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(o,TR TRV -
REGISTERED AT G.P.0. HOBART Bulletin issued by the Wireless Institute ¢
for transmission by post as Australia, Tasmanian Division, Nerthern Zo:
2 Periodical.
P.0. Box 1010,
J Launceston, 7250. 2
BULLETIN OF NORTHERN ZONE W.I.A. TAS. JUNE,1971.
Page 1.
QO R M may seem a funny name for a bulletin that is to provide
" communication zones. It appears to be fulfilling that function OK -
it dees tell you wvhat Joe Blow is d01ng.
Its title. has upset a few peoPle sinze Q R M stands for man—made
interference. Interfere it will - but why be scared of that. It
.will interfere with the inactivity of some members; with. the"I
couldn't care less" attitude of-so many others and with the ideas
of some people who have their eyes on our bands. You may ask "How
can we interfere with them" ~ the answer is simple - UNITY. :
Amateurs, on the whole, are a nice mob of people. No doubt you have
found outj-a knock on the door of a Ham Shack is all that is necessary
to make 1t ow1ng open to be 1nv1ted in for a very pleasant visit.
And why mot - you have so much in common. You ask for help and you
get it. But why should it be necessary to ask. You knew he was go. i
to erect that antenna. You knew that beginner was having trouble
-with his first tx or rx. Why should he have to ask when it is so
much more satisfying to pay him a visit and make a few casual comments
.-
that will bring the questions flowing. You may even learn something
yourself.
We may at times grumbleabout the benefits or the cost of subs, to
the W.I.A., but remember it is being run by people like you and me
and no matter what club you belong to, there is always some clash of
personality and items on which people disagree.
Remeber - unity is strength and unity comes through the W.I.A.
Have you paid your sub. this year ?
JOHN 7JV
COMING EVENTS
June 1st ® North West Meeting - Lakin's Hall, Ulverstone
June 11th Northern Meeting - Fllms -~ A.E.B. Rooms, 51 York
Street, Launceston
7 June 13th-14th Mt. Gambier Convention.
l July ééth Launceston Council's Visit.
July 1@th Council Meeting Devonport.
August R.D. Contest.
Lo <+te i-e
BULLETIN OF NORTHERN ZONE W.I.A. TAS..... JUNE, 1971, Page 2
The general meeting of the W.I.A. Tasmania Northem Zone, was held at the
Adult Education Rooms in Launceston on the 14th at 8pm, and was well attended by
members and visitors. The minutes for the previous meeting were read and confirmed,
The president congratulated two members Graham VK7GT and Brian VK7BY on arrival of 3
harmonies,
Reports were presented by treasurer, councilor and Australis representative, <«
The treasurer's report showed that the equipment store had really jumped off to a
good start during the month., Councilor John reported on the May Council meeting in
Hobart, and Peter passed on to members the latest information on the Australis Project
(information in later part of this publication).
In General Business the publication Q.R.M. was discussed at some length, The
main points from this being:-
(A) It was a very good thing
(B) Its production should be continued at an economical level
(C) Members may contribute in $%% or items for publication
(D) An endeavour be made to increase number of members in the
Northern Zone
The meeting concluded at 10pm and the next meeting will be on 11th June, 1971.
LINDSAY 7ZLD
YIPPEEEEE HE'S
AFATHER!
CONGRATULATIONS to BRIAN 7ZBY who was presented, by his wife Diane, with their
first baby : a boy. Could be the first of many more,
ALSO to GRAHAM 7ZGT who was presented by his wife - also Diane - with a baby -
also their first - also a boy!
BEVAN 7CX had a close brush with licensing police, Seconds before they burst
in he put an empty glass on the Bar and missed out on being booked,
REG 7KK has real novel ideas about beam instalation. He has 2 and 6 meter
beams on the same mast 20ft. high - one aiming North the other South. Yes, he has a
rotator on it!
WOULD you like to see a beaut little rig. Trevor (BUGS) ¥TB has the FT101
nlus ext. VFD, Also building a X beam for 20m, If you go to see him, a word of warning:
BEWARE OF THE DOG!
NORM 7Z'R left Tassie for Melbourne and took out his old Call 3ZTC (TOP CAT).
But after a month decided that he couldn't do without our company and came back, Now
going to take his old Tassic call 4gain 7 2R,
JOHN 7JV has taken up taming 6/405 on M, S,5,B, John has built the trans-
verter described in A,R. March, 1967. He says it works beaut and is considering
snother one for 140M.
