUILR
Ll . PART S
Count Gate Control Circudtry
‘he Count Cate Control Losgic (the cireuit of which apnears at Pig. 10)
conzists of two J-II flip-flons, a two input exclusive "03" zate, and one
inverter. The two flip-flops are provided by a dual J-¥ flip-flo»n type 7473,
one hali of which is used as the gate control F/», whose clock input (C) is
fed with the selected timeba e signal from the tirmebase select switcu. As
the gate control must only be allowed to open the counter gate for a single
tinebase signal period for each measurement, its operation is controlled by
a lock-off signal apnlied to its DC resct terminal (R). The lock-off signal
is provided by the second half of the 7473, which switches to the setstate
inmediately the gate control 7/ returns to the reset state after opening
and closing the count gate., The lock-off signal is applied to the DC reset
input of thegate contro; R/F via an cxclusive "ORr" sate (ty-e 7486). The
purpose of the "onr gate is to allow the gate control T/ to be reset, along
with the lock-off #/7, Ly the normal instrument reset pulses.
Before describing the operation of this section we must first understand
the operation of some of tue devices used in this circuit. First the dual J-K
naster slave #/7 (7475;; with a »nulse train ap-lied to its clock input "on,
the infonnatlon of the J and I 1nputs (Liogic 1) enters the master section when
non ooes high. Afterwards, when " goes low, the information is transferred
from the master section to the slave section and apnears at the outputs.
Bcecause of this method of operation the pulse period of the output is the same
as the input. The other section that may need some explanation is the "OR"
gate which is a dual device of which only one section is used. The bvest
method to show how this gate operates is by the truth table, which apnears
below.
A and3 are inputs,
2 is the output.
@rom the truth table it can be scen that the 2 outrut is low when both
inputs are low or high,
Other devices used are T741I04 inverter, a dual TATD vower gate 7440, of
wiaich only one section is used here and a (uad two 1nputLAuD gate 7400, The
operation of these devices have been explained in previous articles.
The onsration of this section is now as follows: Consider the counter
reget prior to the count gate crening and no tlmcoaue sigmal ap»nlied to the
clock terminal of the mate control F/F., New apnly a nulse train of the correct
shape from the timebase via the tinebage select switeh to the clock terminal
of the gate control rlip-flom. As cxplained previously, wien the clock terminal
won eoes high the information availableat the J and 77 inputs enters the master
section of the 7/7, by the ) and § »ar outputs doc not change until the clock
terminal goes low.
Then this occurs, tha | outmut goos to Logic 1 and the ) bar outrut goes
Y
e -he .. @
BULL T O Ia oA 4SS JTA TAS Scptember 73
to Logic O cic 1 Trom the to both the count gate,
trere J" on o ate anrd to the . fln,loawohffy?’Qad
section of 737?}. It can be seen tnat this effect is exactly the sanze as in
the gate control scction F/F in ~o nuch as the information at the J and I
termirals has enrtered tie rnanter cection ~hen the ) output of +n gate control
/P went to Logic 1, but cannot apnear at the outputs vwntil the outnut of the
sate comtrol F/F returns to Iogic 0. T.is occurs vhen the next ‘ul°° input to
the gate control *Vn clock terminal rises to Logic 1 and back to Logic 0, and in
doing so resets the gete corntrol /A, At this point a number of things occur
simultaneously - the count gate closes because the ) outnut has returned to Logic
0, and the loc¢-off flip-flon =etg. The | bar output of the loclk-off F/F which
was at I.ogic 1 prior to setting, now goes to Logic 0. This Logic 0 is apoplied to
gate 4 of the exclusive "OR" sate, the other gate (B) is fed from the reset line
via an inverter (74104 Ac the reset line is at Logic 1 the inverter applies a
Logic 0 to gate3. “oferring to the truth table of the 7486 will show that the
Q output will now go to Logic 0, having been at Logic 1 prior to the lock-off F/F
setting. This Log c 0 is ap“~1sd to the DC reset terminal of the gate control F/PF
which forces that I/F to remain in the reset condition. Upn until now we have
opened the count gate, counted the input siymal, stored it for displaying and re-
closed the count gate. As explained in Part 4 page 7 the counted signal is applied
to the readout devices at a count of 7 and at the count of 9 the counter is reset
to 0 prior to the count gate reopening. 1t is at this count of 9 that the gate
control circuitry is resct for the next overation.
