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THE WIRELESS INSTITUTE
OF AUSTRALIA
TASMA^IAN DIVISION
MONTJfflS_ BULLET IN Box 8 51 J. -G, P.. O» MAI 1 62
HOBARE. Price 6d
PRESIDENT. TREASURER SEGEEIAKT
Mr. T. Alien. 3'ir, G. Harrlsson Mr. K. MLllin
VK7AL' • ~ VK7GH VK7KA
Registered at G. P*0; Hobart for tran^niission by post as a periodical,
GENERAL KEEPING.
The nex* Gene ]?al Meeting of -the Division will be held at the Club
Booms, 147 Liverpool St,, Hobarb, on Wednesday, May 2nd. at 2000 hrs»
Visitors •vd. ll be very welcome as usual*
LSGTUBE • •
The lecture -this month will be given ly Prof, G, Ellis on. "Recent work
in: Radio Astromony at the. University of Tasmania",
NORTH WESTERN ZONIi
The nerfc mee'fcing of this Zone uiU be hald at Lakin's Hall, TJlverstone,
on Tuesday, 1st №iy»
NORTHERN ZONE . ., ..
The. date of -the next meeting of the Northern Zone is Friday, IXth May,
Owing -to •fche incidence of Easter holidays this Bulle-fcin is going -to press a. ,.-
week earlier than usual and I have not heard ^diere the meeting is to be held,
GOUITOU, MEETING ' --• •
The next Council Meeting will be held at the residence of oiir
President Mr, Alien on MONDAI, 21s-fc May.
SUBSGKEPTIONS
There are still many subscriptions outstanding. To those paid
- thank you. To •bhose who haven't - we would appreciat-e a remittance.
For the period 24/3/62 to 12/4/62 -fche Treasurer acknowledges receipt
: of subsci-itions from ; VK7GA. VK7TE, VK7SW. 'VK7NG. VK7KH. VKTra:. YKTPA. VK7EF.
VE7CL. VKPW. VK7AG, VK7DR. VK7AX. Y[^7AF« VK7CT'. "VK7LZ. VK7ED. VK7KA. VK7ZAI.
VK7ZBA. VK7ZAO. VI<:7ZAQ. VK7ZAN, VK7ZAH. •VK7ZAX. VK7ZEE. VK7ZAK. Donation VK70M
Messrs. R« G. Shor-fchouse, G. F. Sharp, G* Rsinft, H. A. Hu'tchxnson, G. D. Long,
L. Jacobson, ' ,J. M* Kerr, R. Mbrell, G. G. Waldon, E. Bevis, J* E. Humble,
D. Baigent, H. Harjono, K. L. 'Wheeldon, G. Gannock, G. J, Harper, H. Hiscutt and
W. J. Kickols
CLUB ROOM-FUND.
e ^ckilowledge with thanks donatio&s from Messrs* A»E*Allen VK7PA
and L. Jacobson, 'While'on the subject of -fche Club Room Fund, our thanks also
to Mr, 3S& Alien VK7AL for his'work in coimec'fcion with a control board for the
St. John Anibulance, to Mr, A. Morrisly TC7MI for transpor'biiig same to Launeeston
and -to Mr, iVI, Chaplin VK7GA who has undertaken -bo itistal the board. The funds
should benefit handsomely due -bo the efforts of these members.
NEW №MBERS
The folloying have been elected to membership s Fiill Member. Mr. G. W. frink
VICPGF. Associate! M&ssrs, Harry Harjono, D. G. Baigenfc and G. B. Lut'uiyche,
DISPOSALS.
Crystals listed last month are still available, first come first served.
Price 10s/- each or five for £2-2/-
Page 1
-^ "Th6 Monthly'Hiills-fci^'^f the;№. reless^Iiis^iiut®:-df M^bralia*. ':
May 19^2 \ U ;. ' ' ;- v%smanian^^^on^^^''."'3'a". ''~"';.,' Page., 2
OFFICE BEilBERS FOR T' YE/A 1. ;':- i.6.
At the Council Md^-bJAg. held on Thursday;, .l^h.April, .--bhe following
were elected :
FRESIDEMI: Mr. T« Alien:, VK7AL
VICE PRESIDENTS Ifr, I:,,. Edwards VK7LE -..
№. . C» Harrisson VK7CH
SECRETABZ- Mr, -K. Mllin VK7KA
TKEylSUBER Mr. C. Harrisson VK7GH
MIITOTE SECEET^LRX:' . Mr.: L. Edwards VK7LE
:BUL№riN:' (EDITORS №. K.. Mlllin VK7KA. Mr, 0. Harris son VK70H
(TECHNICAL Mr. A. №rrisly YK7M2"
.
(DISTRIBUTION Mr, T, Alien VK7AL., .Mr. T. Gonnor, VK7GT
BULLETIN
The amount of work'and •fcime . entailed in. ge-fcting the. Bulletin out eaoh
month ts considerable, FirB-bly-fche-AOte^ have.,t:6 be collec-fced, s-fcencilscu-fc,
typing virappers to be organised, duplica-fcihg -66 be arranged and copies collec'bed
when done, pages stapled, circular wapiied and finally posted. Our vor-fcly
Secretary has done a mighty job in •this regard in the past lAien you consider
that about 180 circulars are despatched. In order to ease the wrk it has how
been spread over several members of the Council. In future VK7KA and 'VK7CH wUl
collate the copy and cut the s-bencils, VK7AL and YK7GT wiU be responsible for
coUection, wrapping and posting, T^iile VK7№ idU ensure -that there is a
technical article ready each aionth,
CONSTITUTION
Copies of -bhe DiwLsional Gonstitution have now been duplicated and i-t
is hoped to have them availahLe at the next meeting. Bulk lots will be sent
•fc'o the Nor-bhern and North Wes-bem Zones for 'distilbu-bion and aiy other member
requxring a copy may. obtain a copy from :-bhe Secretary.