ERIC 7ZEC experimenting with the dnrability of Radio receivers and meter
panels by leaving them out in our Tasmanian weather for 3 weeks or so., Results were
disastrous but it made a good home for the spiders,
HAM school teacher is better known as KILLER among his pupils, The reason
says an ex pupil, is that he is a dead shot with a piece of chalk and a killer with a
blackboard duster, o
FOR SALE: Trio TS510 5 Band Transceiver S.S5.B., AM. and C.W, 160 watts P.E.P,
Including power supnly and microphone. $450.00 0.N.0. Contact NICK LARSEN NL,
43 Upton St, Launceston. 7250.
————
BULLETIN OF FORTHERN ZNE W.I A ...JWNE 1N
NOTES FROM NORTH_WEST ZONE
The Monthly meeting was held on 1st May with a very good attendance, Routine
natters were discussed but the meeting was a comparatively short one, It looks as
though the affairs of the zone are running smoothly, At the conclusion we were treated
to a most interssting lecture on a specialised type of commmication, It-was very
ably given by Mr, Don Cunninghsm of the Department of Agriculture who told us of sorme
amazing ways in which. Honey Bees commmicate, .and their distance- measuring equipment
‘which wéuld be the envy of any ham, Mr, Cunninghemhad a very attentive audience indeed
and we are rost grateful to him for sparing his time,” Many of our chaps. went away
wondering why we need valves and things to do the same jobl
At an odd . moment we asked some of the chaps what they +thought of the new QRM,
Some replies are quoted: 7SF- "Wonderful®, 7KH - "Very good". 7"MZ - "All right~ very
good", 74X - "Pretty good", 7LH - "Jolly good", "Would like a cuestion and answer
section", Associate Tan Ellings - MExtremely 'good%, Graham Rand - "Fantastici"
Couldn't-get any criticism at all!
Believe Tony 7AX has produced a picture on closed circuit T.V,
Les 7LH has lost an clement off the 2 meter antenna - can't hear any difference so
it wasn't working maybe, ;
David 7MS was heard on the Sundey broadcast, It looks as” though the moths.and -
spiders were suddenly ejected from their placid living quarters.
4 couple of the local lads operated on Ian's 7KB antennas one Sunday morning,
Unfortunately the beam rotator had stripped the gears in one of the mighty gales ex-
perienced there lately, The trap vertical was lowered alsc, tumed up ete, and is now
2 going concern, . Possibly Tan's monthly heap of cards will become a bigger heap now,
In the same gale, one of the main nylon stays on "™MX X beam sawed off on the.
chimey, Now it's a Y beam, almost.
Recently Terry 77T phoned 7MX concerning subs, etc. Now here is a good ham going
to waste! At one time he was the rost-enthusiastic operator on the coast, How about
a comeback Terry,
News of John ex VK7JF now 3CDX, -John was host for the night to ZL3DY and XYL en
their way from 7MX to. ZL. No doubt they would find scmething in common as John and
Rex and XYL Margaret all pilot small planes at times,
’mX.
‘Q.R.M, FOR THE SOUTH
Since postal regulations state that 754 of the bulletin must be-posted to members,
it will be quite impossible to keep sending Q.R.}M. to amateurs in the South,
However, if you have enjoyed reading-the two issues that came your-way and you would
like to remain on- the mailing.list it is only nccessary to become a menmber of the
Uortherm Zone, To do this - fill in the form below - of the $1.,00 received from peoplc
cutside the Northemn. Zones-—- 25 cents will be donated to Australis-QOsear B,
S0 kill 2 hirds with one stones.
- (1) 4 donation to Australis - = g
“w_.. .42) A sub, to Q.R.M.
