Morsum Magnificat-MM41
Morsum Magnificat-MM41
Morsum Magnificat-MM41
a1 teat
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Contents
S YOU WILL KNOW from this page in the last issue 2 News
of MM, I do not have a great regard for the methods
6 Readers ABS
of modemday singleissue pressure groups, as
epitomised by the New Zealand antiMorse organi- 8 NZ No-code Controversy
sation ORACLE. My opinion of that particular group was not Continues
improved when I read ORACLEs response to Gary Bolds 12 Learning the Other Code
views as published in MM4O (see page 8 ofthis issue).
In this, they try to hide behind the Privacy Act in New 19 A New Look at Morse
Zealand as an excuse for not revealing just how insignicant in Communication
numerical terms their support must obviously be. I nd the
sheer arrogance of their statement .., ORACLE wishes to 22 MARS to
have the image of placing quality policy discussion before Discontinue CW
amateurs and politicians rather than debating support bases 23 Bookshelf
totally breathtaking! Those behind ORACLE should perhaps
be reminded that they live in a democracy, where (in theory at 24 Showcase
least) it is still the views of the majority which count. 26 The Morseman of
A couple of days ago, I came across a review in the
Godzone
UK newspaper Daily Mail, talking in that case about a
documentary TV programme of the previous evening, which 34 Info Please!
expresses far better than I can the true nature of groups such 36 Your Letters
as ORACLE:
These groups are characterised by their success
44 MM Back Issues
in bullying elected politicians, their carelessness 45 Index to Issues 35-40
with statistics, their disregard for any views
contrary to their own, and their childlike
determination to get their own way.
In any case, it could be that this movement to brand doerts
competence in Morse an irrelevancy is, to say the least,
premature. We understand that Morse is still being taught in
the British Army, while in the RAF, an indepth review of 44 FISTS CW Club
the benets of retaining a Morse capability is under way. And,
7 The QRP Component Co.
of course, for visual (ashing light) communications, Morse
is still in use between warships of the NATO navies. 44 G-QRP Club
In a late news feature on page 22 of this issue, there is 33 G4ZPY Paddle Keys
an announcement that the US MARS organisation is to discon
tinue Morse from October next year. I dont doubt that the International
military can afford some very sophisticated Morse-decoding
programs, but can they really read the sort of mangled Morse
that a skilled human can cope with, as Assistant Secretary of
Defense Emmett Paige claims?
ti
MOVING HOME? Please let us know promptly ifyou change your address, including details of
the old address so that we can be sure we are updating the right subscription record. Also, tell us if
you have been one ofthose aected by the programme ofchanging postal and zip codes which seems to
be going on in various parts of the world. Remember, too, to let your bank and credit card companies
know of the change, as they may refuse to authorise payments of subscription renewals, etc., if the
address and/or post code information on their les is out of date.
Britain.
nication, but rather as aids to efcient An account of the 1894 demonstra
operating. tion was given in an article The First
The actual modes used on the air are Radio-telegraph Transmission, by
listed as: FM 79%; SSE 79%; CW 54%; Rowland Pocock in MM14, p. 1.
Packet 40%.
If over 50% of radio amateurs still Morse Tests on Demand
use Morse on the air, it follows that Amateur Morse tests are available on
1
CW is not yet ready to be declared a demand when the Radio Society of Great
minority mode! Britains HQ is open on a Saturday. At
No booking is necessary, but candi- UN. He hopes to use the call on both
dates must take with them the test fee of CW and SSB.
18.00 for the 12 wpm test, or 13.00 Last year he made 2000 contacts on
for the 5 wpm test, also two passport- CW with the special call 9I3OZIN, cele-
type photos. brating 30 years of Zambian independ-
The Milton Keynes & District ence. If any MM readers contact 9JSOUN
Amateur Radio Society, which has two on the key, please mention the magazine
RSGB Morse examiners amongst its if the opportunity arises.
members, also runs tests on demand
sessions once every two months. Morsecodians at Alice 1995
MM would be interested to know if As mentioned on the back cover of
other radio clubs offer the same facility? MM40, the Morsecodians Fraternity
Please send details to the MM editorial operated their annual telegraph land
ofce. line from the National Science &
Technology Centre, Canberra, to the
Grants for Morse 2000 Outreach historic Overland Telegraph Station at
The Morse 2000 Outreach reported in Alice Springs for nine days in April.
