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TASMANIAN DIVI S ION
SEPTEMBER 1965. BOX 85-1 J, &oP. O., HOBAET
M 0 NT I: LY BULLETIN PRICE 6d.
PRESIDENT: Mr. T. Alien ™^ASTO^: Mr. V. ?. Bore SECRETARY: Mr. K. Spiegel
VK7AL VK7.7D YK7KS
Registered, at &, P. O., Hobar-b, for transmission by post as a periodical.
EDITORIAL
Another Remeffi ;brance Day Contest has passed by and all Divisions will be weighing
up the evidence -fco determine the winnero
To the younger Amateur v/ho did not par-fcicipate in the Second World Wary -to
generali-se, wculd no-b view the R. S. in the same light as one cf the older fra-berni-fcy
who dido I would venture tc say -that the former would hovrever, on con-fcemplation, feel
-by o'bser^a+.ion lih&t this Con-test. has something which depicts that part of -the " Amateur
Code " which says -bhe Aina-teirr is Gen-tlemanly o To listen to -the majority of the contest -
ants, who, under adverse listening condi-tions, go to no end of bc-fcher -tc ensure the other
chap has -bhe necessary informativ j-flo I know that the cynics will say,
"
Of course he will,
+, o get the eeore " however; -bo lis-ben further one hears acknowledgemen-fc of pa-tience e-tc,,
plus chit cha-t which would denot. e t. hat a high score is not everything,,
The point of -the ma-t-ter is that. if -bhe R. D, does teach us -to be friendly and consid
era-be of others, t. hen -fchcae v<ho gave -bheir lives did no-t in vain, le-t we and others
prosper from these good manners - L^st. V7E Forget.,
Meetin s for Sept'ember
•September J North West-ern Zones Lakin's Hall, Ulvers-bone. 2000 hours
??OT^-ham^a-K* ^ TTo arl ^n n-n4-/'>. ->^-^ P-^v'l^^^^·-l^ Tt/T^/^4-^wi n> -1 / T T^^^^^^/^/^T0-I. TT^T- _^^. r^r\r\r\ i_ „ ..
The Monthly Bulletin of -the Wireless Insti-fcu-te of Australia
Pa e 2
September 16 . . Tasmanian Division.
John Mo Ie Memorial Na-fcional Field D Contest; Resul-fcs_
Award IVinners
Section A ( Portable Phone )
VK15B S. F. Brown 484 poin.'fcs
VK2ASZ RoLo Lear 583 points
VK3ZRY B.. L° Harrison 280
VK4KZ : ^R.M. Fee.nagfh-by 925..
VK5TH ,.....-. T.. Mi-fcchell- 186 T1
W.6MS. MoJo McDonald 162 11
VIC9XI Do Reed. 104 11
SECTION B ( Portable G. W, )
VK1SB 3. E. Brown 152
VK2JM J. A, Mead. 130-
"VE5ZF I. L. O'Sonnell 318
VIC9XI . D« Reed 24
SEGTIOU C ( Por-fea'ble Multi - Op )
VK1AGA Canberra Radio Socie-ty 901
VK2BVi1 VoH. Fo & T. V. Group of the
N. S»V'/o. Division of -the V^I. A.o 1176
\?K3ATO W. IoG. S. K. Sta.-ti.on of. VE3 1648 1»
VK5TM . R. D; Martin 800 11
W. 6W Vfes-b Aust. ' VHP Group Inc.. 410 II
SECTION D ( Fixed S-fcations )
VE1LF L. B. Fisher 195 II
VK2 APK DoFo Kiesewetter 75 c. If
VK3 APJ P. Jo Se-btmann 575 11
VK4LT A. Eo Garter 685 tl
"VK5RG R. S. G.urr. 255 II
'VK7SM SoG. Moore 775 11
The Monthly Bulle-tin of the V/ireless Insti-bu-be of Aus-bralia
Se tember 1 6 Tasmanian Division Pa e 3-
TECHNICAL
To return -to the fine ar-bicls submitted, by Leigh Gunther - may I has-tily assure
you tha'-fc'when I refer -to this -topicj 3, 8 " The who done i-t " I am refering -bo the murdered
diode, not; "bo any person or persons concerned v/ith the publica-tion.
HA1F WAVE VS. FULL WA.YE continued
Transien-t suppression. ( no-fce -tha. 't -this does not = elimination ) can be acoomplished
'by pu-fc-fcing a ^).^1 uF / 600V condenser acrcss primary if a full wave circui-fc, and. that plus
a 0. 1 uF condenser acre ss -LT secondary ( or 0. 00-1 uF- across HT, etc ) if half wave.