ZONE FEES,
These are now due, Northem Zone W,I.A. members-- remember your zone provides
nany of the facilities available in Hobart - help it by sending your dollar, Complete
the form below if you're wnfinancial,
10
NOI"them ZDne, W-Ivo TaS.,
P.0. Box 1010,
LAUN CESTON,,
T T
I“"AI»'E oooooooooooooo 060 080000600800 .o.c.n-.-.-.t...an-c.oo-oOOQ:CALL~oo----o ........ e e e s
ADDRESS-.voonn.ooucou.onb.c--l ooooooooooooooo 50608 08COE08c s LRI SOPBSEO0SPSOONESANIOBNES
Qo Ro Mn
BULLETIN OF NORTHERN ZONE W.I.A., TAS,..JUNE, 1971 Page 4
During the past two months the zone has purchased from the VK3 division
parts to the value of $400,00, Most of this has already been sold, The following
items are still held in stock,
Contact Kevin 7ZAH at 8 Clarendon Street, Young Town, Phone HOME 460772
WORK 321208
for your re-
quirements,
A3563 0.60¢c ea,
23564 0.60c €
AN 3565 0.,60¢c ea,
VPF 102 FET 0.50¢ ea,
MPF 121 DUAL GATE MOSFET - 0.90¢ ea,
M5145 (TIS88) JFET 0.90¢ ea,
3819 JFET 0.70c¢ ea,
0,7-6PF TRIMMERS 0.25¢c ea,
1,5-9PF P, T.F.E, TRIMMERS 0.25¢ ea,
14 5-12PF " " 0.25¢ ca,
MC 1550 1I.C.,RF,,IF.AMP 1.30¢ ea,
oV ZINER LOW WATTS 0.40¢ ca,
470 PF BUTTON BYPASSES 0.50¢ €aq
RM/08 DIODES 80V P,I.V,1AMP, 0,50¢ €l
NEQOSID FORMERS 0.05¢ €a,
SLUGS F16 + F 0.04c ca,
SINGLE CAMS 0.07¢ ea,
DOUBLE CAMS - 0.08c Ca,e
XTAL SOCKETS.D TYPE FOR
PRINTED CIRCUIT BOARD 0.20c¢ €a,
PACK OF 5 VALVES 1.6AK5 2-6/ub
2-6BA6 1.00c ¢
B/LEE COAX SOCKETS FOR PRINTED
CIRCUIT BOARD 0.20c ca,
RESISTORS 4W INDIVIDUAL VALUES 0.04c €a,
RELAYS /4 CHANGE OVER CONTACTS
12V MINIATURE 2.50¢c Cca,
SOCKETS FOR ABCVE 0.45¢ ea,
W,I,A, CAR TRANSFER 0+15¢ ca,
FIBRE GLASS BLANKS A4'6" LONG
(FOR MINIWHIPS) - 1.50¢c ca,
T,C.A. 167/ CIRCUITS 0.%0c ea,
ATR DUX COILS
HANDBOOKS AWA MR-20B FM CARPHONE
THE M,W, ZONE ALSO HAS A LARGE STOCK ON HAND INCLUDING METERS
CON TACT HAROLD VK7MZ.
Q. R. M,
BULLETIN OF NORTHERN ZONE W,I,A, TAS....JWNE, 1971 PAGE 5
LEST WE FORGET
It is with regret that we rccord the passing of Max Loveless VK7ML, Max is
well known for his efforts during World Wer II,
The article below is from a book called "Signals" and was issued by the National
War Memorial,
"WINNIE THE WAR WINNER",
In the dark days of 1942 when the tide of Japanesc successes engulfed the islands
of the Pacific practically down to the shores of Australia, very fcw people held out
any hope for the troops who formed the garrison of Portuguese Timor, No word from them
had reached the mainland for fifty-nine days and yet during that time the tiny force
of lcss than 400 men had been waging a ceaseless and successful war of their own against
sorc 15,000 crack Japanese troops. They continued to do so for almost twelve months
altogether,
When the Jepanese landed at Dilli on the 19th of February, twenty men of the2/2nd
£, I.F, Independent Company managed to blow up the airstrip and fight their way back into
the hills to join the other units of the garrison in a bitter guerrilla war against the
cnerly despite the fact that contact with the mainlend had been severed,
It was vital to re-establish cormmmnications with Australia and it was for this
purpose that men of the Independent Corpany, the Fortress Signals section on the island
and members of Signals 8 Aust, Div, pocled their resources to build a wireless set
which would be cepable of raising Darwin., They had to start from scratch without spare
parts or new batteries, The sets they had werc too weak; scrounging, the rccovery
of buricd and domaged equipment and raids by fighting scctions into enemy carps for
materials all played part in the construction of the set which finally saw the light
of dey and served the Commandos well and faithfully under thc name of "Winnie the War
Winner",
The first plan was to Puild an oscillator with a stage of amplification to work
on the frequency previously uscd in commmication to Australis, Without a receiver
and with no instruments this was a tall order, but under Capt. George Parker (Signals
8/mst, Div,) four men -~ Cpl. John Sargent and L/Cpl John Donovan (2/1st Fortress
Signals Section) and Sigm Max( "Joe") Lovcless and K, Richards (2/2nd Independent
Conoany) ~ tackled the job, Loveless in civil 1ife had been 'a technician with 7ZL Hobart,
He started by building a tremsmitter, using a crystel which by luck was close to
the r\,qulrod frequency, Power supply became a problem and the couple of available
accumilators were nearly flat, News was received of a cherging plant in a ncarby
village end off went the accumulators under escort to be charged, This procedure
occurred quite o few times until it was managed to make what naturally became known
as a "boong" charger, This instrument of native torture consisted of a system of
wheels, a belt driving a motor-car generator and, as the name implied, was turned by
