QRM
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£JLLEIIN ISSUED 5Y THE NCRTHERY ZONES OF THE P.0,BOX 1010,
WIRELESS INSTITUTE OF AUSTRALIA TASMANIA DIVISION LAUN CESTON ,
(3
TAS, 7250,
NOVEMEER
VOL. 1 NC. 7/
oe e .S e .i 4
EGISTERED AT G.P.0. HCBART
&=
e
or hrrns*ssiou by dost as
2 Pericdical, CATEGORY B, - PRICE 5¢.
©
Yoot readers of QR and WIA Bulletin will recell reading in the last issucs
£ the neu(‘lnL sale of gear owned by Mr, Len Crocks VK7BQ who incidently, is Patren
#d TEPe ovber of the Tas. Division of the W,I,A, Vhat therefore could be a
nore fitteog time to rause for a monent to reflect on Radic as it was when Len
sornanced epcratien back in 925,
Troly, vhey were the great days, hard but terribly intercsting, when the
;-
marie veltaos wes largery dependent ¢n the nunber of rarrite jars you could scrounge
e
a1’ you put brackets cn the smek wall tc held yecur Tank ccil so you didn't OSY
cveryline soraene walked inte the shack and it wasn't uncorron te sce tubcs with
their-ceses reroved for greater efficiency, “These cccasions were corron place when.
Len firet got cn the air. I can recell Len winning a prizc for the best hone-built
rcceiverf ia an cxhibiticn in Launcesten, of which the front pancl was glass.
migine the clfort 1nwlved In drilling all the holes, nc Qrgumcnts in those
ays Letueen uasers of cormercial and hone brew eouipment. If you cculdn't afferd
"1:'3' 1istlc was ofrering veu maco it, This encouraged visits between hams as the
varicus rmerbeors of the fretemity went locking for ideas and discussed their
. conblens wilh onc encther and the nerery cf these get-tcgethers is scmething
b
cvery cld~tiner will roererber as long as he lives, If you den't think so ask
Len nexs time youa sce hin,
Yes, tho#c were the young days of 7BQ; the cdays when Len put a recorcded
srograrme cn the air on 200 etr\,q cvery Sunc ay rorning bcfore we had any
“wadenst stationsin the Nerth of the Island and I can assure you the quality
end presentation of the prograrres were excellent and rerenbercd by neny of
the oldcer citizens of Launcesten to this day,
Len prosresscd through these pericds dewn to the early days of 50 Mes
felicwed by 144 and 432 Mes end later tc M gecar. Unfertunately age was taking
its t011 andyto tho ggxoat regret of cveryone,Len madc a big decisiony he would
~ctl all his gear.. On Saturday rorning at 10 o'clock he made his last broad-
a8t te his con Jolm VKBAAC whilst the crowd gathered cutside waiting fcr the
sule o comrence, It is with great pleasure that we can announce that it
was a huge succcss and the sun of %$250.00 was raised,
For some reason or other scre gear still remained in the shack together
we D the GSL's en the well reminding us of days gene by, Strangely encugh
thie pear included a 40 netre transritter, a rodulator and associated power
enpnlifes, se you haven' heard the last of 7BQ yet which goes to show you how
wr g we wers,
At 81 ycars 7BQ is still with us and we hope it will stay that way for a
lozp dine,
Vv To ;oou Len ~ GOOD LUCK, COCD HEALTH end MANY MANY MORE HAPPY DAYS!
COL, 7LZ.
T4
sw——
36363636
63 336343¢
COMINGEVINTS
P, - B W SNl = TN =MUAE T| R R =
. ¥ O o . TT
REGISTERED AT G,P.0. HCOBART
fo; tremsmissicn by Host as 7
a Pericdical, CATEGORY B, - PRICE 5¢.
