1911 six
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ITALY.
as “PA”; 1,400-metre wave is
1,500-foot wave is being reintroduced in Navy, it is known
known as * XX” or “ LL.”
TURKEY.
of W.T. stations, and the
It is proposed to link up, the Turkish Empire by a network
1911, at Constantinople, and have
Marconi Company are to erect a 20-kw. station by November
1} kw. sets.
fitted up 11 warships, four with 3 kw. and seven with 24 kw. spark sets They have never
The two German battleships use the old Telefunken
been retuned, and have the German double aerial.
The service wave 1s 600 metres.
Turkish characters used, other signals not understood,
Personnel very ignorant and incapable.
U.S.A.
W.T. in US, Navy :—
General Remarks, ;
duties, under the charge of the
Personnel.— Usually four electricians, who do no other
navigating officer, who has very little knowledge of W.T.
at Portland :—
Call signs.— The following call signs were used
Connecticut, NDQ. Louisiana, NJB.
Michigan, NJZ. South Carolina, NSW.
Delaw are, NIK. Kansas , NQO.
New Hamps hire, NME.
North Dakota, NMO.
Culgoa, NDU.
and the operators
Organisation —There seemed to be no organisation as regards wave-lengths,
were continually altering their receiving adjustments.
ve, and was rendered insensitive
Apparatus.—The receiving gear was sensitive but not selecti
by strong signals, Nv silent cabinets were fitted. Telefunken apparatus being arranged
No standardisation of arrangements was attempted, the i. :
as convenient.
No large aerials were used.
K 2
36
Connecticut.—Aerial, six single wires, between masts.
W.T. office on upper deck. Power 2-3 kw., 600 volts, frequency 60. Set similar to
Mark 1*.
Tuning is done by an ammeter in the aerial.
North Dakota.—Aerial, six single wires, and extensions fore and aft.
W.T. office behind armour. ‘lelefunken’s latest quenched spark. 5 kw. Irequeney, 500,
250 volts.
Tuning as above. On full power, ammeter registers about 30 ampéres. Receiving is
ordinary Telefunken.
The set mentioned in “W.T., British and Foreign, 1910,” page 47, has been landed as too
cumbersome .
Louisiana,— Aerial, four single wires between masts.
W.'T. office on main deck. Set as for Connecticut.
South Carolina.—Aerial, four single wires, and extensions fore and aft.
W.T. office inside main mast. Installation identical with North Dakota, Designed wave-
length 1,000 metres, but 500 metres usually employed.
Delaware-—Telefunken gear is used, the whole apparatus having been installed and tuned
by the Telefunken Gesellschaft.
The Fessenden system is used in the following ships:—Scout cruisers “ Birmingham” and
“ Salem.” 12 k.w. Daylight range 600 miles, It is proposed to replace these sets with less
powerful sets, The gunboat “Paducah,” and the destroyers “Smith” and “ Roe,” have 2 kw.
sets. Nineteen further sets are on order. A 25-kw. set is at Key West. A 100-kw. set is to be
installed at Washington, with a guaranteed range of 3,000 miles.
Two kw. sets are working successfully in several vessels of the United Fruit Company.
with Key West, 924 niles, when atmospheric conditions
— A. 25-kw. set communicates
Colon,
are favourable.
W.T. Communication in the Philippine Islands.—The U.S. Government is considering proposals
10-kw.
for introducing W.T., communication throughout the Philippine Islands, by installing six
stations, to be supplemented later by a number of 1-kw, stations. In considering the system to
spark
be employed, Captain Wildman, of the U.S. signal corps, strongly recommends a quenched
system, which he says is undoubtedl y the best arrangement . He states that the Telefunken
can be
wagon set, using quenched spark with a frequency of 509, gives a clear singing note that
easily read through atmospherics.