natives, Their centhusiasm for the job fluctuated and so conseguently did the charging
rate,
A broken~down 109 sct was discovered and the transmitter was stripped for parts
to provide an additional amplifier for the oscillator - more punch, stronger signals,
better chance of being hcard, ‘
Three days after they had commenced to construct the new set, a Dutch sergeant
stunbled into the cemp with what he thought was a transmitter-receiver, It proved
to be nothing more than the usual commercial medium-wave receiving set — and out of
order, too, The scrgecant's effort in carrying this set over forty miles through some
of thc worst country in the world was not in vain for there were many good parts in it
which could be used in the new set,
Loveless planncd to build a transmitter, powerful enough to reach Darwin, from all
the spare parts on hend, He plenncd the circuit and asked all the Cormendos to keep
-their cyes open for ony parts that might be at all useful, Cpl, Donovan went on a
scromging trip to Attamboa, on thc north coast, and retumed with the power pack from
s o Dutch transmitter, two acrial tuning condensers, some sixty fect of acrial wire and
a receiving set,
"WINNIE THE WAR WINNERM,
In the dark days of 1942 when the tide of Japanese successes engulfed the islands
of the Pacific practically down to the shores of fustralia, very fcw people held out
any hope for the troops who formed the garrison of Portuguese Timor, Neo word from then
had rcached the mainland for fifty.nine days and yet during that time the tiny force
of lcss than 400 men had been waging a ceaseless and successful war of their own against
some 15,000 crack Japanese troops, They continued to do so for almost twelvc ronths
altogether, ‘ , '
When the Jepanese landed at Dilli on the 19th of February, twenty men of the2/2nd
4, I.F, Independent Company managed to blow up the alrstrip and fight their way back into
the hills to join the other units of the garrison in a bitter gucrrilla war ageinst the
cnery despite the fact that contact with the mainlend had been severed.
It was vital to re-establish cormunications with Australia and it was for this
purpose that men of the Independent Company, the Fortress Signals section on the island
and members of Signals 8 Aust, Div., pooled their resources to build a wireless set
which would be capable of raising Darwin, They had to start from scratch without spare
parts or new batteries, The sets they had werc too weak; scrounging, the rccovery
of buricd end damaged couipment and raids by fighting scctions into enery carps for
materials all played part in the construction of the set which finally saw the light
of dey and served the Commandos well and faithfully under thc name of "Winnie the War
Winner",
The first plen was to build an oscillator with a stage of amplification to work
on the frequency previously uscd in commumication to Australia, Without a rcceiver
and with no instruments this was a tall order, but under Copt, George Parker (Signals
8iust, Div,) four men - Cpl. John Sargent and L/Cpl. John Donovan (2/1st Fortress
Signals Scction) and Sigm Max( "™Joe") Lovecless and K, Richards (2/2nd Independent
Corpany) - tackled the job, Loveless in civil 1ife had been 2 technician with 7ZL Hobart,
He started by building a trensmitter, using a crystal which byluck was close to
the required frequency, Power supply became a problem and the couple of available
accumlators were nearly flat, News was received of a charging plant in a ncarby
village end off went the accurulators tnder cescort to be charged., This procedure
occurred quite o few times until it was managed to make what naturally became known
as a "boong" charger, This instrument of native torture consisted of a system of
wheels, a belt driving a motor-car generator and, as the name implicd, was turned by
natives, Their enthusiasm for the job fluctuated and so consequently did the charging
rate,
A broken~down 109 set was discovered and the transmitter was stripped for parts
to provide an additional amplifier for the oscillator - morc punch, stronger signeals,
better chance of being heard, ' )
Three deys after they had commenced to construct the new set, a Dutch sergcant
stumbled into the cemp with what he thought was a transmitter-receiver, It proved
to be nothing more than the usual commcrcial medium.wave receiving set — and out of
order, too, The scrgeant's effort in carrying this sct over forty miles through some
of thc worst country in the world was not in vain for there were many good parts in it
which could be used in the new set,
Loveless planncd to build a transmitter, powerful enough to reach Darwin, from all
the spare parts on hand, He planned the circuit and asked all the Cormendos to keep
