QRM
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BULLETLN ISSUED BY THE NOKTHERN PO BOX 1010
BRANCHES OF THE. WIRELESS INSTITUTH LAUNCESTON
OF AUSTRALIA TAS. DIVISION, TAS. 7250
NOVEMBER 1973
VOL. 3 No 8
REGISTERED AT GPO HOBART
for transmission by post
as a periodical. CATEGORY B. PRICE 20c
THE WEEKLY SUNDAY BROADCAST
Have you ever wondered how our broadcast officer Reg VK7LK
manages to get sufficient information to give a half hour news
broadcast each week?
Have you ever thought how much work goes into it? Besides reading
every radio magazine and listening to broadcasts from other
divisions he relies on YOU the member to let him kKnow of any news
that you may come across,what you are doing in the way of building
of equipment or the DX you have been working whether HF or VHF.
After all a lot of news is nothing more than gossip.
It is so easy to elect soméone to do the job for you and then
forget all about it until next years anual general meeting, when
Just a few minutes of your time would save him hours of sleuthing.
How about you,are you helping the people you elect and showing
you care what happens in your branch? Think about it.
7% John AX7JV
' _MEBTINGS
Nov. 6th North West Branch, Lakins Hall Ulverstone
Nov. 9th Northern Branch, AEB rooms , High st
Both branches are having a slide evening, NW members
are requested to bring some slides along,
Northern branch has some 20 slides of the Oscar 6
satellite,
Nov. 24th and 25th Hamfest at Evandale, keep this weekend free.
YRCS
Nov. 10th Kings Meadows High School, room %8, block B
: this is the only class in November due to the Hamfest
Dec. 8th Kings Meadows High School, room 38, block B
Qo Ro M, November 1973
Page 2
The meeting of the Northern branch held on Oct 12th was chaired
by Peter VA7PF and attended by 46 members.
Peter welcomed visitors David VK7ME and Angus Robertson from TNT 9
Kevin VK7ZAH reported that equipment sales for the month
amounted to $477.00 . Kevin said that there was difficulty with
30 day accounts as by the time these bills were approved for
payment they were overdue resulting in some cases in nasty
——
letters from our suppliers.
The meeting decided to authorize the treasurer to pay all urgent
bills without meeting approval,
Oscar. Peter mentioned that Oscar 6 was now one year old and
still functioning very well. On the guestion of repcaters Peter
said that it is our intention to change frequencies at the same
time as VK3 and VK5, this offcourse is subjecl to the receipt
of official approval.
Hamfest, Lindsay VA7ZLD reported on the progress made and appealed
to members for donations of hot and cold dishes for the [Saturday
evening meal, he also told the meeting of the success Gordon VK7GW
has had with his request to trade for literature and prizes,
Lectures. The meeting discussed the lack of these , Reg VK7KK
was nominated and elected to the post of lecture officer,
The meeting closcd with a very interesting and humerous talk
by David VKYMS on the pitfalls of horse and cemel racing after
which a lot of interest was shown in the Acitron tranceiver
which David had brought along.
sl sl sl sk e ot 2 sl e sk st slesk skosk
«f . o owbe ala Wt abe ol afe ots 3T O
Our congratulations to the VK5 division on their magnificent
efffort and win in the RD contest.
S'eslg sle
shsko s oats
sl Mooate
et sle e st
skslk skol eF3 3
Rk ok
Congratulations to Daniel VX77DA and Mike VK7ZWW on their recent
pass in the smateur exams, both of them can be heard on CHl.
o ale abais sle aleR it ale sl il gt ats b 2l she
LR R AR R S
.....
of the JOTA and the number of contacts made, however 1 do
remember that he saild the whole thing was a great success and
many contacts where made both with VK, ZIL and inter continental
stationse
S s use vk Slase sl slesi e o
The new call of Malcolm (VK7ZMS) is VK700 and can be heard on
HF as well as his usual VHF frequencies, his new 6M transverter
sounds real good. Don't forget to use that CW on VHF Malcolm.