The output of the 7413 schumitt trigger (see page 8, part 4) is normally at
Lozic 1, “ihen the reset pulse is gen@rated, this outprut goes to Logic 0. This
Logic O ig applied to 3 noints: 1. The 7440 1TA'D nower gate for resetting the
main and subtracting decades and the overflow F/F via a T400 which is fed from the
output of the 7440. 2, 7To gate » of the 7486 exclusive "OR" via the 74H04 inverter
and 3. To the DC reset terminal of the lock-off F/F. then this reset pulse is
apnlied to the lock-off F/F its § bar output returns to Togic 1 (7/F reset), This
Logic 1 is applied to gate A of the 7486. At the same time the Logic 0 from the
reset linc is inverted by the 741104 to [ozic 1 and applied to gate 3, and again
referring to the truth table for the 7486 we will find that the Q output will still
be at [ogic 0, therefore the gate control F/I w7ill still be held in the reset
condition. At the duration of the resct nmulse the reset line will return to Logic
1. This Logic 1 level on the reset line will now be inverted by the 74104 to Logic
0 and together with the Logic 1 from the O bar output of the lock-off /P will Allow
the Q output of the 7426 to go to Logic 1. “hen this occurs, the gate control F/F
is ready to perform another gate ovening function, where the complete procedure is
completed.
Another function in this circuit which plays no part of gate control is the
nrovision for bringing the timebase Irecuencies out to - socket for testing and
calibration purposes. This is provided by a 7400 feeding the second half of the
7440 used in the reset circuit. These two gates are fed from the wiper of the
timebase select switch. The 7400 is used to reduce loading on the divider chain
and loading reflected back from the timebase test socket. The 1.5 T resistor
between the soclet and the 3 output of the 7440 is to »nrotect the 7440 chould the
outnut be accidentally "flOLted to earth,
= S
iWwWe e lse
SULLATIY 0P TEE LOUTEAR: 20083 /IA TAS September 73
nage 8
2ECLICAL ARTIOLT (Comt)
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Q-R-}I‘I-
BULLETLIN OF THE NORTHERN BRANCHES OF WIA TAS. Sept. 1973
Page 9
SPEMCH COMPRESSOR by VK3TN reptinted from G.A.R.C. newsletter,
This speech compressor circuit, supplied by John VK3TH is used
with an FT101 with excellent resultse.
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BULLETIN OF THE NORTHEKN BRANCHES Vi.l.A. TAS. Sept. 1973
' Page 1Q
reprinted from Westlakes Radio Club - Newsletiter.
AN _EXPERIMENTAL DIRECT CONVERSICN RECEIVER: PART 3 - by D.CROFTS
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CONLTCTIONS
DaTelia PACKAGTE
the data including the schemetic for the wA741,
amplificr constructed on o single silicon
chip, using "0CenG. 4% A8 designed for ease of application
and high pn»Cornnne imal frequency compensation components and
is fully »w Yected
U titions oceuring ot either the input
or ~bkput, The ampli un AID can accept (a wide range of input
volbapoes, nacansn ]
hirch reliability with low cost,
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2 500 m¥ and the
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BULIKTIN OF THE NORTHERN. BRANCH&S W.I. A. TAS. Sept. 1973
Page 11
'wTDIRTOT PART3 ~Do.Crofts,
cudic anplifier I will show you
<,
= 670 _preeswnplifics. It uses a 203565
{e2M = , 7641 ~tc(~fu Silicon)e
Yo, r.Afléfi:L] ’;;Tfl&
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o ure. it as o] pre-amplifier
T e A woe o a low nolre transistor,
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1 i BC109
BC100 already ti
alread v mentioned,
B T The secend audic amplifier is a very high
== Botton o 1t ic directecoupled and has a
S g 2 .
v VIEW cxcess of 100 dB, The three trans
\
- \r used should be »f the type mentioned
- T. ny comments regarding
> > noisc
, also
09
SA 2T =ne should be taken to avoid any
= Ly oin the amplificer, and this
should be checked befors the cow wooegiver - if nccessary increasing
the value of the decounling two stagen. This amplifier,
the Product Detect o, ‘ilter, could form .o complete
high performance poxs
Hi~7 phones or to
Anplificr for
RQX”' loud.spealer,
T
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AOTe I, Djfl] O"n1uf iz in the order of 1,5 Watts
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1 this will increase the
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BULIETIN OF THE NORTHERN BRANCHES W.I.A. TAS. Sept. 1973
Page 12
AN DYPORIMENTAL DIRECTCONVERSIONBECRIVER : PaRT3,CONCLUSION
The amplificrs shown are only a portion of the amplifiers capable of being used
in the recceiver, Usc what "vu connider best, consistant with availability and
cost. TBxperiment with wha’ vou have and above all, do not megard IC,s as *'Black ’
Reasts', find out wha't you can abouh then - this is the esscnce of amateur radio.
Tinally; T have an aliernative Produet Netector 4o +that already discribed, it ,
uses 2 transistors and pexnforms the same as the previcus cne., The transistor so -
used, can be ¢ BC107-~8=9, BIM15, BPI8A-3 ox any sinmilar R.P. silicon transistor,
The lowem cost of this detochtor nav make it more atitractive to some constructoras,
The same oscillator is used.