It is true that half wnve is often, used. cn LT circuits, for which in OA210 or even a BY100
is employed as rec-fcific'r, and safety fact'^r' is more -than adequate-, But these coy.siderations
are important if using, say an OA610 on LT, or the HI diodes cn HT,
1;Vhere: appreciaUe power is to be drav/n, full v/ave gives lower ripple, Be-fcter regulation,
more power ou.t.pu.-t, cheaper -transformer and condensers can be used, output vol-bage is
usually higher, and pe.?.k cu. rrents are lower- for p. given average d. Co out. pu-bo This la-tter
point ensures longer rec'fcifier and fillier condenser life» In. 'bhe case of an SCR, it means
that a 4o7 Amp' SCE. can handle. 4»7 ;»mps if it is fed a. c, or hplf wave d»c., biit a'bou't 6,2
Amps if f&d full wave pulsating d. o. In. -bhe case of ?. bat-tcry charger, a, 'bridge' rec1;ifi.er
configura-tion allows a higher charging rate for a given -bransformer, and the lower peak ^.•::;'
curron-b is much be-t-ter for dibod. es. "nd batterya
A half wave vol-tage doubler has all cf the evils of any half wave sys-fcera, but does have
-fc:iie advantage that any number of stages can. te casoad.ed -bo give any desired mu.l-fciplica-tion
f actor» A full wave vol-bage doubler has high efficienoy, as well as the various advantages
of full wave men-fcionod abcvec. Voltage multipliers have the advantage -fchat. LT -bransformers ar'(
often moreefficient -than HT oneso The vol-tage doiibler ( or B. ny mul-fciplier ), however,
suffers frcm the fact that tho orndensers are su'bjec-fc' -bo high charging carrents, and must;
be in good condi-tion, of high qaali-fcy, p.n.d hp.ving high capaci-ty if anadeciua-be jc'b is -to be
done» This fact -fcends to prevent -the vol-tage multiplier from being the 'best configura-fcion,
but v/i-fchin i-bs limi-fcations i-fc is as good as a full wave bridge. For maximum power from a
given transformer, bridge is simples-b and 'best, even if you. have to neglect the cen-tre -fcap <!
The., Mont h.1 y-Bul-le tin of the Wireless Ins-bitu-be. of AusAralia
-Seis-fcem.'bfl^ •IQ^?. Tasmanian . Division Page- 4
H A. ¥i F E S To
. A CORDI^LL INVIT. 'iTIOF IS EXTEITBED 'SO M.L XYL's YL's and mUa/tONICS TO THE OKCOMICTG
a\I№EST. COTOTCIL ;^TD №I£B£RS OF THE DIVISION W/JIT THIS TO BE AS AFJCH YOUR
OUTING AS THE OM-'s»
EVERYONE IS TO BE CATERED FOR - WE BOKT WMT iIYONl TO FEEL LEFT OUT»
COIViE ALONG AND MAKE THIS T3E BEST OF KLL E.UIFESTS.
••*•• '.
G^iES? COMPETITIONS ^JTD PRIZES » LOLLIES FOR. THE KISS - IT IS A IfflJST -
A Li'iRGE ATTEND^GE WILL BE^LY I';Lkj<E IT. IF TEE OK. IS DIFFICULT = TVCST HIS .IRIA -
.1FTER l^LL YOU LET HIM GO TO THE MEETIEGS SO VVHY SHOULDCTT THE L;J)IES HAVE A CIULN'OE
TO . DBRITO SOME ENJOMENT FROM THEIR OMSs HOEBY.
NOVEIvIBER 27-bh and 28th. THE DATE.
Thanks "bo VKTIIX for his fine list .and suggestions -fco help malce this "the best H^AIFEST.,
Max's l.ist ca-fcers for everything, Toilet Facili-fcies^ Firs-t Md^ Boiling Vfeter§ Cricke-fc Gear
yes even a Rolling Pin ( I have been g-iven a few tips ^.bout throwing these Mum so come along
and see me at the Hamfes-fc - I be-t; I cp. n. fix i-b so yo4 can hit the brats - no fee.)
Next month I hope to pu'blish a full pr'ogramme, any more. su. ggestions will ^e most weloome - •
I would sincerely like to hear from the For-thern. Zone - Let us make it a, -truly Divisional ,.
funoticn — more next monthc
DONT FORGET TO GET YOUR LOG .AV/AY . FOR THE R. D. R3MEIIBEK TIMES IN G>M. T.
• See'you all next mcn-fch
73
Ted Beard VK7EB
for Bulletin. Committeeo