MM40, p.5, has received a $7000 grant The line was also linked to the Killer
from the American Radio Relay League Whale Museum at Eden, New South
Foundation, and a $1000 grant from .
Wales, where whaling was the main
the Dean of Human Sciences and industry at the turn of the century. Eden
Services at the University of Wisconsin is near the NSW/Victoria border, on
Eau Claire. the shores of Twofold Bay, one of the
These grants, plus additional funds deepest harbours in the world. The Eden
hoped to be raised, will help cover costs circuit commemorated the 125th anni-
of communication, mailings, and devel versary of the Eden to Gabo Island Light-
opment of the outreach and the 1997 house telegraph line, also the arrival in
world conference, which will be con- Twofold Bay of the replica sailing ship
cerned with Morse code applications in the Endeavour. The Endeavour was the
rehabilitation. ship in which Captain Cook reached
Requests to be placed on the Morse Australia in 1770.
2000 mailing list should be made to Dr Each year the trafc on the Canberra
Thomas W. King WF9I, Department of Alice Springs circuit increases so
Notice of some of the amateur radio- Radio & Computer Rally will be
related events being held in the UK held at the Aberconwy Conference
over the next few months. Although Centre, Llandudno
keys (other than the various WT * On
Sunday, December 3, the
8AMP and NATO models) and oth National Vintage Communications
er telegraph bits and pieces are be- Fair Christmas Special will be
coming scarcer all the time, theres staged at the National Exhibition
always a chance you may make a Centre, Bimiingham. In response to
worthwhile nd, but be there early! . demand from traders and visitors
* On
Sunday, September 3 the Tel- alike, organiser Jonathan Hill has
ford Amateur Radio Rally will be agreed to stage this extra show for
held at the Exhibition Centre, Tel- the rst time in 1995. As well as the
ford, Shropshire, doors open at usual range of vintage radio, TV, tel-
10.30am. ephones, gramophones and classic
Also on September 3, the Bris- audio and hi, this Christmas show
tol Radio Rally will take place in will be extended to include scientic
the Brunel Centre, Temple Meads instruments, sewing machines, type-
Station, Bristol, from 10.30am to writers and other electrical and me
4pm. chanical antiques and collectables.
* The Leicester Amateur Radio At past shows, there have been a
Exhibition will take place at the number of telegraphyrelated items
Granby Halls, Leicester, on Friday on sale.
and Saturday, October 20/21. The MM/RB team will be in at
* On Saturday and Sunday, tendance at each of the above shows
November 4/5, the North Wales marked with an *.
Keyers
Curtis 8044ABM chip 19.95
Oak Hills Curtis keyer 33.95
kit
assembled pcb 44.95
R A Kent Electronic keyer kit 45.00
ready to use 59.50
Morse Tutors
GSTUX Omega multimode 44.95
R A Kent 49.95
ES G3TUX
The QRP Component Company
VISA
matters that affect them world-wide. news about the no-code controversy or
To do this, we rely on you to tell us what any other Morse matter. Our addresses
is happening in your country. Please are inside the front cover of every issue
write to Geoff or me with your Morse of MM.
MM41 ugust 1995 11
N THIS ARTICLE, we shall con-
sider how to go about learning the Learning the Other
other code. Since most of us know
the International (formerly called Con-
Code
tinental) code, how do we go about by Wm. G. Pierpont NOHFF
learning the old (American) Morse
landline code?
Do not use the following compara-
tive lists in any way to learn the Ameri-
can code. Their purpose is solely to show
the differences between the two codes,
and particularly the effects on the struc-
ture of certain characters due to the
Morse internal spaces and the special
lengthened dahs. They affect rhythms.
First, the old Morse differs from In-
ternational in four aspects: 0 (zero) = a still longer dah
1. The following characters are THE (see below).
SAME in both codes: A B D E G H I K The following numbers are different
M N S T U V W 4 (2/3 of alphabet in old Morse from any International
letters) English character sound: 2 3 6.
2. A number of International characters This does not include other punctua
represent DIFFERENT letters or num- tion, which differs and in old Morse
bers or signs in old Morse: landline circuits was used extensively.