Urueuay,
A system of Telefunken stations is bemg established in the Republic, but as yet none of the
stations are completed. The cruiser “ Montevideo,” and the gunboats “18 de Julio” and
their apparatus arrived at Montevideo in March 1911. ‘The
‘‘ Oyarvide,” are to be fitted, and
The
high-power station at Punta del Este has been approved, and an estimate of 55,000/. accepted.
(1,000 kw.) is proposed for this station for the
site is not yet fixed. An extra high power
following reasons :—
(a) Punta del Este will have to work at great distances as compared with Clifden, as the
following table shows :
Punta del Este to Coltano - - - - 5,950 miles.
» » 99 ng,: Clifden 7 - - - 5,700 .,,
» » 593 «95 «Glace Bay - - = - 4,860 ,,
Clifden to Glace Bay — - - - - - 1,940 ,,
. % 3, Cape Cod - - - - - 2,430 ,,
, Coltano to Cape Cod - : - ~ - 3,400 ,,
(b) Clifden, for working across the Atlantic, has a 400-kw. station,
Difficulty is anticipated in sending messages across the forests of Braztl,as has already
(c)
been experienced between Para and Pernambuco,
(d) Increased wave-length as compared with that of Clifden.
Mr. Berry, the manager of the Marconi Company at, the River Plate, which is erecting the
station, has stated that Mr. Marconi, during his recent visit to Argentine, informed him that if,
after the installation of the 1,000-kw. apparatus at Punta del Este, experiments were satisfactory,
the power of Clifden would be increased also, adding that he was already in possession of land for
the purpose.
FALKLAND ISLANDS.
It is proposed to erect a station to communicate (chiefly at night) with Punta del Este.
Five kw. two masts. Wave-length 2,000 metres. Position of station undecided.
Brazis.
1. The station at Fernando de Noronha is working, December 1910.
Aerial.—Four 75-metre towers at the corners of a square of side 125 metres.
Slightly directional for S. W.-N.E. for Rufisque (near Dakar) and Levrier on the African coast.
37
Power, &c.—Six hundred metres wave, up to 4 kw., range said to be 400 miles.
One thousand six hundred metre wave, up to 35 kw., range said to be 1,000 miles.
Power from 60 H.P, motor, working a D.C. dynamo and alternator on the same shaft.
Accumulators of 300 ampere hours and a small alternator for short distances are also used.
Transformers.— Step-up to 60,000 and 80,000 volts.
Condensers.—Gaiffe type, aluminium and glass.
Receivers.—Ferrier type, mercury and platinum in acidulated water.
_ 2, A 1,000-mile station at Rio Grande de Sul has been approved, and a similar one at Cape
Frio is projected.
BELGIUM.
CGR (Brussels), using U tune, heard communicating with Lepel experimental station at
Slough.
HoLLANb.
SCH has been heard working with Dutch cruiser “ Jacob van Hanskerk.”
ARGENTINE.
Several stations have been erected down the cast coast.
The following are working :—
Cape Corientes. Ushuaia,
Cape Virgins. Mendoza.
New Year Island.
Eeypr.
Port Said, Lloyd’s signal station, call LPD. Marconi system. Wave-length Q. Radius
50 miles.
Port Tewfik, Lloyd’s signal station, call LPK. Marconi system. Wave-length Q. Open
all hours.
Russra.
Call of Khivinetz is W8.
NEWFOUNDLAND.
Mareoni Station at Fort Amherst, St. Johns.—An experimental station has been erected at
Fort Amherst to ascertain whether better results could be obtained there than at Glace
Bay, as it is intended to erect trans-Atlantic stations at Fort Amherst and Petty Harbour, six
miles to the southward, if the Government permit. One station will be for transmitting, the
other for receiving.
Observations with regard to atmospheric disturbances, &c. are in progress, and so far it seems
that atmospherics throughout the bay are steady, but at sunrise and sunset there is a dip and a rise
in the atmospheric curve.
Spain.
The high-power station at Madrid (call sign MAD) uses a high clear note on wave-lengths of
about 3,200, 4,750, 6,500, 8,000 feet. he first three are used with Ceuta and Melilla stations.