IV
\\l;! | r T L
= = 1002 >
! o l < log
04 i <} Uy d (/f'
< o - . -
i thee < § 7 'fi e.f;,,_{k_,_fi.hudlo Freq, Output
; e @ = ; L (May neeéd filtering)’
e
Yo=
o ____3____ W 07
_ D
,r'
{ i¢ ! i\ N &/) \g‘Lfl““
S ‘ 'J! Osce. Inputa
T e : \\4}“‘“‘r““” e’ bP
5o
5o 3. : ! : B4
Original ' e L L >
Toroia | - < S5%0unm 2 et ‘
. . 'Te fi,fifik* > < 3
Signal 0011j, i ol t
iA i o . .
If anyone hmb any o“nstruclvcn problems, or any suggested alterations and also ?
circuitry a’ ‘ons, please write to me at the Club postal address, We are now
thinking of 1ATing a kit oult of the receiver availablie. We would he intexested
in your oninicn,
A_TWO_METRF, BRAYO THECHEAP. oT erESs
7(’0\/!’“‘ o Tt LN, :
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bLPN' l i i Q- 5Ll N T
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! i : 7
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16 /2 i 26 | 2o
"“”"“, T
! $ i
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¢
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P8 260
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How dnes it pexforin ? It has a forward gain »f 6 ta 8db »over a °
equivalent to increasing powexn four tines. The front to back ra
Q
and by carcful pruning »f the d»iven clenent, it is possible to abtain an SWR of
dovn G0 125 46 1o The bean is nade of A9inches of tinber by 1 ¥ 2, The clenents
are nade of {; dia copper o» hracs nods. Thednwiven element is natched to the
feedline throush a NGERAST coax dclita nateh and balun, Tune up is best done with
the antenna in a cleax spot pointed shtraight up ot the sky, Pruning the driven
elenent will give the best SWR natch. Mount horizontally for AM and vertically
for T operations, B S —— S
QeReMs
BULLETIN OF THE NORTHERN BRANCHES OF THE W,L.A TAS, DIV,
Sept. 1973
Page 13
NORTH WESTERN BRANCH ANUAL STATEMENT OF ACCOUNT
AB AT 31 - 7 - 1973
DEBIT. RECEIPTS
.
Purchase of equipment 428,57 Cash in hand I1.8,1972 108.67
Hall Rental 18.00 Sale of equipment 446,07
Q.R.M. Donation I15.00 Hall Colledtions 8.26
QeSels Bure 2.00 Zone Fees 28,00
Subs to Federal Ex. 17.00 Subs, 17.00
Cakes for Ladies night 6.45 Profit on 432Mi{Z_Cémverters. 4,00
Xtal Refund (B.Groom) 10.00 Xtal Refund 49,00
Annual Dinner 274,00 Annual Dinner 288,00
Printing (Dinner) 11.50 Bank Interest 4.46
Cheque Book 1.80
TOTAL $784.32 TOTAL $953.48
Balance at Bank 100.42 $ 953.46
To be paid in 88,72 Less 784,32
189.14 TATAL $ 169.14
Less unpresented cheques 20.00
TOTAL $§169.14 Asaets Balance in hand $§169.14
Equipment on hand § 65.61
TOTAL ASSETS. 234,75
NORWIND
g
ELECTRICAL ENGINEERS
SPECIALISING IN MOTOR REWINDING AND ASSOCIATED.WORK
W
o
27 SUNCREST PLACE, RAVENSWOOD
¢
TELEPHONE 391515
?
Athol Lawes Electrics
135 HOBART ROAD,
KINGS MEADOWS, LAUNCESTON
Telephone 443119
TRY US FOR YOUR NEXT APPIIANCE |
YOU WILL FIND IT EASY ON YOUR POCKET § & &
RO R OK % %}
»
4
HAWADS HAMADS HAMADS
FOR SALE
AWA MRT 25a carphone with xtals for ch. B, L4, 1. $130.00 !
IGL 6 metre converter with xtal £ 42400
PYE Mk 3 with FET pre amp, xtals for 53.032, 5W out & 12,00 S /
No 10 xtal calibrator unit 2 8,00
Sun yagi 14 element, built and tuned £ 15,00
WANTED TO BUY OR EXCHANGE
A VARIAC, STATE PRICK AND CONDITION
0 - 30 Pf variable vacuum capacitor 10 KV rating
VL72GJd 40 Lavender gr. Launceston
: Btk ese i oz s e sp e sk R e e R sl s e e L ol
MORSE_KEYS ARE AVAILABILE
CLIPSAL MORSE KEY £9.35 + 15% tax. See Norm VK7NR for orders
@¢
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. . . :
3K oL 3R N s sl st sl sk i e niz o ol ne e o sl T ol sl sk Besle skl ok LA
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