e i o ee e e
Mot ceaders of QRM and WIA Bulletin will recell reading in the last issues
¢f the hendlng) sale of i gear owed by Mr, Len Crocks VK7BQ who incidently, is Patren
end Tifle ifebcr cf the Tas, Division of the W.I,A. Vhat therefore could be a
Lo ref‘ltt, _ne to rause for a morent to reflect on Radio as it was when Len
aormsnced ¢ wcmuk n back in 9258,
. w1y, they were the great days, hard but terribly interesting, when the
maenbe velbacs wes largely dopendentcn the number of marrdite jars you cculd scrounge
[
a1’ vou pat brackets on the saack wall to heold ycur Tank coil so you didn't GSY
cverytine soriene walked into the shack and it wasn't uncorron te sce tubes with
taeir-ceses reroved f‘or greater efficiency, These cccasions were corron place when
Lea firet got en the air. I can recall Len winning a prizc for the best hone-built
rcceiver. in =n u:ch"xbiticr in Launceston, of which the front pancl was glass, |
Im:ginc fhe cifort 1nvolved In drilling all the holes, nc argurknts in those i
days Letween users of cormercial end hore brew ec»ulpment If you cculdn't afford
wvhat 1ittic was offering veu mace it., This encouraged visits between hams as the
varicus members of the fretermity went lecking for idcas and discussed their
)
: »inblems wilh cnoe ancther and the mereory cof these get-tegethers is scnething
€ b ——
cvery cld-tirer will rererber as long as he lives, If you don't think so ask
Len nexrt tire you sce hin,
Yes, thosc were the young days of 7BQ; the cdays when Len put a recorded
nrograrme cn the air on 200 retres every Sunr ay rorning bcforc we had any
Eroadeast stations in the Nerth of the Island and I can assure you the quality
gid presentation of the prograrres were excellent and rerenbercd by neny of
the older citizens of Launceston to this day,
Len prorresscd through these pericds down to the early deys of 50 Mes
Tellowed by 14, and 432 Mes and later tc BM gecar, Unfortunately age was taking
its t1l and,to thc great regret of ovoryone,Len madc a big dccisiony; he would
~c!l 21l his gear. On Saturday rorming at 10 c'cleck he made his last broade
cast te his cen Jolm VK3AAC whilst the crowd gathered cutside waiting fer the
sule o commence, It is with great pleasure that we can anncunce that it
was a huge success and the sun of %250,00 was raised,
Fer sone reason or other scre gear still remained in the shack together
we ot the GSlL's cn the well rerinding us of days gene by, Strangely encugh
this gear included a AD retre transritter, a rodulater and associated power
enpliies, sc yoeu haven' heard the last of 7BQ yet which gees to shew you how
wLOT.E Ve wera,
At 81 ycars 7BQ is still with us and we hope it will stay that way for a
locg wine,
v To ou Len .. GOCD LUCK, CCCD HEALTH and MAYY MANY MORE HAPPY DAYS!
ooL, 7LZ.
33K
COMING EVENTS
NCV, 2nd WORTH WEST MEETING, Lakin's Hall, Ulverstone
s -NOV. 12th NORTHERN 2z(NE MEETING, A.E.B. Rooms, 8 Eligh Streot,
Launceston,
NOV, 27th -~ 28th 1A FEST,
QRM
BULLETIN OF NORTHERY ZCNES W, I, A, TAS, NOVEBER, 1971,
PAGE 2,
THE NORTHER! ZONE necting held on October 8th was attended by 36 rembers,
Visitors and ncw faces included Mex 7MX anc Ed, 7HE,
Arongst the inwerd rail was a letter frem our Statc Intrucer Watch Co~
ordinator Ian 7KB and rembers were pleasced with the renort forms included (let's
hepe they all get returned full of info.)
Peter 7PF reported that cverything peinted tcwards e license for the repeater
being forthecoming in the ncar future,
Approaches madce for Jemborec on the eir participation were detailed, Threc
groups had requcsted help end this had been organised but more opcraters were
re ired, A Fox Hunt was orgenised for Octeber 22nd, It was suggested that
fuither orders be taken for name badges, (If you nced one contact Kevin '7Zz‘3‘H).