-their eyes open for any parts that might be at all useful., Cpl. Donoven went on a
scrounging trip to Attamboa, on the north coast, and retumed with the power pack from
o Dutch transmitter, twe acrial tuning condensers, some sixty fect of acrial wire and
a rcceiving set,
The task of building "Winnic™ went ahcad without delay. Coils were wound on
bamboc formers, accumulators were rccharged, points were soldered and valve sockcts
werc nmade, Just about everything had to bc guess work in the absence of precision
tools and instruments, even to the perusal of a Portuguese radio manual to determine
the color code of rcsistances and condensers, A battery charger was recovered fron
the cneny when fourteen Cormandos went through the Jepanesc lines to the old Australien
H.G. at Villa Maria, Only a hundrcd yards from the Japancsc they dug up a cherger which
had bcen buried there when the H.Q, had been forced tc mowe,
The sct was rcady to go on the air by the 13th of April when the cperafor
raisc Australia with "C.Cs," end "Xs" but no recply was hcard, Tuming the &
recciver, the sounds of music floated into thc small shack, Some ftroubsdors
ing the listening public with a scng about "The Last of thc Hill Billies™,
mitter was revised and on the 18th of April another atterpt was made fo contzet The
mainlend, No reply was rcceived but the diseppointment of thc men woulé hawe beem
allaycd had they been awarc that their signals had been picked up =nd passed e %o
Daerwin, All Australian transmitting stations werc wamed to keep off the zir =mdé 1isten
for Tiror on the following night,
Somc days prior to the 19th of April the H,Q. of "Sparrowforce™ (as the Cor=xmdos
werc known) had given thc operators a couple of -cneoded rcssages "just in case®, On
that fateful night, "Joe" Loveless tuncd up the rig and cverybody stood by listaming
tc the chosen group, With suppressed cxciterment the 'brass was pounded®™ and the
highest priority put into the call, The cperator was preparcd to do this for a2 cowple
of hours but a hefty answering signal camc back in reply. He was so ncrvous that he
could not tap out the answer fast enough, Although hc did not know it, 211 fustrali=m
staticns on the group were ordercd to stand by and after somc hours the messages were
passcd, A tin of Australian tebacco which had becen kept for such an occasicn was cpaned
in cclcbration end a toast in coffec was drunk to "Winnich,
On the following night contact was cstablished agoin but this timc Darwin was
suspicious and demanded proof of the guerrillas! identity, Qucstions and enswers ‘
were flashed across the Tiror Sca: "Do you know Jack Sargent?"WYes, he is here,®
"What renk? Answer immcdiately". ‘'Corporal," "Bring him to thc tronsmittert, "ihat
“is your wifc's namc, Jack? " "oan," Mhat is your strcet And house number?®
" The corrcet answers were flashed back and the mainland accepted the fact that the
Australiams
in Timor werce still alive and fighting, Strengthcncd by the assurance
that their homeland was meking cvery cffort to hclp them, the men in Timor fought on.
- They 1ived like natives, scrounged their food in the villages, out—fought the Japancsc ‘
and ‘mocked the surrender notes with which the cnemy rcgularly assailed them, The }
Jopencsc commander paid them a hard-won tribute when he saids "ou, alonc, do not B |
surrcnder to us," /
On thce 26th of Apr:l an Allled planc camc over so;rchn.ng for the party but missed
the smoke beacons, It returned just on dusk the following night and dropped parachutecs
with prccious food and stores, Bush wircless tcok up the glad ncws and men who had
~becan ‘going barefeoted to save their boots for more active work. were issucd .with new
pairs, It was thon that a1l kncw that "Winnic" had made good,
The mainland wasted no time in asking for bombing targets which were promptly
and happily supplicd, Thce men then enjoyced the sight of Allicd bombers passing over-
head on their way to give the Japanesc a taste of their own medicine, A rcmarkablc
instance of co—ordination occurrcd when interference halted a message regarding bombing
targets that was bcing passed onc night to Darwin, When conditions improved at 7 o'clock
the next rorning, the message was ccrmpleted. As the operator was rccelving an ac-
Imeowledgrnent from Darwin, our borbers were overhecad on their way to the target,On
cnothcr oceasion, an cnemy ccnvoyof three ships was sightcd and a message promplty
despateched to the mainland. The R.AVALF, sank all threé¢ and rclieved an ugly situation,
"Sparrowforec® toock fresh hcart from such things, The ren rcalised that they
were no longer a lpst unit but another 1link in the chain that was then being welded
for the final overthrow of the cncry.
