1911 two
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10
BUZZER REPEATER IN LIEU OF INKER RECORDER.
It having been decided that no more Inker Recorders would be purchased (N.S. 6186/10466
of 20,7.11), it was found necessary to provide some instrument which would take the place of
those mentioned on page 15 of last year’s Annual Report.
It has been ascertained that a Patt. 1301 telephone receiver gives a loud clear note when
joined across the terminals of the Mark II. or Mark I*. impedance coil when using the main
installation, or across the bobbins of the buzzer transmitter when this form of transmission is in
use. Taking advantage of this fact a buzzer repeater has been evolved whereby signals are
automatically repeated on the bridge and in the signal house of the transmitting ship.
By means of a change-over double pole switch in the W.T. office, it can be arranged that
the buzzer repeaters, placed in the signal house and on the bridge, are caused to respond to the
working of the sending key for either method of transmission. By means of a switch placed
close to each repeater it can be silenced when not required, and a lid, which works on hinges,
can be used for regulating the amount of sound given out.
It has been found that anyone touching the terminals of the buzzer repeater might, in ships
fitted with Mark II. installations, receive a severe shock if the repeater was connected directly
across the impedance coil ; the addition of a small transformer, comprising two similar coils, and
therefore having unity ratio of transformation, has therefore been instituted for those ships.
These transformers are so designed as to be capable of being secured to the cover of the
impedance coil terminals.
A third buzzer repeater will be supplied for use in connection with the short distance
sets in some ships not already supplied with inkers.
Radiation Gauge.—This instrument has been devised to give an indication of the amount
of current in the aerial, i.c., to show the radiating power of the aerial. It also serves to show
that the aerial is receiving the correct amount of power, thereby acting as a check on the
adjustments, and an indication that the transmitting instruments are correct. It consists of a
low reading hot wire voltmeter having a resistance between terminals of about 2-5 ohms, and a
full scale deflection of about *7 ampére, so designed as to obtain as dead heat an action as
possible. One terminal of this instrument is earthed to the metalcasing. The voltmeter is to
be hung inside the cage in such a position that the scale, which is marked in arbitrary divisions
only, is fully visible to the operator in the silent cabinet. With the voltmeter is supplied an
adjustable shunt, which is arranged to be connected between the earth terminal on the earth-
ring fitting, and earth, in the place of the metal strip at present supplied for that purpose, The
connection between the shunt and the voltmeter is to consist of a length of Pattern 7984 lead-
eased cable, the lead casing acting as one conductor. The shunt will require to be so adjusted
that a full scale deflection of the gauge is obtained when transmitting at maximum power on
“Q” tune. Only a slight flicker of the gauge will show when sending “ D” or “ P,” even when
the full amount of shunt is used; no deflection at all will be cbhtained when sending on buzzer
transmitter, though this can be remedied in that case by substituting an inductance of about
10 mics for the present shunt. The gauge’ is fitted with a fuse and spare fuse, together with a
reel of fuse wire.
It is proposed to make the addition of a radiation meter to the destroyer installation, in
order to afford an immediate indication of any defect in the circuit, and to assist tuning. To
make the radiation meters types 1 and 2 suitable for this purpose it will be necessary to
substitute a single turn of wire, having an inductance of about 1 mic, for the adjustable portion
of the shunt.
SERVICE MARK II.
IMPROVEMENTS.
Switch, Two-way, for protecting Circuit, Type 1.
When working with the “ Buzzer” transmitter, it has been found that the action of the
protecting switch is tuo slow to protect the detectors efficiently, owing to the delay caused by the
inductance of the magnetic key bobbin which is in series with it. The above-named switch has
therefore been introduced so as to cut out the magnetic key when sending with the “ Buzzer”
transmitter, and to substitute for it two 50 c.p. lamps in parallel as a resistance,
(G. 7858/11, G. and T. Orders, May Ist, 1911.)
IL
INKER RECORDER.