After the mecting closced at 9,45 Den 7DK gave a very intercsting talk and
prescnted a very well »ut togcther colcur film of his recent 16,000 rile trip
around Australie,
If we arc able to use the right room at the next meeting, Rex 7RB will give
a lecture on Audio end distortion, Don't miss cut on this onc chapsi
336363 I NK
Fe A IHK
PERHAPS thc nurnbcr onc event on the VK7 Han Calender is cn the doorstep -
THE HAMFEST, Why is it of this irportan ce.f It's thec only time when amateurs
from all over the statc can get to sce cach other for morc than an hour or twe,
Conventions anc Hanfests arc an important cvent to amatours intcrstate and
overseas, If they think then such fun vhy arc you going to riss out.? It scems
that a group of amateurs fron intcrstate arc likcly to come including Federal
President, Michacl Owen,
To come along is onc thing; to participatc is cven rorc imoertant.
What'!s nceded te participate — in order of Cifficulty:
(e) a shortwave transistor o
(b) a car
(c) a transistor sniffer
2 Rl 3 rmtr heam EM 0T T A
Masanlhan
(\'1\ a
hope they all get returned full of info.)
Pcter 7PF reported that cverything peinted tocwards a license for the repeater
being forthecoming in the ncar future,
Approaches made for Jarborec on the eir participation werce cdetailed, Threc
groups had requcsted help end this had been organised but rore opcraters were
s irved, A Fox Hunt was organised for Octeber 22nd, It was suggested that
further orders be taken for name badges, (If you nced one centact Kevin ’7Z;"§H) .
After the mecting closcd at 9,45 Den 7DK gave a very intercsting telk and
presented a very well »ut together colcur film of his recent 16,000 milc trip
around Australiea,
If we arc able to use the right room at the next nceting, Rex 7RB will give
a lecture on Audio end distortion, Don't riss out on this onc chapsi
FHH I HRHNRHK
eI INH
PERHAPS the nurber one event on thce VK7 Hanm Calendcr is cn the doorstep -
THE HAMFEST, Why is it of this importancof It's thc only time when armateurs
from all over the statc can get to sce each other for rorc than an heur cr twe,
Conventions and Hanfests arc an important cvent to amateurs intecrstate and
ovcrseas, If they think then such fun why arc you going to riss out.? It scems
that a group of amateurs freon intcrstate arc likely to come including Federel
President, Michacl Owen,
To come along is one thing; to participatc is cven rorc imortant,
What'!s nceded te participatc — in order of difficulty:
(2) a shortwave transistor i
(b) a car
(c) a transistor sniffer
() a 3 El, & mtr, bean #™ CH,B Carphone
I believe cne well 'mown identity built a sniffer and cot it zeing in
30 minutes ~ try it., The Hamfest will be ruch more fun !¢
REG. 7KK,
QRM
BULLETIN OF NORTHER' ZCONES, W.I.A, TAS, NMOVEMBER, 1971,
PAGE 3
VORTH. WESTERN ZONE
Last neeting was well attencded with a number of young people present and
we hepe these boys will continue to come, John 7JV and also Robin Harweod were
present from Launceston, We alsc welcened a new licensee, Graham Sirpson, Cone-
gratulations Grahen and hope to hear you on the band scen,
Yow the apclogies revcaled scne interesting humen drena, Teny 7AX was in
Hobart, working hc maintains, Brian 7ZBE was ceeply involved in something irmortar
Athcl 7LR was involved in ESP or was it EDP, Bob 7ZCGR was on tirme and a half or
double perhaps, Les 7LH ran foul of a dentist anc hacd a jaw to »rove it, We
wrote down John Webster's name and had to scratch it out, because when we locked
he was there complete with harreonic who appears to b<;> teaching Dad scme finer
points ¢f Radic.
Ken 7KH ably chaired the reeting,
Asscciate Reg, Pclden was present, Ve appreciate your regular attendamce
Reg. Johl 7JV brcught us up to date with Institute natters, Tan 7KB was present
and npresented scme pointers to help us to log intruder stations, Scre log forms
were distributed and renbers are asked to return them next reeting,
Devid ™S becare involved with Marilyn M, sorchew or was it current loops
of 2 half waves in phase, Cenfusing,
We are pleased to welcorc Charlie 7CF back tc the HF ban@s. CGood to hca
cld tiners again,
We remind our rmerbers - if ycu haven't registered for the Hamfest - do
so urgently, You might just rake it,
The writer had the pleasure of attending the last reeting of the Northemn
Zene, Well attended, well ccnducted and I really felt at hore, At the conclusion
of business Den 7DK presented the hest amateur travalogue I have seen, Den, we
would love to see you cerplete with map and filn at a N.W, Zene reeting, Pleasc
accept this as a perscnel invitation.