MORSE: FJQPX15789 . ? It must be heard to learn it.
INTNL: RCFSLPOZ6X?/
3. Certain old Morse letters contain IN Timing
TERNAL SPACES which make them There seem to have been no stand-
subject to possible misinterpretation as ard timing relationships in American
two letters, i.e.: Morse as compared with International
C O R Y Z Morse. That is, the duration of a normal
might appear to be: .
dah is stated variously as being two times
IE EE EI II SE or three times the duration of a dit. (My
4. Certain letters in old Morse are DIF- own impression is that it tended to be
FERENT from any International char- somewhat shorter than the correspond
acter for English: ing dah in International code. This might
L = a longer dah I
have been done to save time and yet to
OOONOOIhUNl
II
xg<camzovozgrxu-Iommunw>
Interrogation (1) -
Paragraph
l
16 MM41 ugust 1995
available from: Cecil Langdoc, 201 operation over wires, where static and
Homan Ave., Elkhart, IN 46516, USA. other interference are absent or mini-
They make for great listening.) mal. Although the International form
A Railroad telegraphers story: a of the code was developed and adopted
beginning operator was sending as fast in Europe only 5 years later, in America
as he could with a bug when the other the earlier code was at rst used for
operator cut in with what he copied as wireless.
REND STOW IMA GIRT. He asked Two factors probably acted to effect
for a repeat and got the same copy. He the change-over to International: the
turned to his supervisor and asked: predominantly ditty character of Amer
Whats wrong with that operator? The ican Morse sounded more like static than
reply: Nothing, shesjust saying Send the International form, and the world
slow Im a girl. Youve gotta learn the wide nature of shipboard wireless oper-
difference between R and S and T and ation urged a common code. This would
L. Didnt they teach you anything in have become more demanding as
that school?
ously cited 10% faster. Therefore, when (or exaggerate) their time intervals (sig-
we read of the speeds achieved under nal on and spaces) to aid in copying. If
American Morse operations we need to they do so, then the time gain is less.
recognise that the sending operator is
having an easier time than the corres- Some Practice Materials for Learning
ponding International operator, but the Words which contain only letters
receiving operator is under the same bur- common to both codes: (a e i u b d g h k
den, and needs a more acute ability to m n s t v w) the and end man men view
discriminate small differences than his stew must mist missed kid king thing
corresponding International operator. dig dumb sing sting stub hide side vast
In addition, when both have com waste waist medium wide stab tug aim
pleted sending the message, the Morse bug tame name magnet tube gust huge
operator will have used only about 91% India ink sink had mad made human
as many keystrokes and about 85% of
1
fax
e -
Morse signals.
Some decades ago, the so-called
400 000 theory was popular in the
audio eld. This theory says that the
frequency range of audio reproduction
is best balanced when the product of the
high and low end frequencies equates
to 400 000 (e.g., 50Hz8kHz or 25Hz
16kHz).
Although there are some objections
to this theory, suppose we adopt it and
Photo 2. La Torre di Pisa. narrow the bandwidth to 1/3 octave, i.e.,
Final 4 inclined-key a range between 560Hz and 710Hz, with
a centre frequency of 632Hz,
which is the square root of
400 000. This would be an
appropriate frequency range
for receiving CW continu-
ously for a prolonged peri-
od. Figure 2 shows an
L. ['4
c. c3 c4 (6
0: 63 2H2
Zin =Zout=5009
L1=L3=15mH
L2=6 OmH
Cx=C6=4 uF
C2=Cs=0.3uF
C3=C4=1.8uF
Fig. 2. Audio band-pass filter with
In.
3 ,
m.
3
um
!9
um sun
9
sun
3. .r
sun um
1'
nm
3
no.
,2
sun
9
5
IJ passband between 560Hz and
710Hz, with a centre frequency
of 632Hz
mu} NJ 96.!
13"
example of an audio bandpass lter depends on the speed of the Morse sig-
which has this passband. nal (see Fig. 3). We can estimate a
In my opinion, however, the opti- reasonable formula for this but it can
mum frequency is not constant, but only be used to determine the modulat
l2 ing frequency of an A2 transmission.