The 4,750 wave is also used for signalling to men-of-war, the latter replying on a 2,000 feet wave.
The 8,000 feet wave is used for commercial work, &c. <A four-figure cypher is often used in
Government messages.
Another high-power station, perhaps Cadiz, call sign MCP, has been heard on a low musical
note, wave about -X tune.
The following military stations have been heard :—
Station. | Calls. Power. Wave.
Alcazar - - - ALC, EC3, YA Low 3,200 feet.
Almeira - - - ALM, FAL Medium »
Ceuta - - - CEU, EC9, ALY " ”
Melilla - - - MEL ” :
Larache - - - EC10, MOL Low ”
Casablanca - - CP — 4,000 feet.
Fez - : -, FZ | — ”
>. 7 - - RGE
|| — ‘ |
|
i
A “singing spark” is used, with 8 gaps, which can be short circuited separately to reduce
the range. Power is supplied at 500 cycles by a motor alternator with automatic starter,
the generator being of 4 kw. at 220 volts. A hand-worked key is used. The current passes
through an impedance coil with an adjustable iron core sliding in and out, and the voltage is
stepped up to 13,000 by an open-core transformer. The primary capacity is made up of large
leyden jars ; total capacities of 028 or *036 microfarads being used.
‘ha
38
The perikon detector, with Wireless Speciality Company’s receiving gear complete, is used;
and the pyron detector is used for short ranges. The latter is said to be stable, but rather
insensitive.
The Telefunken supply a detector of silver pyrites and brass wire ; it is said to be difficult
to adjust, and not as sensitive as the perikon. They also supply a detector containing silver
filings in a short glass tube, from which the Americans have never been able to obtain satisfactory
signals.
The send-receive switch is a hand-worked high-tension switch, which, when put to “ receive,”
stops the spark gap fan and breaks the generator field to prevent singing in the telephones.
The office is wood lined to prevent noise, and all leads in primary and aerial circuits are of
stout copper strip about 1 inch wide.
The ship does not carry a wavemeter, tuning curves being supplied by the company.
BELLINI-TOSI DIRECTIONAL SYSTEM.
(See Annual Report, Appendix, 1907, p. 61, and 1909, p. 54.)
This system has been on trial in the French Navy, and it appears that the relative bearings
of ship-and-shore stations at distances up to 12 miles can be located to within about 4 degrees, but
no definite reports of results over longer distances have been received. The results were obtained
by using suitable aerials in conjunction with a “radiogoniometer” at the receiving end. The
radiogoniometer consists of two fixed coils and one movable coil (see Annual Report, 1907, p. 61),
the bisector of the angle between the positions of the movable coil when weakest signals are
obtained indicating the direction of the sending station.
For directional transmitting purposes, a radiogoniometer in conjunction with suitable aerials
is used at the transmitting station.
SPARK PHOTOGRAPHY.
The following extracts, taken from reports by Captain R. ff. Willis, R.M.I.1, on his
system of spark photography, are considered to be of sufficient interest to be given in extenso :—
AN ACCURATE METHOD OF TUNING COUPLED OSCILLATORY CIRCUITS BY
PHOTOGRAPHING THE PRIMARY SPARK TRAINS.
The enlargements shown in Plate XII. are photographs of trains of X wave-length primary
sparks, and illustrate the degree of certainty and accuracy with which the tuning of the primary
and secondary circuits can be checked.
The definiteness of the blank interspace between the commencing half group and the
succceding whole group of sparks in a train is a measure of the accuracy of the tuning, and it
will be seen that when the sparks are not accurately in tune the blank interspace merges into the
spark groups on either side.
The photographs lettered A, B, C, and KE were taken under high-speed conditions, and those
lettered K, M, N, and O under slow speed conditions, the latter speed being approximately one-
ninth of the high speed,
The distance between the primary and mutual coils was kept the same for all photographs,
the only alterations in the circuits being those made on the aerial coil, as shown in the following
| . Part ofa Tun added or . Definiteness of
Speed, Laktet taken off Aerial Coil. = Mics. Blank Space.
a essprmzecacs u x eee — a
| A + Two-sixths. + 24 Hardly defined.