Seturday rorning of the 9th found me at the QTH of 7B(, where a sele was
taling place, Sone very fortunate pecnle carc away with home brew geer of a
very high order,
Mow the apclogies rewcaled scne interesting human drana, Teny 7AX was in
Hobart, working he maintains, Brian 7ZBE was ceeply involved in something irmortar
Athel 7LR was involved in ESP or was it EDP, Bob 7ZGR was on tire and a half or
double perhaps, Les 7LH ran foul of a dentist ancd had a jaw to prove it, We
wrote down John Webster's name and had to scratch it out, because when we locked
he was there complete with harrenic who appears to be teaching Dad scrme finer
points ¢f Radic,
| Ken 7KH ably chaired the reeting,
Associate Reg. Pclden was present, Ve appreciate your resular attencdeamce
Reg, Johm 7JV breought us up to date with Institute natters, Ian 7KB was present
anc presented scrme pointers to help us to log intruder stations. Seme log forms
were distributed and renbers are asked to return them next reeting,
David 7MS becare involved with Marilyn M. sorchew or was it current loops
of 2 half waves in phasc, Cenfusing,
We are pleased to welcore Charlie 7CF back to the HF bands. Cood to hear
old tiners again,
We remind our merbers - 1f ycu haven't registered for the Hamfest - do
so urgently., You night just rake it.
The writer had the pleasure of attending the last reeting of the Northemn
Zene, Well attended, well ccnducted and I really felt at here, At the conclusion
cf business Den 7DK presented the hest amateur travalogue I have seen, Den, we
would love te see you cerplete with map and film at a N.W., Zone reeting, Pleasc
accept this as a perscnal invitation.
Seturday rorning of the 9th found me at the QTH of 7B0, where a sele was
telsing place. Sone very fortunate pecple carc away with hore brew gear of a
very high order,
We wish you the best of luck Len in your ncw envirénment.
Sec you next ronth, MAax T Mx
CLOSED CIRCUIT
?Rccessmq COMTOSITE
A, MomiToR
Atove is scric of the basic gear required for en A, T.V, closcd circuit set
up. As rentioned »nrevicusly, the hcart of any systen is the syne, pulse
generator (S.P.G.) The S,P,G. generates the horizental and vertical sync, pulscs
together with blanking and cquelising pulses, These pulses arc then fed to
the F.S.S., (Flying snot scanner), live cancra, or tcsting generators ete,
Thesce pulses are uscd to syncrenise the cscillators (herizental and vertical)
and provide blanking. The video producing cquiprient cen then be sclected by
nanusl switching or all used together sirultanccusly., The video produced is
passcd to a processing ammlifier, The purpose of this arplificr is to combine
the video with sync., end blanking pulses te the corrcet nroporticns, The
cutput from this proccssing arp, is known as compeosite video (i.e, all vision
and sync, ete, necessary to producc a telcvision picture less the scund), This
ccrposite video i1s then fed inte cnc or several roniters,
At this stage you arc probably wendering abcut the varicus standards to
usc, there are nany argurents about thesc, however it is rnyopinion that the
answer so fer as Australien A,T.V, is ccncerned, is to use the 625 line systen
frem the start, The lower frecquency linc systoms do have sone adventages,
including narrower bandwidth, This I fcel can still be cutweighed by the
irproverent in definition cbtained frem the 625 line system, and the fact
that our lowest frequency for transmission of videco is 420-450 MHZ bend,
6 MHZ bandwidth is not toc hard to achicve at this freouency,
Sccondly the usc of 625 cnables us to use a standard TV receiver modified
slightly for usec as a ronitor, A switch arrangercnt on the receiver can be
wired to allow cither the nermal IF of the receiver through tc the video aip,
or the cerpesite videe from our systen as required, Morc abeut this in a
later article.