The inker recorder referred to on page 15, W.T. Appendix, Annual Report, 1910, is found
to be of but little use at sea, and has therefore become obsolete. (See page 10.)
EXPERIMENTS TO IMPROVE NOTE.
In continuation of the experiments described in Appendix to Annual Report, 1910, page 35,
further trials were carried out on the Mediterranean station towards the end of 1910, with a view
to improving the note.
Additional impedance coils, from ‘4 to *23 millihenries, were tried in conjunction with the
special spark phigs previously described. It was found that, other things being equal, an increase
in the apparent power factor of the alternating power supplied to the transformer gives an
increased range, and also that neither the frequency nor the coupling appreciably affect. this
power factor. Owing to the arcing which takes place, the power factor diminishes as the voltage
is raised with a given spark length. This, however, does not decrease the range, but rather
increases it owing to the higher note, although an excessively high voltage may cause arcing
which will spoil the note and so again reduce the range.
The combination of the extra impedance coil and the special spark plugs produces a higher
aud clearer note, increases the strength of signals, and reduces the strain on the alternator.
The aerial brushing has been eliminated by fitting multiple feeders containing up to 40 parts
of wire.
With this arrangement daylight range between “ Nxmouth” and St. Angelo was increased from
abont 500 to 650 miles, when using a spark length increased by about 75 per cent. This increased
spark length no doubt reduced the arcing, and it has been recommended that a more powerful
blower be tried so as to still further reduce this arcing.
(2) “D” anno “P” Tunes—sBest Meruops OF TRANSMITTING.
In accordance with the report of the Wireless Telegraphy Conference (vide Annual Report,
W.T. Appendix, 1910, page 8), a series of experiments have been recently carried out between
the “ Vernon” and “ Velox” to determine the following points :—
(1) The best arrangement of the Primary Oscillating Circuit ; and
(2) The best arrangement of the aerial circuit.
Primary Oscillating Circuit.
Three arrangements were tried for sending “ D”’ tune from Mark II. sets, viz. :—
(a) The main Mark II. condensers were out out by removing the series-parallel clips, and
20 Leyden jars (10 in parallel and 2 in series) were connected up across its terminals.
Rough resonance was obtained by the use of the extra impedance coil. Otherwise
the circuit was the same as that used for the longer waves. It was found that not
more than about 6 mm. spark could be used without puncturing the Leyden jars,
and the range was only moderate. This arrangement was therefore discarded.
(4) With a view to increasing the capacity of the circuit, a destroyer’s oscillator and con-
denser (capacity, 17 jars) were next tried. The spark gap was specially fitted with
an air-blast, and the arrangement was joined up to the secondary of the Mark II.
transformer. Owing to the excessive sparking at the top of the spark gap, not
more than about 5 mms, spark could be used. Although possibly the range was
slightly better than with the arrangement described below (c), it was not considered
satisfactory, in view of the large amount of space taken up by the condenser,
complication in the air-blast arrangements, and the expense of providing every
Mark II. set with a specially-designed condenser and oscillatur somewhat similar to
those supplied to destroyers.
(c) A special condenser was then constructed, having a capacity of five jars, consisting of
five sections in series; each section was built up with 12 sheets of ,, inch ebonite,
connected in parallel as in the Mark I*. condenser. The condenser was supported
in a frame which hung from the upper flange of the main condenser tank, and was
secured in that position by three of the butterfly nuts which secure the cover to the
tank, The terminals of this condenser were connected to the terminals of the main
condenser by 4 inch copper tubes, the actual connection being made to suitable
terminals sweated to the top of the condenser safety discs. The remainder of the
circuit was the same as that described in (a) above. <A spark of 18 millimetres was
used, and the range was very nearly as good «s with the (b) arrangement. The
condenser only projected about 6 inches from the side of the main tank, and might
be left in position when sending on the longer waves. This appears to be the most
suitable arrangement, and a condenser is now being designed on these lines. It
will be suitable for sending on either “D” or “P” tunes. With the extra
impedance coil (as described in G. and T. Orders, June 1909), approximate
resonance was obtained at a frequency of abont 360 cycles,
Bi?