o 0t ot
sicho sle
ae eR e
iRale ale ale als s ot s Al AU
R sk sk sk e ek
Joe VK7Z2GJ and myself (VK7JV) went to Hobart for the big sale
a couple of weeks ago and returned with quite a few goodies,
Joe's answer to the question "did you buy anything'" was
" oh about half of it"
ok e sl ol ofe sl sl e ok ool sk SRk
On the equipment store scene, Kevin is still doing his thing
and has amongst the usual items, ARRL handbooks (only a couple
left) printed circuit board, there are still a few pieces left,
available from both Kevin and John VK7JV, log books are again
in stock,.
sl e ok zk el sie sk sl ok sk ek
Don't forget your complaints about intruders still go to Harold
VKTNZ
Q.R.M November 1973
Page 3
NOTES FROM THE NORTH WEST BRANCH by VA&7MX
Thought provoker. Last month I struck oil. Thanks John.
Now to this month. Scout Jamboree on the air. At our meeting it
was reported that no official approach had been made to our branch
for any activity for the coming Jamboree.
A lenghty discussion ensued and it was agreed that the deadline
had passed and no involvement would take place this year,
In reviewing previous year's activities, members made many complaints
of shortcomings of scout groups.
Some have attended, some haven't and others were late. Many boys
sent along were unsuitable to broadcasting, it was a waste of time
putting them on the air. There were odd complaints of boys
intefering with apparatus also.
There appeared to be an attitude by odd leaders that the scouts
were offering the hams a privilege by attending.
On the constructive side 1t was suggested that in future,application
be made in writing to our branch for participation at least one
month ahead. Our branch would then at its next meeting allocate
groups 1f possible and arrange to visit groups and select suitable
persons to broadcast. It was pointed out that with sideband
apparatus only suitable voices are easy to copy and the uninitiated
will have difficulty in understanding what is coming over,
It will be interesting to hear views from other branches,
Our monthly meeting was better attended and we were pleased to
welcome Steve 7ZS5F and Robin 7RH from the North.,If nothing else
they certainly enjoyed a hearty laugh especially when the matter
of a couple of portable toilcts were discussed, very subtle wit.
Some suggestions were made for activities for future meetings and
it was decided that for the November mecting those that can bring
along a dozen colour slides and we will have a picture show.
Someone brightly suggested that a few "BLUE" slides would be welcome,
such as a slide gone wrong showing sky only,HlI., I have a feeling
that some art studies may turn up. There will be prizes given on
the night so turn up chaps.
There is a great deal of constructional work taking place in our
area, there is some HI FL, antennae and various gadgets, a healthy
sign.We are pleased to welcome to our group Nick 7NL from Smithton,
Nick is on HF and we now have regular skeds.
As soon as he gets the GS5RV up he will certainly be heard all over.
C.U.L MAX 7MX
Letter to the Editor.
Sir, as a regular listener to the w..i.A. Sunaay broadcast and to
sundry contests etc, 1 would like to suggest that the Institute
should attempt to persuade all members to use a standard phonetic
alphabet. The A.R.R.L. handbook suggests to its members to use
the International Civil Aviation Organization list which is used
by Australian armed services, Civil Defence Organizations and others.
It is quite common to hear an operator calling C.Q. and giving his
call sign with completely different phonetics each time he repeats it.