Having achicved a closced cet, systen and being satisficd with sare, it
is cnly a relatively sirmle ratter te feed the cerposite video te a special
ty-e of rmodulater end thence te a U,H,F, transritter,
Next tine T hope te cutline a 1ittle on the receiving of A, T.V,
TONY. (VK7AX)
SOME_FUNDAMEN TAL,POINTSABOUT R, F, TR/AVSMISSION LINVES,
One of the main objectives of a trensmission line, ie to trensfer RF
cnergy from a generator (transmitter) to a lead (aerial)
WHAT A TRANSHISSION LINE LOOKS LIKE:
L L LY L
- o—-m’W
éj'\[/—>imm7w._|_~mflfmj;—fflm\l—‘
Incductance end capacitance present in a line,
n nfinite number of shunt capacitance, scries inductence, and
resistonce scetions having
O a CHIARACTERISTIC ILHDEDIJ\’ CE QR SURGE IMPEDAN CE (20)
o ,/‘L = (HENRIES
7 = N TC = (FmaRans
The characteristic iipedance (20) is a function of wirc diarcter anc
“pacing NOT ireguancy: the characteristic irpedance will rernain constant
repavdless of frequency,
70 for cpen 1lincs
7= 176 Loc
70 for ccaxial cablc °°
20= 138 log,
d
If a transrissicn linc is used to transrit RF encrgy fren the generater
the load, the linc must be terminated at cach end (with a resistive load)
te awa.lue cguel tc the valuc of 70,
e.2Z. Z0 = 50 chn,
T
e _______7v_—____.___.-—.._..__‘___.___~,._._1<
eete e e is ettt ot oAttapesen]
{
6_ | z0= 50 j'5o S
?Luflb
’-'—!——'—1 e e
ee ete e et oot e et eytttst
BT
l,u/g \r\Tot\
Z oz 50
If o transimissicn linc cof finitc longth is terminated in resistance
cguael to its 70, the linc will, rcgardlcss of lcngth)flcz'bnstrate all the
propertics of the infinitely long linc,
Applying R.F, cnergy to-the input of the linc willresult in, (
field surrounding each conducter, (b) an electric field between the tieo
these two. fields eppéer at right angles to cach other and the ecnmbinatien ,
an electrcnagnetic field. The electronagnetic ficld roves in cne cdirectionm -
is frcn the gen(-arator'towards the load,
//, ;} FREE LZbCTIZDP-S
i
| - /
y (
“
=
/ ilEeTric Lines oF Forcee
o=
=N
“‘i"’/) MAGNETIC LiNES oF FortE
L /
N
Ihc ceTgyad'vanccs towards the leoad as an elecfimnagnetic field,
NEXT MCNTH: Hlectricai wawelengthy Velocity of propagation; Terrinating a lineg
Rescriant lraas**:_Sblcn lines.
VK7TB,
Fe IR
NK
UT, BARLCW 2 METRE REPEATER VK7WI/RZ
Tris repceier ls now liceased ard operating cn channel 4, 146.4 mhz input
and 45,9 rhz cut., This is cnliy 2 terperary frequencypeiruntil a nroposed Australia
_wide re—organisaticn cf frequencies has been finaliscd, The change back to channel
J, was mace fo enable these staticns elrealy fitted with crystals tc make usc cf
the repeater wntil o final channel is sclected, This cculd be the old chennel 1 i
input of 146.1 vhaz mfl, output 500 khz higher at 146.6 rhz, but nothing definite ‘
has been Jecided te date, Staticns no b £itted with Ch, 4 shculd held off buying
crystals till 'bhin.;;'s arc settled, ’ 3
The repcater will open up a new reans of reliable comrunication cver a wide
arca end this wide coverage rust be considerced during its use,
Do not hrra the channel, allew for other staticns to breek in and go te
encther channol if possible for thesc long rag--chews,
Mobile te rebile contects will make up rost of the contacts in deylight
houre with fixed =taticn cperaticn at night., I believe this fixed staticn cperaticn
vill do wuch te bring tegetier cperaters in the different centres, cspecially the
7 c211s whe do not have the use cf HF fer this purpose,
I, as slaticm nerinee beeere respensible for any irproner Cfleratlon of
Tl reneater be it technical or by the pcople using it., De use all of your call
~8imm cr nct at eil (you have five rinutes), Watch what you say, being on VHF
yeu nay have becene used to being heard a few riles instead ¢f the 100 or so
you may be heard now, Den't believe that because VK3s dc it that you cen get
awey with peer cperating, thb‘, arc finding cut ncw that they can't either,
In the advent that I hcar immreper cperaticn, it cculd be e pirate, I will have
te tum the repeefer olt. I heoe this will never be necessary and VK7s will
shew how chw' can vpcratt, anc. sharc a cormen frequency,
I wiil aporecicie olsc any infermation on any tcchnical problemss preoblens
in Jdifferent arcas and with the repeater iteclf, Mest of the bugs have been
scried out but due te the monitering systcm the repeater cculd shut dewn withcut
any apparent reoscn tc the listemer, We will have to put up with any incénvenience
causcd by this, becausc withcuv the built in safcguards, we wouldn't have a
repeater, '
Sc there it 1@, cn the air at last aftcr what arcunts te abcut feur
years of cxperinemtbing end work by rysclf, 7KW, 7ZRF, 7PD and cthers,
VK7PF,
EQUIPMENT STORES
CCIT TACT XEVIN HENRICKS, 8 Clarenden St. Youngtown,
PHONE - Heme 46 9772 or Werk 32 1208,
213055 1.60 ea.