"Winnic the War Winncr® did noblc work end as a fitting climex to a uscful carccr
guided the rescuc party that cventually took the gucrrillas home from Tirnor,
This weird but wonderful sct now rcsides in the Australian War Mcerorial where it
occupics an honored place as a rclic of the Ingenuity of signelmn in the face of
odds and difficultics. T ) o : .
Qe Re M,
BULLETIN OF NORTHERN ZONE W.I.A. TAS....JUNE, 1971 Page 7
AMSAT NEWS,
Their latest newsletter tells that there could be three repeaters lawunched
together, NASA Headquarters have gpproved the launch of AMSAT -~ OSCARB as a
secondary (piggyback) payload., A mission with which OSCARB cean ride has not yet been
identified but it is hoped this will be done shortly so that a tentative launch date
can be announced,
The equipment to be included in the A-0-B satellite is (subject to cheange):
For the Australis Repeater:
Uplink: 145,800, 145,850, 145,900 and 145,950 MHz
Downlink: 432,200, 432.250, 432,300 and 432,350 MHz
4 TM paired chennels
For the DJAZC/DI5KQ Repeater:
Uplink: 432,150 MHz Center Frequency
Downlink: 145.950 MHz Center Frequency
50 kHz Bandwidth, Linear Repeater
For the 2/10 Repeater:
Uplink: 145,950 MHz Center Frequency
Downlink: 29.500 'MHz Center Frequency
100 kHz Bandwidth (miriimum) Linear Repeater
Details of the Australis Repeater have been fairly well covered but the other
two devices are not so well known,
AMSAT 2/10 REPEATER
Australis - Oscar 5, with its ten meter beacon provided the stimulus for this unit,
Listed below are the basic characteristics of the 2/10 repeater “breadboerded"
version.
Input Frequencyv: centered at 145,95 MHz.
Qutput Freguency: centered at 29,5 MHz (note - this represents a change fromthe
previously announced frequency of 20,6 MHz which turms out to
be the natiocnal ten meter M frequency in the USA,)
Beacon Freguency: 29.45 MHz (Same as Australis -Cscar 5), '
Repeater Bandwidth: measures 120 kHz at 3 dB-down points, 150 kHz at 6 dB down,
and 240 kHz at 10 dB down, This means that stations capable of operating with
higher power than that normally required to operate through the repeater can
operate further from the repeater center frequency thereby avoiding QRM from
other stations using the repeater, In other words, the usablé bandwidth for
high power stations is approximately 240 kHz,
Repeater Qutput Power: presently measures approximately 1.3 watts; final goal
is two watts PEP,
Input Sensitivity: approximately 100 dBm ( 2 microvolts/meter) for full repeater
output. ;
Ground' Station Power Required to operate through the Repeater: 80 watts of effective
radiated power develops full output from the repcater, essuming a maximum distance
to the satellite of 2000 miles, /n eight watt transmitter and 10dB gain antenna
should be sufficient, or a €0 watt transmitter and an omidirectional antenna,
Mntenna Gain Required for Reception:O to 8 dB, A ten meter dipole or beam should
give good results at a maximum distance to the satellite of 2000 miles,
/95*75‘ ‘ MIXER Mixe BFAT) 35_Balarces! Moxed
rMH, PN'M 79
Qv fov g
Folt outpe?
The equipment to be included in the A-0-B satellite is (subject to change):
For the Australis Repeater:
Uplink: 145,800, 145.850, 145.900 and 145,950 MHz
Downlink: 432,200, 432.250, 432,300 and 432.350 MHz
4 M paired chennels
For the DJ47ZC/DIS5KQ Repeater:
Uplink: 432,150 MHz Center Frequency
Downlink: 145.950 MHz Center Frequency
50 kHz Bandwidth, Linear Repeater
For the 2/10 Repeater:
Unlink: 145,950 MHz Center Frequency
Downlink: 29.500 'MHz Center Frequency
100 kHz Bandwidth (minimum) Linear Repeater
Details of the Australis Repeater have been fairly well covered but the other
two devices are not so well known,
AMSAT 2/10 REPEATER
Australis - Oscar 5, with its ten meter beacon provided the stimulus for this unit,
Listed below are the basic characteristics of the 2/10 repeater "breadboarded"
version,
Input Frequency: centered at 145,95 MHz,
Qutput Freguency: centered at 29,5 MHz (note - this represents a change fromthe
previously announced frequency of 29,6 MHz which tums out to
be the national ten meter FM frequency in the USA.)