Hich 7 ; - i B + One-sixth. + 14 More defined.
sd | Cc Correct tuning. _— Well defined,
| E — Two-sixths. — 22 Hardly defined.
K + Four-sixths, +5 Not defined.
- - - M + Two-sixths. + 24 , More defined.
Slow
N Correct tuning. — Well defined.
| oO — Two-sixths. — 24 , Less defined.
Note.—The aerial capacity is 154 jars.
i wi be noted that, except for speed, A corresponds to the conditions of M, also C tu N,
and Ik to O.
The edge of each film was divided off into 4-inch intervals, so that the extent of the enlarge-
ment could at once be seen.
INDUCTION CURVES FOR AERIAL AND MUTUAL COILS.
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SPARK PHOTOGRAPHY.
To face page 3°.
Prate XIII.
SPARK PHOTOGRAPHY.
COWPLINGH
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To face page 39,
Photographs taken at one-sixth turn distant from the correct tuning position at slow speed
not show any appreciable difference (and so have not been
do
included), and therefore it will be seen
that high-speed photographs are somewhat more sensitive to accurate tuning, although
it is found
in practice that by taking a series of five photographs at slow speed with one-third turn
alterations,
the above and below tuning photographs can be easily matched, and that the mean
adjustment
gives the correct tuning position as accurately as under the high-speed conditions;
also, under
slow-speed conditions, twice as many photographs can be taken within half an hour owing
to the less
time occupied in speeding up and stopping, and nine times as many specimen trains
are obtained on
the same length of film.
It is not suggested that this method of tuning should take the place of the wavemeter,
but
having once found the approximate adjustment by means of the wavemeter, then a series
of
could be taken in order to get fine adjustments ; and after this it would only be necessary photos
to take
one photo at weekly or monthly intervals and, by comparing it with the original series,
it could
at once be discovered whether even a very slight alteration had taken place in the wave-length
of either circuit; over one dozen specimen spark trains are obtained on each high-speed record
(when the spark-train frequency is 500) and nine times this number on a slow-speed record.
By counting, it will be seen in B and C photographs that there are 334 sparksin the first
half
group of the train, which tells us that the coupling percentage is 100'334 = 8 per cent., and this
appears to be a very ready and accurate way of determining the coupling percentage.
At high speed only loose couplings of 3} per cent. and less are sensitive to
the difference
of 1 inic in the aerial inductance.
It has been found that tight couplings require several mics added or taken off
before any
difference can be detected.
Tuning with the wavemeter, using a 5 per cent. coupling and varying the adjustmen
ts on to
aerial coil from a half turn up to a half turn down from the correct tuning position, the
double readings obtained in every case lies within ++ 4° of the mean reading of the mean of the
correct tuning
position, therefore it is a very easy matter to be a whole half-turn out of correct adjustment when
using the wavemeter, but impossible when using the photographie method, where permanent
records are obtained, and these are always available for inspection and comparison,
DousLe-sparK PHOTOGRAPHS.
Plate XIII. shows enlargements of photographs of double trains of sparks, i.e., primary
secondary trains of sparks photographed simultaneously on the same film, and and
the effect of
gradually loosening the coupling is visibly demonstrated.
A small spark of 14 mm, was inserted in the secondary circuit and a spark of 8 mm. used
in
the primary : wedge-shaped spark plugs being used in each case and subjected to a strong air
blast,
so that the trains were not excessively prolonged.
X wave-length was transmitted, which gives a spark Jrequency of approximately 200,000
per second,
The edge of each film was marked off with 4-inch intervals, so that the extent of the enlarge-
ment could at once be seen.