It should be the ambition of every operator to keep his operating
practice above reproach and standard phoneties should be included
in this. This may sound like'"stirring'but I would like to hear
any reactions to this suggestion,
73, Bob Jackson L70018
(A alpha R romeo Jackson)
QRM
BULLETIN O THE NORTERN BRANCH WIA TAS. NOV. 1973
Page &
_SummaryofAmsat-Uscar-B spacecraftsystem ( Oscar 7)
Amsat Deutschland Repeater ( designed by Karl Meinzer, DJ4XC)
1. Input freq. passband betueen 432.7125 and 432.175 lihz.
2. Output freq. passband between 145,975 and 145.925 lihz.
3. Power ouput ( high 1iode) is 14V PEP. .
4. Downlink passband ig inverted from the uplink passband.
( This means that USB input on 4%2 will comc out as LSB on
146. By doing this the max., doppler shift will be about “
9 khz., instcad of 18 khz., on a signal through the repeater.)
5. Repeater is 45% efficient using envelope elimination and
restoration technique.
6. Linear operation-- 58B and C¥ are preferred modes.
7. Repeater is commandable To either %.75 or 14VW PEP output.
8. Teclenetry beacon ai 145.980 Mhz,(200mi)
Ans%&mgyoflzgf”mfl_metrerepeaterx ( designed by Perry Klein,K3JTE)
1., Input freq., passband betwveen 145.85 and 145.95 Mhz,
2. Ousput freq. passhand between 29.40 and 29,50 Mhz,
( Eqipnent now being used for Oscar 6 will be usable but with
passband frequencies 50 khz, lower.)
3. rowvier output is 2y PEP.(this is lower than had been planned)
4, Downlink passband is not inverted from uplink passband. 3
5. Lincar oporatxon—-bB and CVW preferred modes.
6. Telemetry beacon at 29.50 ihz.(not the same as Oscar 6)
Morsecodo_telemetry_encoder(designed by John Goode, WUS5CAY) ®
1. 24 analog input channels,
2. Converts each analog value into a two digit morse code number.
3. A third digit precedes the telemetry value and gives the line
number in which the word is located.
4, Pormat is arranged 4 words per line,six lines per telemetry frame.
5. Moroe code telcmetry is commandable to 10wpm or 20wpm.
Teletypetelemetry oncoder(Peter Hammer,VK3%PI and £dwin Schoel VK3BDS)
1. 60 onalog input channels,
2. Converts cach analog channel to a three~digit number transmitted
in Baudot code.
3. Bach thrce-digit value is preceded by its channel number, making
a five-digit telemetry word.
4. the data is arranged 10 words per line by six lines per telemetry
frame.
5. Two lines ¢f status information follow the analog matrix and give
the spacecraft time(ie Time in counts from launch, 1 count
for every 96 minutes)
6. Output keys 435.1mMhs, beacon in F3K: 850 hz. shift;45 Baud;
( reversed from USA standard) Alsc keys 145.98 and 29, SO Whz,
beacons as AFSK on command.
435.1imhz,beacon transmlbtor ( Larry Kayser,VE3QB and B.Pepper,VE2AQ
1.” Beaconouput i1req. is435.1 mhz.
2. FPower output is 0.4% at an efficiency of 45%.
3. Beacon is FSK modulated 850-hz., shift.
2304Mhz., Smallbheacontranum1ffe“> ( San Bernardino Microwave Society)
1. 0.1 at 2304nihz ®
2., Turned on by oommand onlyfor 30 min. periods.
3. CW keyed--Hl followed by 30 sec. carrier. Also keyed with Morse
code telemetry on command.
Code-storc——iiessage
store-and~ forwvardsystem{ John Goode, W5CAY)
1.7 896 bitmemory capacitiy using
wOs/l0s ehift register memory.
2. Lioaded by command link.
3, Output code speed is 13 w.p.m.
Qo Re Mo November 1973
Page 5
THE CHARGING OF NI-CAD BATTERIES byVK7NR
In my occupation a lot of moans reach my ears concerning NI~CAD
batteries, personally I don't have any problems with them, the
main problem seems to be a lack of knowledge of these devices
by the user. | hope the following notes will help somebody who
might be thinking that he has lost hard earned cash in purchasing
NI-CADS., These notes have been compiled from manufacturers data
sheets and my own experiences, so if a trade name pops up now and
again please accept it in good faith,
General
features,
The average voltage of a NI-CAD is approx. 1.2 volts.