Beacon Freguency: 29.45 MHz (Same as Australis -Oscar 5),
Repeater Bandwidth: measures 120 kHz at 3 dB-down points, 150 kHz at 6 dB down,
end 240 kHz at 10 4B down, This means that stations capable of operating with
higher power than that normslly required to operate through the repeater can
operate further from the repeater center frequency thereby avoiding QRM from
other stations using the repeater, In other words, the usable bandwidth for
high power stations is approximately 240 kHz,
Repeater Qutput Power: presently measures approximately 1.3 watts; final goel
is two watts PEP,
Input Sensitivity: approximately 100 dBm ( 2 microvolts/meter) for full repeater
output,
Ground Station Power Required to operate through the Repeater: 80 watts of effective
radiated power develops full output from the repeater, essuming a maximum distance
to the satellite of 2000 miles, /Mn eight watt transmitter and 10dB gain antenna
should be sufficient, or a €0 watt transmitter and an omidirectional antenna,
Mntenna Gain Required for Reception: O to 8 dB, A ten meter dipole or beam should
give good results at a maximum distance to the satellite of 2000 miles,
/95%35 ' MIXER MixER
M"/pb 2"’/?3;79
v F‘-’ - A" Sl
f:u// ovtpoe 71 —
o
295‘ M//J.
Q"fm’se Mme/’?
' 2N 337 2/v7/3‘ N
Fina/
Amp Do,
Q. R. M,
BULLETIN OF NORTHERN ZONE W.I,A, TAS...JWNE, 1971 Pagséd
THE DJ4ZC TRANSLATER
The figure gives a system diagram of the translater and demonstrates a relatively
new technique of elimination and restoration of the envelope of a signal to obtain
Ligh modulation efficiency for the limited power system on the satellite (SOLAR CELLS). *
In a conventional converter the 432 MHz signal from the ground is heterodyned twice*
to a 10,7 MHz.IF, A 50 khz crystal type band-pass filter made especially for,the
purpose sets the bandwidth of the repecater and limits the noise through ift,
After amplification end insertion of a2 beacon signal for telemetry and tracking
purposes a twofold detection is used to obtain:s
(1) Regular AM-diode detector to yeild a signal envelope;
(2) A phase angle signal corponent similar to derodulation recovered
from a high gain amplifier-limiter,
Other practical refinements to assure low power drain and linear operation were
used by DJ4ZC.
Specifications of the "TRANSLATER.H" as they are now follow:
Center Frequency inN.....o.... sesosseassh32.15 KHz
Center Fregquency oUb.eeeoececceaoecocsss 145,95 MHz
Passband.eeeosceccoccocosscssssacasasssO KHz
Max, Output Power...eee.vococsones ceeo 10 W PEP
Low Power Mode outpul power.e..icesess. 2.5W PEP
Beacon Frequency...co. . ooocescsccsocees 145.975MHz
Input Sinsitivity for full output..... 1.5 uV
(-103dbm)
CW, MM, ™, or SSB can all be used,
For an amateur to communicate through the orbiting "TRANSLATER-H" a 10dB antenna
godin with 20W transmitter power at 432 MHz should be available according to our
ccleulations, For receiving a 10 dB gain antenna connected to any of the commonly
rvailable 2 meter converter or receiver arrangements suffice,
To judge from comments of all those involved during that December test period ’
cuite an education resulted end it should benefit in better ways and means for
constructing satellite transponders, Meny insights were gained, such ass durimg the
transition to vacuum corona occurs if the transmitter is on and can damage components
if they are not located and chosen properly.
Since the coming Oscar hopefully will stay up for more than a year, all active
VHF amateurs should be gble to makc transcontinental contacts with equipment they
mostly already have,
MIXER Mixe R
—— - = —"‘T"
lfimA ’HMfi 'sz IF DET E%/V
|X3 _j"2 ol
-z —A{;‘l !
AGEC BEfic ’wwme
/o FPrRASE __in/Fo oLy ouT
ZERO CROSS /NG ,4-5.9 M//1
|AM% 1/»1/:1’°°""[p S— Fone 2-5~/0w
3927
135MH, h
145} FEK
osc
SAM P/,g
HOLD DIF/’[(’F/}?IAK’
B/A CompPrtaie, ALEC .