The coupling percentages work out as follows :—
—. No. 1. | No. 2. No. 3. | No. 4. No.5,
No. of sparks in the first half- 83 113 | 163 203 303
group of the primary train. |
No. of sparks in any one 17 23 33 | 41.
whole group of the primary
61
|
train. |
The coupling - - - 200/17 200/28 200/88 =| 200/41 200/61
Percentage - - - - | 11°8 per cent. | 8°? per cent. | 6-1 per cent. | 4:9 per cent. | 3-3 per cent.
The last photograph shows double trains of sparks of the same coupling percentage as in
No. 3.
Neither the negatives nor the prints, from which the plates have been made, have been
retouched in any way whatsoever, as this would destroy their interest and value,
ANALYSIS OF TENDERS FOR W.T. INSTALLATION.
The following information with regard to tenders for W.T. installat
ions by the principal
commercial companies is of interest as showing the prices and conditio
ns specified by the various
firms, and it will be noticed that the prices of similar service installat
ions would compare favourably
with those quoted.
i e4
ANALYSIS OF Provisory TENDERS RECEIVED.
es ; Cost, Wave-lengths Wave-lengths
| . in , Power, Kilowatts. Pounds sterling. ‘Transmitter. Range, |
Receiver. | Kilometres. |
aun and Total Cost | —~ a SSS — S| = ri = Musical Note. | ' Type of Receiver. Delivery.
Ss | LM | su] os. | LM.) SM. fo 8 | GM.) SM. fos | tat i SM. 8. | TM. NM, |
a ieee ieee — | i) oe || i
| Telefunken- -! 10 g 75 15,900 | 1,120 | 900] 600 | 300. 300) — 250 — | Guaranteed musi-
Sterling, 16,4167. 900) 450 450
Day. Selector type not | Delivery in 3 months.
f
to | cal note can), Not 600 -250to} mentioned. | Erection in 4 if pre-
| 1,200 | 600 600 » 3,000) over-read atmo- ‘stated.
| 300 | liminary work (e.9.,
| | 1,500 | 900 | I spehrics and | | lengthening masts) is
1,800 other systems | Night.
| carried out,
at present in|) Not id. 000 —|
| | | | use. stated.’ }
| United, U.S.A. - 5 2 | -5 13.040 | 1,120 | 820 | Not mentioned -| Not mentioned -| No gnarantee or |
| Sterling, 11,9402. Day Not mentioned - | Naval installations
eom-
| mention of — ° 600 100 pleted in 3 months,
| | ' musical note.
| |
| Night
| — 1400 250 |
Marconi - 20 | 3 1k 17,840 | 525 | 495 [2.400 300 300 fF — A_———~. | Guaranteed musi-' Day. Selector type stated Delivery.
' Sterling, 14 0001, { | , 600 600 100 to 2,500 cal note. ,1,.200 550 350] able to cut out | 1-14-kw. setin 14 mths.
| | | | !
| interference from | 1-3-kw., setin 2 mths,
j Night. atmospherics. | 1-20-kw. set in 5 mths.
| | 2.400 1,100 700 Erection.
| 1-1}-kw, set in 7
| | 1-8-kw. set in 14 days,
|
1-20-kw. set-in biel
Poulsen - - | 15 3 1 [8,450 | 1,650 |1,275 500 500 — 150 150 | 150 | Guaranteed six Day. Selector type stated | S. in 5 months.
Sterling, 23, 9751. to | to to to | to different musi- |1,500 ; 550 300] able to diminish | L.M. 4 months.
| ' 3,000 | 2,000 | 4,000 | 4,000) 2.500] cal notes. strength of atmo-!S.M. 33 months in-
| Night. spherics. cluding erection.
| | Not stated.
Lodge, Muirhead- | — | 3:5; — | — |1,000| — — ag | — .| Not mentioned ae
‘
Selector type. |
' —)| | —
i 3,000 | -
“sll |
| =
Night.
| a |
— = —
Ty \
‘4
a | to 4
: 000 :
i