My suggestion is a formula with the
IOO
square root of a Baud rate dened as the
- 90
\lm CC)
inverse of a dot length multiplied by a
coefcient of 200. the coefcient can
(Letters/min
vary with individuals: the dependency
of the coefcient is found to be surpris-
ingly small.
mm
C
f = 200 \/B
.2. 0
B = k x P/60
SPEED
where
f = frequency (Hz)
LA)
0 B = Baud rate
600 700 800 P = numbers of letters per minute
FREQUENCY (HZ)
k = 8.0 for English code
Fig. 3. Comparison of English and 13.2 for Japanese code
Japanese code relating to
audio frequency v. speed continued on page 48
MM41 ugust 1995
21
he Military Afliate Radio System
(MARS) operates numerous commu
MARS to
nications networks on US military
frequencies and thousands of radio Discontinue CW
amateurs participate in it.
Its main mission is to provide a backup
to military communications and to support
worldwide civil emergency and disaster
communications. It also handles health,
morale and welfare oriented trafc.
In July, the following message was
transmitted from Air Force MARS at Scott As an Assistant Secretary of Defense
Air Force Base in Illinois. This was only
Hay
Photo:
WW7P.
Elwood
John
Collection:
l_
Manhattan Electrical Specialty Co. (MES). Contacts replaced with coins (i. e., dimes,
hence dime key). A telegraph key modified for use as a spark key by hams in the
early days of wireless
.
10
Photo/Collec
Flameproof J-7A key, dated 1921, Order 141092. Made by LS. Brach Mfg. 00.,
Newark, NJ. Said to be as used on USN Blimps
VE3FHX
WI'I/er
Murray
Photo/Collection:
Davies
v1"
Wyn
_
swam Manirorae
Photo/Collection:
member of the CFO, which started out Sinister Symbols from the Past
as a loosely-knit bunch of US keyboard .
(From the USA 3)
enthusiasts.The entry requirements were, About a year ago, somebody (my les
roughly, a deep love of CW, and a habit are 8500 miles away) asked me about
3
Audio or IF Filters?
get our junk out of cold storage. Keep it (From the USA 4)
in the editorial sanctum where you can I was asked recently why is it
lay your hands on it quickly in an emer~ considered better to have a built-in, IF
gency. We will soon be allowed to CW lter, rather than simply tacking an
transmit, and then you will need it. audio lter between the receiver and
Accompanying this was a weird, mis- the phones? Surely they just achieve
shapen, wooden, wire-bound two the same result?
pronged tuning fork-like object. The Well, they may not do QUITE the
Wouff Hong. Theres one displayed in same thing IN PRACTICE. The SWAN
ARRL Headquarters to this day. rig Ive borrowed from Jesse, W8MCP,
After his death, it was revealed that has no built-in lter, so Ive also bor
T.O.M. had been Hiram Percy Maxim, rowed an excellent MFJ audio lter
the rst President of the ARRL. It is said from him. The problem arises when
that he took the secret of the origin of theres a very strong signal close by the
the rst Wouff Hong to his grave. But I weak one youre trying to copy. Even
have also heard it rumoured darkly that though the beat-note from the strong
some still alive know what it really was. signal cant be heard in the ltered au-
One day, I will make a pilgrimage to dio, it DID come through to the product
Connecticut and View it for myself. detector, and may cause blocking a
A photograph of a prominent ZL decrease in sensitivity whenever its
Ham reverently handling a Wouff Hong present.
actually appeared some time ago in It helps (as always when receiving
Break-In. Again, my back copies are far CW) to turn the AGC OFF, and back off
away Ill tell you which one when I the RF gain control until the desired sig-
get back to Godzone country. nal is just causing the S-meter to rise
An even more sinister disciplinary slightly. Even this may not get rid of
device was the Rettysnitch. David passed rather disconcerting staccato level vari-
me no information on it save a photo, ations on it.
bearing the unnerving legend A formi An IF lter, on the other hand, blocks
dable substitute when the Wouff Hong out the strong adjacent signal BEFORE
was engaged elsewhere. The Rettysnitch it gets to the detector, and usually
gets
MM41 ugust 1995
29
around this problem. I say usually, be- Ham band. Choose any character, and
cause many CW lters are not narrow get the sound of it, as a WHOLE, xed
enough for my taste when the bands are in your mind.