FBx = fifi// :
. S 3. SRR g § as I
VT T AR
R eRCan R Tl e R T Ro A i - dl *o 2 RetN S SL
purpose sets the bandw:Ldth of the repeater und limits the noise through it,
After amplification and insertion of a beacon signal for telemetry and tracking
purpcses a twofold detection is used 1o obtain:
(1) Regular AM-diode detector to yeild a signal envelope;
(2) A phase angle signal corponent similar to demodulation recovered
from a high gain amplifier-limiter,
Other practical refinements to assure low power drain and linear operation were
used by DJ4ZC,
Specifications of the "IRAVSLATER.H" as they are now follow:
Center Frequency in,........ cossscssesesh32.15 KHz
Center Freguency olb.eeeeececcoooecese145.95 MHz
Passband.,...., ecceccccscsscacsasaassasdl KHz
Max, Oubpult Power....oeccocecocococess 10 W PEP
Low Power Mode output power.... cesesss R+5W PEP
Beacon FreqUenCy..ooeo- ocoscscsscssese 145.975MHz
Input Sinsitivity for full output..... 1.5 uV
(~103dbm)
CW, AM, M, or SSB can all be used,
For on amateur to communicate through the orbiting "TRANSLATER-H" a 10dB antenna
coin with 20W transmitter power at 432 MHz should be available according to our
elJlculations, For receiving a 10 dB gain antenna connected to any of the commonly
nvailable 2 meter converter or receiver arrongements suffice,
To judge from comments of all those involved during that December test period
cuite an education resulted and it should benefit in better ways and means for
constructing satellite transponders, Meny insights were gained, such ass durimg the
transition to vacuum corona occurs if the transmitter is on and can damage components
if they are not located and chosen properly,
Since the coming Oscar hopefully will stay up for more than a year, all active
VHF amateurs should be able to make transcontinental contacts with equipment they
mostly already have,
il MIXER Mixe R
932 y
E ?l
1 ! /0: 7’%
l [zu/[,__,_li AN
MH, /)Mf—? AMP IF (5 Env
l , ‘ !(3
2| BE” u/wr:,q
GC
IX3 ]( oSc 7/ C
PHASE n/Fo oLy ouT
145.9 MH,
‘AMV‘lnmrl
JoosH|, 2-5~/0ow
135MH,
%fe 457 FE&
A 31 Ose
Dse
Fuy
v/
SAMzg
Horp DIFFeRENT
4L
B /A CompPrfiiok AL
FBk fij___cfl'fl :‘;{ = 3 ' - 2
PUIS
'700 xfi.{\fl
FLip
Oac Flo s 2 ; g pop o
10 e
Ql R' Id‘
BULLETIN OF NORTHERN ZONE W,I.A, TAS,..JUNE, 1971 Pag67
oM SUPEREGEN
Northern nembers - let's 21l build this unit and have some transmitter hunts in
the next few ronths,
6.3 PF
L1 13T.3"D T.C.W,
L2 3LT.:'D T.C.W.
C1 2~10PF CERAMIC SCREW TYPE
TRIMI'ER
RFC 24T,3"D 26 SWG EN,
T1 INTERSTAGE TRANS,
EX TRANSISTOR RADIO
TRI 0C170 ETC.
. (BF115 REV, POL.)
Al (23564 )
The original receiver was built in a mustard tin with the screw type trimmer & pot,
together with a phono type female socket mounted on the 1id, A garmma matched dipolc
scldered to a plug fitted directly on the 1id, The amp, used was a single 0C71 driving
2000crsheadphones, Other suitable high frecuency transistors should work equally as
wcll, Sensitivity was such that 2-3 uv was a readablec signal,
SIQNAL TNJECTOR fi Y
20
The injector uscs components
available on sore of the com-
puter boards, The astable
mlti circuit provides clcan
square waves with risetimes
034 fast cnough to produce a
herringbone pattern on a T.V.
receiver tuned to Channel 3.
The original was built in an aluminium tube with an insulated probe on one end and a
~ush button mechanism on the rear to contact the 1.3v mercury cell, With a supply of
1,3v the current drain is approx. 4MA and a voltage output at least 1 volt,
BOB 7ZRF
MINIWHIP
A note from Doug, 7AB, tells of his cxperience with these antennae., He uses it
on his Swen and has it mounted on a ski rack across the top of the case, On 80 metres
he usces a base load into which is screwed the A0 metre, whip,
Results on all bands arc "fantastic" according te Doug - tec prove it hc worlks ZL
robilc on €0, G on 40 metre phone and the best on 20 being mobile to mobile with G3JAF!
He alsc mentions a QST article which is apparently, the original source of information,
Thanks Doug, for this information and your interest,