12
Aerial Circuit, “ D” Tune.
The harmonic principle has been adopted since it appears to give rather better range than
any other method, and has also certain other practical advantages,
The principal disadvantage of the harmonic method hitherto has been the fact that it not
only transmits the harmonic wave, but also sends out the fundamental wave with sufficient strength
to interfere with ships within a mile or so, which are receiving on approximately the same wave
as this fundamental. This defect was overcome by first tuning the aerial to a wave-length of
about 1,400 feet, by placing a condenser in the earth lead, and then forcing a 700 feet harmonic
wave into this aerial by placing a second condenser in parallel with the mutual coil,
To tune—(1) Disconnect terminal K and tune aerial to 1,400 feet.
Do not disconnect large inductance.
(2) Insert a spark gap at 8.
Connect terminal K and tune circuit K, G, 8, C, to 700 feet,
Tan
Do not disconnect aerial when doing this.
The arrangement is shown in the abuve sketch, in which A is the aerial coil, B is three
Leyden jars connected in parallel, C is two or three Moschicki condensers as required, also joined
in parallel. These condensers are all contained in a small Leyden jar box, D; G is the mutual
coil, and E and F the earth-ring fitting and the operating switch respectively ; H is an induct-
ance of approximately 15,000 mics. The Leyden jar box is slung with insulating cord from the
bottom of the aerial coil. The range with this arrangement was found to be at least equal to that
obtained when the aerial was tuned to a fundamental of 2,800 feet. The interference caused by
this set’to a ship 3 cables away, and receiving any of the longer waves, could be easily cut out,
The adjustments of this set for receiving are the same as when using a special small aerial, A
destroyer receiving from this set requires the same adjustments as when receiving from another
destroyer. At 90 miles, a destroyer fitted with C type gear, received signals sent by this method
at strength 10 by day.
It may be found in emall ships that the natural wave-length of the aerial is not more than
1,400 feet, and in this case the Leyden jar condenser can be dispensed with. In all cases,
however, the aerial must be tuned to about 1,400 feet.
Aerial Circuit for “P” Tune,
Since the fundamental of an aerial tuned to a harmonic of 1,000 feet is bound to interfere to
a certain extent with ships looking out on 2,000 and 4,000 feet waves, this method of tuning is
considered undesirable for sending “ P.” Instead of the above, a condenser should be placed in
series with the aerial to reduce the latter to 1,000 feet. The Moschicki condensers used for “D”
tune would probably be suitable for this purpose.
Mark 1®,“ D” and“ P” Tunes.
The same arrangements for the aerial are recommended for Mark I*.
MULTIPLE FEEDER &
ANTIBRUSHING GEAR.
BRANCH FITTING AND SPREADER CONE
SPREADER DISC SPREADER RING
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COUPLING NUT SCREW LONG SCREW SHORT
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Deck _
REFERENCE,
CROWN OF WIRELESS OFFICE
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DECK INSULATOR
COUPLING NUT FOR FEEDER
Armoured
Deck
| SCREW LONG FOR FEEDER
SPREADER CONE AND SPREADER RING
SPREADER DISC AND SPREADER RING
SCREW SHORT FOR FEEDER
RECEIVING WIRE
BRANCH FITTING FOR FEEDER
SLOT AND BOLT FITTING
POLES FOR EQUALISING STRAIN ON AERIAL WIRES
yA
IMPROVED FORM OF AERIAL FEEDER.
(See also A.R., p. 31, 1910.)
The design of fitting for this form of feeder is practically complete.