V. H. F. NOTES.
The ne3rt meeting of the V. H, F. Group \n. ll be held onMay l6th, This wi.U
probably be the annual meeting - so to prevent you being"dubbed in" for some job,
come along and defend yourself - not th'a-b this will helpJI
Results of Athol Johnson Memorial Con'fcest t
Mr. B. Eyre VK7ZBE
Mr. M. Jenner •VIC7ZAV..'
№, A. Morrisby .VKTMT. '•
Brygn really desfia»»id his wLn as most of his con-bac-fcs wsre mobLle -seems
ss •fchough_the 1'ules are coming goo&» Activi-fcy in'thi.s year's contes-fc lef1« much to
be'desired'- if is expected -bha-fc the stnic-bure of next year*s contest can be.
adjusted to enco-ltrage more activtty, ..
^Nothing DX-wi. se worked on 6 mx recen-fcly. Some stations heard and a fey
commerc-ial harmdiiu. cs. Main reason is probably that no one is iistening.
^Preparations are now in fuTL force for OSCAR il expected anytime* It
seems that the most valuabLe information can be obtauied from doppler shift
measureraon-fcs •• beam direc'fcibns would need to be too precise, Doppler
measurements taken over a number of .^passes enables calculation of"slant height,
velocity and point of do s est approach of •bhe ga-fcellite.
R. Enuuett, VK7ZAO
FLASH BACK . • . '.. -',. ;':1:::" :. :... """•• .
Delving through old rocords I find. that our honoured Patron:'LenGTOoks
VKTBQ was elected'-to-theW. I. A. on 3/9/1925 and to him goesthe-honour-of"
being a member for -the longest period. He was closely followed by Lon. Jen?©n:
VK7LJ and. Bob 0«May VK70M both on 26/11/25 .and, ,Jacilc-,№-Ln&-VK7Aff" on 4/3/l92:6.";:"
Ifcn^-. a dit and a dah hgve those ^old stal, ^^s Isentsc^^ throiigh'the'e^r,
sxface then and it is indeod good t6 knbw'-fchat they gre all s'fcill active, "May
they be spared to pound the brass and/or bash the ndke for mary years -bo come, .:
BULU3TIN ITEMS. " 1:\~''"". -, :". :' . . . ;"-..
We would welcome any items, news, contribu-fcions etc. for the biOletin.
To ensure inclusion in -the next month's issue it must be in -the hands of either
the Secretary or the Treasurer no later than -the third Thursda of each month.
The Monthly Bulletin of -the Wireless Institute of Aus-fcralia
May 1962 Tasmanian Division Page 3
TEGHNI&Uj.
Six Metre E ui ent. So 'buted R< EmmQt-b YK ZAO
The usual reason offered for no-fc building 6 mx gear is -fcha-b tho allocation
is oizly -fcemporary. However, when required, we now know that we m. 11 only be moved
to $2 - 54. mc/s which will'not affect Interstate opera-bion at all, so a receiver
tuning the present band -uill require no modification. Although we do not intend
plugging 6 mx as "official" policy and it is not as ideal for local working as
2 mx, it still has much local and mobile opera-fcion, and a real VHP man should be
capable of operating on both bands. Furthermore standard componen-bs and uiring
procediires can be utilized»
(i) Receiver
The best, approach is a crys-bal con-trolled converter working into a
having preferably a 4 mo/s tuning range in -bhe 7 - 14 rac range. A 6 -^9 rac Command
receiver is ideal. This vri.il allow i-fc to cover the permanen-fc alloca-fcion,
The follow. ng circuit is simpler . -than many commonly used and gives good
results* , ._ . ._ .
(a) To minimise trouble in lining up a 42 Me overtone oscillator is used,
these are only £2 each from a Victorian concern (for info. see a VHP Group
and well worth it- as only one coil is needed,,
Crystal freauency. Mm to -tune from 49*5 nc/s as crystal will osciUate Iq'wer
in frequency than marked. Thus for a 7 mc/s I. F* upwards, use 42. 50 Mc/s crystal,
(b) Val-ve types. Use a 6J6 as mixer and crystal oscilla'fcor as injec-fcxon is
simplified." '"R.,F, stage - 6/iK5. 6A&5. 6AM6.'9003 yithout modifying. 6GB6
Gircui-fc* Layout is fairly non-cntical, but keep all coils at right^angles -
see^ggested layout. Use csraraic cohdensers •fchrougfaout, especially . 001
^passes. I'^ll leads raus-b be short, prune resis-fcor and c<?ndenser pigtails and
mount dieectly on socket.
bJt,
(?^€ s
ft ^
i^-^
L{
•.<
iOO
?•—a)».^
l00(
2-to "X
*00l 33K
LI) 7 tarns No. 18 Xt^l^
L2) 5/8" long. 5/8" diam } iOOK
L3) LI tapped 2 turns ^
from earth. iSQ ^
L4 10 -burns No. 20. /c?o ;£>
1/8" diam. close wund
L5 24 t. 3/8" slug tuned
former (for 7 me I. F.) 01. 02. 03. 3 -30 concen.-bnc trimmers
i. e<a.ct
L-^ ^
Gdk <r c=^> <?^K^ .,
fc
A/^r
L$
^T^t,
Suggested layout on 6"- x 4." chassis.
This article -will be coniinued nescb. mon-fch.
73
G. Harrissori,
Bulletin Gomjiiittee.,
•\