At normal discharge rates the characteristic is very nearly flat
until the cell approaches complete discharge.
The NI-~CAD provides most of its energy above 1,1 volt per cell.
If the cell is discharged with currents exceeding the RATED value,
however, the voliage characteristic will have more of a glope,
a lower end point voltage will be necegssary and the ampere-hours
per cycle will be reduced.
an91u81on.
Iverything is fine until terminal volts drop to 1.1 volt and then
hey presto a flat battery in a very short time.
The capacity rating of NI-CAUS is based upon output in discharge
at the 10 hour rate to an end point of 1.1 volt per cell.
I the currcent is dravn at faster rates than these standards
capacity is decreased. There is no simple way to determine the state
of charge of NI-CAD cells due to this flat characteristic.
Polarity reversal.
VVhere discharge is carried below 1.0 volt per cell a very rapid
fall to zero volts occurs. Because of slight differences in cell
capacity one cell may recach this point before the others and this
can result in cells reversing polarity.
Whilst polarity reversal causes no damage to sealed NI-CAD cells
when discharged at the 10 hour rate it should be avoided for
maximum life. After normal recharge a reversed cell will regain
its polariiy and function normaly.
Moral, try not to flatten NI-CADS,arrange to trickle charge
batteries durlng periocds when not in use.
Cycle life is at an optimum when over discharge is avoided,
recharging ls performed regularly and depth off discharge is left
as shallow as possible. But overcharging at elevated temperatures
should especially be avoided.,
When charge,discharge cycles are nearly full,life is measured in
hundreds of such cycles. When partial discharges are used,cycle
life maybe in the thousands. In rating cycle life,end of life
of the sealed NI-CAD cell is considered to be when it no longer
provides 80% of its ralod capacity.
Impedance
Sealed NL-CADS have a high effective capacitance, their impedance
igs so low that cells which are being continuously trickle charged
make excellent riple filters. Cell impedance is dependent upon
frequency and state of charge of the cello
Cellconnection. Nominal voltage of a NI-CAD cell is 1.2 volts,
toobtaina thhov voltage cells arc connccted in series.
When larger capacities are required a larger cell sizc should
be selected. Parallel connection of sealed NI-CADS should be
avoided,
Contactmaterial. Never attempt to solder directly to the cell
case asthe seals may be damaged by heat,
cont. page 7
Qs ReMe November 1973
Page 6
reprinted from "WESTLAKES RADIO CLUB" Newsletter
AERIALBALANCE MAKESSENSE
How many times have you seen the advice, "the dipole aerial has a feed impedance
of about 75 ohmse. This makes it a good match for 75 ohm coax".
Welly, if you want to be trapped, just go ahead and try ite It will work of course
but it won't work nearly so well as it should. After all, think about it for a
moments The dipole aerial is a balanced device but the coaxial cable, although it
has the same impedancey is unbalanced. Cuyrrents flow on the large outside conductor
quite differently from those flowing on the thin inner conductore
1T R
S RS AT : T SR
3 2 L B2 IRS TIo
UeSRR R T SRR AT 3 DA
= RSN
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rmreee
Losrmrm S Te e T
Orlglnal diagrams = "Electronics Australia”
That diagram you have just looked at contains the key to the situatione. The
drawings illustrate the electrical and physical intricacies of the balance to
unbalance transformers, known commonly as baluns.
These simple devices enable coax to be used to feed a dipole, because they match
the unbalanced load presented by the coax cable to the balanced load presented by
the acriale This set of conditions applies to the left hand diagram, showing the
1 ¢ 1 transformer, But baluns are not limited to only a 1 ¢ 1 transformatione.