The feeder will consist of a tube 5 inches in diameter, made up of (probably) 40 parts of 21
L.S.G. enamelled wire. ‘This tube will run between the deck insulators in ships which have the
W.T. office below. The same form of feeder will be continued for the first 20 feet or so above
the upper deck insulator ; the feeder will at this point divide into two parts of 20 wires cach,
the division being effected by a branch fitting. The 20 wire tubes will run to the aerials, the
connection to the latter being made through a slot and bolt arrangement, special care being taken
to divide the strain equally among the various parts of the aerial.
The wires are kept in cylindrical formation by means of “spreader discs” and “spreader
rings.” The former consist of copper discs approximately 5 inches in diameter, having a turned
down flange of half an inch, in this flange 40 grooves are worked at equal intervals round the
circumference. The “spreader ring” consists of a ring having an internal diameter of 5 inches
and cut from } inch copper tube, the edges being well bevelled. The feeder wires are fitted in the
grooves of the “ spreader discs” and are held in place by the spreader rings.
The connection of the tube to the deck insulator or to the branch fitting or aerial connection
is effected by means of fittings termed “spreader cones.” These fittings are arranged with
40 grooves similarly to the “‘ spreader disc,” the wires being held in place as before by “ spreader
rings.” The feeder wires, after passing under the spreader rings, are bared and sweated to the
suriace of the spreader cone, one wire being left sufficiently long to act as a receiving connection.
The smaller end of the spreader cone is fitted with a gunmetal casting which is sweated and
rivetted to the coppercone. This casting acts as a bearing surface for the deck insulator connection
(known as “screw short” or “screw long”’) or for the bolt of branch connection. The “screw
short” or “ screw long” passes through a 4 inch hole in the copper cone. In the case of the
“ between deck” fittings it is necessary to have an arrangement to take up the slack caused by the
stretching of the feeding wires. For this purpose “ coupling nuts,” into which fit “screws long,”
are provided. The “coupling nuts” screw on to the “ between deck ends” of the deck insulators,
and into these nuts are screwed the “screws long,” the other ends of the “screws long” fitting into
the spreader cones.
Each “screw long” allows of 3 inches adjustment, and as a “screw long” is fitted at each end
of each “ between deck ” portion of the feeder, the total adjustment of that portion is 6 inches.
The upper bolt of the upper deck insulator is fitted with a “screw short,” no adjustment of
length being here necessary.
A cover is supplied to fit into the base of the copper cones to prevent water, &c. from
accumulating therein; drain holes are also drilled through the gunmetal seating of the copper
cones.
In aship having three deck insulators, the following fittings would be in place when using
the new feeders with a Mark II. aerial consisting of two main parts and two after legs.
Article. Number. Remarks.
Coupling nut - - - Two to each deck insulator, except the connection in the W.T. office.
ROH ox
Screws long - - - Upper s'de of upper deck insulator.
Screws short - -
Branch fittings -
Aerial connections
Spreader cones 16
Spreader ring - - - 164*
Spreader disc - - *
i
The receiving connections are not sufficiently good with the above arrangements, and in
order to reduce the resistance, one or more wires have to be left sufficiently long at each cone
feeder to connect directly to a cable eye placed under the nuts of the deck insulator or under
the heads of bolts placed in the branch fitting.
The wire used for the feeders will be single strand wire of 21 L.S.G., the wire being
insulated with enamel; a first supply, suthicient to fit “ Vernon,” “Furious,” and two ships at sea,
has been purchased. When these fittings are supplied, information will be obtained as to their
behaviour in a sea-way, wind-holding effect of the tubular feeders, liability of receiving wire to
be burnt out when sending, &c., and from the information thus obtained any necessary modifica-
tions will be introduced and the fittings then supplied to all Mark II. ships.
#* Allowance of spreader discs has not yet been settled; it will probably be about one to every 4 feet of
feeder, Spreader rings will be supplied, one to each spreader disc and one to each spreader cone, The above
allowance does not include spares, the necessary proportion of which will be determined from the reports after
trial at sea.
B3
14
Exrracr rrom Report or “Exmoura” on TRIAL oF Muuriene FREDERS.