2 3563 0.60¢ "
21356/, 0.60¢
AT 3565 0.,50¢ "
SE1001 0.30¢ "
¥PF121 MCSFET 0,50¢ "
AT140 MCSFET 1.90
A15245T1583JFET 0,95¢ "
213810 JFET 0,70¢ ©
1i61550G 1.C. R.F, I.F, AP, 1,30 ea,
IM37C0 I.0. Audic Scuclch & A,G.C. $4.00 ca,
Ri08 DTODE 800 P.I.V. 1 amp. 0.50¢ "
10 YFD 65 VW Non Pclarised Capacitors,10¢ "
SV Zener Dicdes, 340 mw 0.,50¢ M
470 PF Dutton Bypasscs 0.50¢ "
0,7-6 PT Trirmers Ccraric Oe4R25¢ M
1.5-9 PF PIFE Trirrers 0.25¢ "
1.5-12 P¥F PTFE Trirners 0425¢ "
NECSTD FORMERS 0.,05¢ "
SLUGS F29 and F6 0,04¢ "
SINGLE C/ANS : 0,07¢ "
DOUTLE CANS 0,08 "
T4, SOCKETS D type for P.C.B. 0.20¢ "
PACK OF 4 VALVES 1-.64X5 2.6AU6
2-6BAG $1,00 "
B/Lee Ceax Scckets for P,C,B. 0e25¢ "
RESISTORS 4W Individual Valucs 0,04¢ "
Retays L Chenge over centacts
12V Miniture $2,50 "
Socket for Relay Oo45¢ "
B/Lce standard sockets 0.35¢ " P.C,B, TYPE 0,25¢ ca,
B/Lce Alun, Plugs 0.30¢ "
W.I.,A, Car Transfer O.15¢ "
(OSL Stickers, Sheet of 40 0.50¢ "
T.C.A, 167/ Circuits 0,50¢ "
Hendbocks AWA MR-20B BM Corphene 0.50¢ "
Call Bocks 1971 0.50¢ "
Log Bocks and Air Dux Coils
WIA TIES Blue or Marcon
Full Mcrbers only $2.75
TIE BARS (GCLD) with WIA Badge
Full Merbers only $1.60
PRINTED CIRCULIT BCARD 10"XAHM 0.50¢ "
10 PCTRYTIOMETERS Various Valucs $1,00 "
ELECTROL.YTIC CAPACITORS
220 MF .. 16 Volt 0.20¢ "
100 IiF — 10 Velt 0.15¢ "
25 UF - 25 Volt 0.15¢ "
.001 CERAMIC 500 Volt 0.,05¢ "
THE FOLLOWITG ITEMS ARE AVAILABLE CN ORDER CNLY
50 ohn Durmy Load-Wattrmeter Kit $3.20
M VK3 Cenvertcrs Vew Price $10.58
2M VK3 Prc [MP mooom “/s 86
ALT, RSGB AND ARRL PUBLICATICNS