The right hand diagram shows a 1 ¢ 4 transformation. This would be used where
the 75 ohm coaxial cable is used to feed a 300 ohm feedline = a 1 : 4 step upe
Remember yourtheory here- the .1 ¢ 2 ratio of the transformer as a turns ratio
results in a 1 : 4 ratio of impedance transformation. Since we are dealing with
impedance matching, then this is the ratio we use.
The details in the diaprams are probably quite sufficient to ensure that you
can wind your own balun but here are some tips on how the actual winding is dones.
You may use the stranded, PVC covered .'hookup" wire if you wish or ordinary
single strand PVC covered "jumper" or "bell" wire will doe However, it must be
“insulated,
The winding is accomplished on the 1 : 1 transformer by winding "Three=in=hand"
with, for convenience, threec wires with different coloured insulations. Thise
method is called "trifilar winding" to give it its correct title. The lengths of
wire for either of the transformers need be no longer than about50 cm which makes
them easy to handle when threading through the "eye" of the toroid on which they
they are wounds. The toroids, by the way, are the common type found in club projects
and they are about 34 mm outside diameter and made of Ol ferrite materiale. They
cost about 80 cents or sos The second diagram shows the method of "two=in=hand"
or "bifilar" winding necessary to make the 1 : 4 bhalune
Keeping the wires in place is no problem. They may be terminated on a tagstrip
to the formula shown in the diagrams ot they may be held in place while the whole
unit is buried in "Araldite" or "Plasti®=Bond" leaving flying leads for connectionse.
Whatever plan you use, your balun, suitable only for the HF bands though, should
give vou good matching between aerial and feedlinee
QeRoM. November 1973
Page 7
Final for the 6M SSB transverter by VK7ZGJ
POE0G[40
33bf 3Kv
/H%.‘f——”’~‘§T209 4730{: 2'D.1:5 long ouT
LN
Te 100" 1w
B2 MH=z
N y :
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S 20 4 L -
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= N 37204 684
LA 00 \(15
- S 100" 1w N
270?(]: , B 100
8 6 000y
— .
e
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-- 0o T
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47K 35V _5; ‘
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RLA +/2V
—100V 1
To TReceiver CONVERTER
N
cont. from page 5
Cells can be purchased with solder tabs fitted, if contact springs
are used they should be of nickle plated steel or stainless steel.
Copper and copper based alloys can cause local galvanic action
and subsequent corrosion and gshould be avoided.
Care and Storage. Do NOT short cicuit cells.
Cells are normally transported uncharged (manufacturer to buyer)
so if you buy a cell and it is flat you haven't been sold a
dud, CHARGE IT,
After prolonged storage and because of self discharge, the cell
will not have its normal capacity, but this will be regained by
2 or 3% cycles of charge and discharge.
_NEXT MONTH
THE CHARGING OF NI-CADS.
QoRo M, November 1975
Page 8
POWER SUPPLY FOR THE 6M SSB TRANSVERTER by VK7ZGJ
1000V /A
St Fy
240V
+/2V
500 12V’ "[s00mfd CoNVERTER
£M4
4 01 - ——OV
AT e
so0 10V [S00mf
LIDERAND exarTer (FL200)
- PrT.T.
- .q"b.'
0 |
f—_— V = T
Rerial ¢fo
Al Bypass
1000 pf
F--1
The Tasmanian Division
JUBILEE HAMFEST REGISTRATION FORM
celebrating the
50th ANNIVERSARY
of the division Name VK
at EVANDALE
over weekend 24th and 25th
November, 1973 Address
Refreshments, Fox Hunts, Films
Camping Facilities
Cheque enclosed for
VHF ‘Talk in' Facilities Accomodation required yes / no
Car Phone Checks, Dinner
and other activities Registration Fees :-
WIA Broadcasts or both days Double $5, Single $3-50
VK7 Northern Branch . Student $2~50
Box 1010, Launceston, 7250 Sunday only $1-00 per adult,
Qe Ro Mo November 1973
Page 9
ATTENUATED SIGNAL SOURCE (for 2 mx.)--Basil Barnes, VE6BB
The idea for this one comes from a couple of KICLL's articles in 73
magazine. Being an invetearate '"fiddler" and always trying to push
just a little more out of both transmitters and receivers, | found
that | needed a means of comparison. For receivers this meant that
I needed a stable signal source, modulated preferably, and infinitely
attenuable. As well, the attenuation had to be smooth, rather than
be switched in jumps (i.e. 1| db, 5 db, 10 db, etc.)