crowded. Each time you hear this character,
I prefer lters which are 100Hz or 1
write it down. Pretty soon, youll pick
less wide when the going gets tough. it out every time its sent. Then add
These are more difcult to implement another character. Write them BOTH
at IF frequencies, since, for the same down whenever you hear them. Contin-
absolute bandwidth, the Q has to be ue until you can pick them both out.
higher. Back in ZL, Ive found that a Keep adding characters. After a while
ingly difcult to make the transition. Although it doesnt say so, the re-
Because I ve never practised the skill, ception test is based on the accuracy
I can only hard-copy reliably up to about of written copy, and the 5letter code
25 wpm, though I can read and compre- groups have to be transcribed in block
hend, without writing, much faster than capitals. The only real problem letter
this. But experienced old-timers like is the shortest in Morse terms E,
Bruce, ZLlADF, and Bill, ZLZBO, have which also happens to be one of the
copied me verbatim at 3540 wpm in most involved to draw. The option of-
longhand, although they say that the pen- fered by our Morse lecturer to any
cil nearly catches re. student with particular diiculty, was
However, an equally important skill to make the E with a curved stroke,
is to learn to read in the head, without encompassing the top, side and bot-
writing everything down. Most experi tom strokes in one movement (like a
enced CW operators only note details rather shallow letter C), followed by
for the log, and points they wish to re- a short horizontal dash in the centre. I
member or comment on later. Again, personally found this no easier than a
this ability has to be acquired. conventional block letter E, and
Our test requires hard copy, and thats what I always stuck to.
we get used to automatically making it, For handwriting, I can manage up
without bothering too much about the to around 30 wpm, as conrmed by
sense of what we have written. For head my greatly cherished RNARS Morse
copy, we have to simultaneously read Receiving Prociency Certicate.
and comprehend, and many of us have When I tried for the 35 wpm endorse-
forgotten how hard this initially seemed. ment, however, although I could read
What have other learners found? the Morse 0K, my hand seized up with
cramp after three or four words. Ive
always promised myselfId have a go
(Extracted and adaptedfor MM
using a typewriter, but the opportuni-
from Gary Bolds The Morseman
ty has never arisen. GCA
column in BreakIn, journal of
NZART various issues, 19881995)
G4ZPY
PADDLE KEYS
INTERNATIONAL
41 MILL DAM LANE, BURSCOUGH,
ORMSKIRK, LANCS., ENGLAND L40 7TG
TEL/FAX (01704) 894299
We thought we should remind you that, despite
our name, we dont just produce paddle keys!
As well as single and twin lever paddles and
combos, miniatures and keyers, we also make big,
beautiful pump keys like this ...
WASLKN
Pennes,
Dave
Photo/Collection:
Western Electric sounder, 1000 ohms. Very unusual design with a large
horseshoe magnet incorporated. Information requested
Davies
Wyn
Photo/Collection:
by
Sketch
Buzza Products key, made in Australia. The base looks like it was made to wedge into
a
specially shaped bracket. information requested by Lynn Burlingame N7CFO
PASCW
Spiering
M.
Dr
Photo/Collection:
2m,
'
19
Unknown Unit with 8-H Cotel key(?). Base marked SCOBA UNIMOHS AEL 2712. Inside
cover marked EDDYSTONEFlADlO 9902M. Information requested on use of this unit; plus
details of what should be connected where to get it going, whatever it does"
TOPS
Regarding the origin of the name the WFSRA around 1937, before I
;
thing like this: In the real telegraph I enclose a copy of a letter which
l
ofce the Chief Operator was shows the way Phil ran TOPS. I was
1
CHOPS, but the best operator was just another member of the club but
;
Im pretty sure that Arthur Bird lead one to think I was long-time
G6AQ, who founded and ran the
personal friend.
WFSRA, was a minister (The Rev Bob Eldridge VE7BS
Arthur H. Bird) and I think I joined Pemberton, BC, Canada
(rors TL? 87
Membership N"b"1w.r.s.R.A.
"
W. F.S.R.A.
mung (Muir. W.F.S.R.A.
operated by
Cecelia) seal.
on C.W. is elected a Member of the above Club.
Signed :;c(2;\;ccnw5
athleculcry 4' Tcpl " lubi
. CW5WJ.
" Wulrm " Helidrn Faad, rtrtnlyn, Ilalrh V/nlex.
Inside the box, which measures since this signal is already used for
52mm W x 117mm D x 44mm H, are a understood or understanding, at least
capacitor and a 3.3kQ resistor. The left in Continental Europe. Incorrectly
Golden Section key (see MM40, looked fair, 1 reduced the length
p.45), I have constructed a conven- and width by 13.5 percent (a Golden
tional contact key following the same Rule gure). I think the result is quite
principles, to demonstrate its versa l
G-QRP Club
The G-QRP Club promotes and encourages low-power operating
on the amateur bands with activity periods, awards and trophies. Facilities
include a quarterly magazine, Morse training tapes, kits, traders' discounts and
a QSL bureau. Novices and SWLs welcome.
Enquiries to Rev. George Dobbs G3RJV, St Aidans Vicarage,
498 Manchester Fload, Rochdale, Lancs OL11 3HE. Send a
large s.a.e. or two lFtCs
\czg. ll/[0mm BACK ISSUES Limited stocks of Issues Nos. 26, 27 31, 32, 33, 34, 35,
, Morse
36, 37, 38,39 & 40 ONLY now available, price 2.20 each to UK addresses;
Halli-fill E240 to Europe or 2. 75 elsewhere by airmail (less 20% for 3 or more)
IARU 37
N
World QRP Day 1995 lARU 39
Index to issues Nos 35 40
AIR FORCE
August 1994 to June 1995 RAF Operators (Itr) G. Armstrong 37 47
RAF Operators (Itr) J. Worthington 38 46
SUBJECT/TITLE AUTHOR/ORIGIN RAF Operators (Itr) B. Eldridge 39
(BC = back cover. C = inside back cover) Sorry Grace! (Itr) J. Barker 40 41
W/Ops or Signallers? (Itr) D. Byme 35 43
ABBREVIATIONS & PROCEDURES W/Ops or Signallers? (ltr) R. Prosser 36 43
Distinctive Tone (Itr) B. Eldridge
Distinctive Tone (Itr) J. Worthington AMATEUR RADIO
Distinctive Tone (ltr) M. Pouw-Amold EA-QRP Club tojoin EUCW EUCW N
Don't Understand! (ltr) R.Q. Marris Future of Amateur & Commercial Radiotelegraphy
Dont Understand (ltr) D. Leak F. Maia
Erasure Signal (Itr) R. Prosser I-QRP Club formed l-QRP Club
Erasure Signal (Itr) Various Joe Kelly Memorial Award Dundee ARC NOSQCDCD
Erasure Signal (Itr) G, Wonnald Krenkel, E.T., 90th Anniv Radio Magazine .1.
Various 40 40
P.S. 213A Key Various 35 42 Samson ETM-SQ Twin Paddle T. Smith 38 67
Morse Q15
V .
Alton Morse
GM&.0
Telegraph
ICG Club
W.K. Dunbar
1101 Maplewood Drive Normal. IL 61761
McLean County U.S.A.
WBZLLH
JOHN H. DROZDOHSKI
15 COLEMAN Rom
EAST Bauusmcx, N.J. 08816
MIDDLESEX COUNTY
U.S.A.
Working
I .IsInnce
.
of
F lEluerreit. Current~
~
\uLl'SCuilx hlIllInnIpcres
Ohms. Milliuinprcs Mini- Maxi-
lntllll tnutn
6
Non-polarlsed B . . . 400
Siemens . . . . . 400 H3 15 20
Sounder (20 shunted with 500.
Used for local circuits only) . lg'z 93 60 80
DiICIt Inkcr (including galvuno-
meter, 30 ) 330 4'9 15 20
and
[Spch of slip between 6
7 feet per minute.]
Local Inker (40m with 500 shunt) 37 (,9
Automatic lxeceivers . 200 I0 - --
lIelny . . . . loo 6 t6 -
Table of Working Currents of Post Office Instruments. Figure of Merit' is the minimum
current with which the instrument is expected to work when tested before issue from Stores.
The working currents give figures to be used when calculating for battery power.
From Telegraphy by WH. Fresco and J. Sivewright, published by Longmans, Green a Co, 1895