The signal source is easy for anybody who has read this far. All
you need is your transmitter crystal and a l-transistor oscillator.
To modulate it all one neegs is a l-transistor phase-shift oscill-
ator which modulates the B to the crystal oscillator.
I't is the attenuation that appears to be difficult. After all it
costs a lot in commercial signal generators, doesn't it? Here,
however, we can avoid the cost by not having to calibrate the signal.
All that we need is a piece of thinwall pipe about 20" long, and
about 2" diameter. I use copper myseif, but any metal will do. For
one end | prepared a disc of metal (copper again for me) that just
fitted in the end of the pipe, and in the centre of this | fastened
a BNC connector. To the inside of the BNC connector | soldered a
small disc of metal (copper), which was parallel to the larger disc;
and here a diagram would be in order:
_______ o Swe Enp O Large oisc Just FiTs yre o
View vigwW
Srank PSS g A’j Beac Piec
i" T O
This is soldered to one end of the pipe (see why | used copper?),
with the disc inside.
The oscillator and the modulator are built onto a small PC board
such that the completed board will fit into the 2' pipe, and the
whole lot is attached onto a narrow strip of board that will slide
in and out of the 2'" pipe. The output of the oscillator is fed
to another disc the same size as the one soldered onto the BNC
connector, and this is fixed so that it, too, is parallel to the
end disc. The battery and switch is also fixed onto the board--
AND HERE MAKE SURE THAT NOTHING METALLIC COMES OUT OF THE PIPE
WHEN THE BOARD IS FULLY INSERTED INTO THE PIPE! Here another
diagram would be in order:
Opx Yo
ol
T Boare Witk O5SGLLATOA b s {/9
Pee?
Ruul:{ SWiTen ~ And MoDULATOR .
5 e
CP
- =T ==
B ie et N -
A e .
)
el 0 [ L
lapadetatatals
- e W o s = -
\‘i- e
8A1ranw
Now, when the slide is pushed all the way in, the two discs touch
and you get maximum signal transfer through to the BNC connector
(and the receiver). As the slide is slowly pulled out the signal
attenuvates smoothly until it completely disappears. By using this
you can peak up preamplifiers, see the effects of changes made in
RF circuits, and optimally design new preamps. I glued a ruler on
to the slide so that when the two discs were touching the ruler
indicated 0", and as the slide attenuated out, the distance showed
the separation between the two discs. I can never hear anything
past 3" on my Attenuated Signal Source {(and | will NOT abbreviate
that!) For those interested 1'11 give the schematic over the page.
QeRo M. November 1973
Page 10
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. 4 #ie 4 T
¢ . Ty ¢00RWED FOR mE
WITr VEARY (TyLg WORK.
16K 1 Feg. ¢RE6 To ABIus<
S ..}, ! VT To Swiv YouRSG(E.
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Q)l =z Semall i'ijr\oJ
YECRE ViE hype e.q. 285132 ek,
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A_MODIFIED OSCILLATOR FOR THE VK3 V.H.F. GROUP 2-METRE CONVERTER
Difficulty has been experiencsd with the FET overtome oscillator. The trouble
usually manifests itself in one of two ways: 1. Complete lack of oscillation, indicated
by very low noise output, inability to receive very strong 2 metre signals and absence of
spurious unstable signals in the output tuning range. 2. Spurious osci&illation, indicated
by spurious signals in the tuning range, a very rough ncte on receive signals and/or
frequency instability.
It is n sad fact that there is considerable variation in characteristics between
individual overtone crystals. It is equally sad that some crystals are simply not capable of
operating correctly in the original circuit, shown in Fig.l . In such cases the use of the
oscillator circuit shown in Fig. 2 will usuzlly overcome the problem.
N\
i
e
e % 368k
5 PNRSHE |
LR
o =, = I o _, ORIGINAL
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The particular circuit can be accommodated on the board with the minimum of butchery
Na copper &ma runs need be cut. L5 becomes superfluous but for appesrances the can can ke
retained if desired. The drain collector circuitry remains unchanged, as does the frequency
pulling coil L7. )
With this oscillator circuit the converter should operate f rom switch on as oscill- ~
ation occurrs regardless of collector tuning. Output is somewhat higher than with the FET :
ggg&%l?tgr, and with broadecasts IF's , desentisation can occur. Noise figure is degraded to
*“dB. With Intermediate frequencies above 3.5MHz this problem does not occur.
The orginial circuit was designed for multiplication by 3. The modified circuit can
he *7L.! usedwith times 4 multiplication of crystels in the 30 MHz range.
¥ Acknowledgment to Victorian V.H.Fer and Bob Halligan, VK3AOT.
e
Q@
SOLID STATE
.
.0 KITS
2 RECEIVER: 20 db quieting at .3 Micro volt signal, Mosfet front end, I.C's used in
I.F. and audio Price $61.20 alone $55.20 in Transceiver kit
EXCITER: 1 Watt RF output. Suitable for driving a valve Final or our 12 W
Transistor Final, Price $18.98
“DEECH AMPLIFIER: Constant level output. Best suited to a Crystal or Ceramic Mic,
Price $13.80
XTal BOARD: 5 Channel manual switching with Xlal frequency adjustment. Price $10.35
or
SEARCH OSCILLATOR: This scans 4 Channels and locks Receiver to a signal. L.E,D's to
show which channel available if required as an extra, Price $25.00
CASE: Includes Speaker, Knobs, Sockets for R.F. & Mic,
Price - Deluxe $24.95 Standard $18.98
R.F. AMPLIFIERS: 3 W $10.43 10 W $28.00 12 W $37.95
Wired & Tested
CONVERTERS: 430 MHZ $17.35 2 Metre $14.00 6 Metre $14.00
2 AMP regulated power supply will operate any 12 V Transceiver, etc., or
Charge Batteries ‘ Price $32.00 Assembled.
2 Meter pre-amplifier $5.61
10 - 15 - 20 Metre Tunable pre-selector $18.00
1 W Kit. Standard case $117.31
All kits operate on +12 VDC and are guaranteed if correctly assembled.
GIPPSLAND TRANSCEIVERS
TASMANIAN AGENTS
NORTHERN BRANCH W.I.A. TAS. DIV.
PO BOX 1010 LAUNCESTON TAS. 7250
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J&T. GUNN PTY. LTD.
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50 Brisbane Street,lLaunceston. o
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Telephone 2 2251
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DOMESTIC & BUILDERS HARDWARE
MARINE & PLUMBING SUPPLIES
PATNT & TOOLS
SEDDON PRESS
35A GRANVILLE STREET, LAUNCESTON. 7250
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Telephone 31 6191
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for all your printing
Business and Personal
QST cardsg *¥¥x
NORWINg
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FLECTRICAL ENGINEERS
SPECIALIEING IN MOTOR REWINDING AND ASSOCIATED WORK
27 SUNCREST PLACE, RAVENSWOOD
TELEPHONE 391515
Athol Lawes Electrics
3
135 HOBART ROAD,
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KINGS MRADOWS, LAUNCESTON =e
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Telephone 443119
TRY US TOR YOUR NEXT APFILIANCE
YOU WILL FIND IT EASY ON YOUR POCKET $ § &