Ship. Aerial. Feeder.
“Hxmouth” - - - - | Ordinary Service Pattern - - - | Two ten-fold cylindrical, Lowest part
of feeder 20-fold of 8 inches diameter,
“ Bacchante ” - - - - | Similar to “ Exmouth” - : - Do.
“Suffolk” = - - - - | Four parts between the masts noafter | Four ten-fold cylindrical.
legs.
St. Angelo W.T. Station - | Three parts between masts - - | Three ten-fold cylindrical, one to each
end and one to centre of aerial,
Lowest part of feeders 30-fold of
10 inches diameter,
N.B.—“ Aboukir” and “ Lancaster ” are fitting similar feeders. All ten-fold feeders are made
of Service pattern aerial wire with 4 inches diameter rings or } inch brass bolt staves as spreaders.
Elbow pieces are constructed of similar material, where sharp bends are taken in the feeders. All
reports state that brushing has been abolished. Both sending and receiving efficiency is noticeably
increased,
The “ Exmouth” and St. Angelo aerials have been exposed to exceptionally severe gales since
fitting the new feeders, and no trouble has been experienced.
“VERNON’s” Remarws on “ExsouTs’s” Report (12.5.1911),
The report is interesting and very satisfactory. The form of multiple feeder for which desiens
are now being got out in “ Vernon” will be of a somewhat lighter construction than those described
in the Mediterranean report, it having been found desirable to modify the original design in detail
to render it suitable for manufacture in quantities and more convenient for fitting.
DESTROYERS INSTALLATIONS.
The following destroyers have been fitted during the year :—
* Acorn.” “ Fury.” “« Minstrel.” “ Rifleman.”
“ Alarm.” “ Goldfinch.” « Nautilus.” “Ruby.”
“ Brisk.” “ Hope.” “ Nemesis.” “ Sheldrake.”
“ Cameleon.” *¢ Larne.” “ Nereide.” ** Staunch.”
“ Comet.” “ Lyra,” “* Nymphe.” “ Stour.”
“ Ferret.” “ Martin.” “ Redpole.” “Test.”
All these installations are working satisfactorily, This brings the total number of destroyers
fitted to 85,
The fitting out and wiring specifications for destroyers sets have been completely rewritten
and revised. A diagram of the system of wiring was given in last year’s Annual Report. This
new arrangement of office appears to be working well.
Exercise Transmitter,—This was described in last year’s Annual Report, page 18, W.T.
Appendix.
All the sets have been bought and issued. It has been found that the range obtainable is all
that was expected; but it has also been found that great interference is experienced by other ships
in the vicinity, the set being a “ plain aerial” set. It was observed that at a range of 2 miles it
interfered with ships receiving “ W” wave. The following modified method of connecting up the set
has given very good results. It has the advantage that a definite wave is cmitted, and the range
between destroyers using magnetic detectors is about 3 miles. It does not interfere with reception
by other ships in the harbour.
Fig. 1.
1,
deyden
Say
= AY on ML
hax
pa
= . ZL
To coil
_ A primary coil, consisting of seven turns of Pattern 611 wire, wound round the outside of the
winding on the aerial tuner, connected in series with one Leyden jar and the small spark gap on
the lid of the “ Box for Exercise Set” forms the primary circuit. The combined lengths of the
15
connections between the primary winding of seven turns, the gap, and the Leyden jar should
be, approximately, 1 yard. It is found that this arrangement is very nearly exactly ““D” tune. It
will vary slightly, of course, owing to differences in the Leyden jars and in the positions of the
leads; but it is sufficiently accurate for all practical purposes, and more exact tuning can then be
obtained as opportunity offers in the usual manner. The arrangement is shown in Fig. 1.
Fie. 2.
Note on the Adjustment of Coils,—\Vig. 2 shows the arrangement of interrupter in the small
coils. A, A are the platinum contacts, and B is a spring for keeping the armature off the pole
tip. The best adjustment is obtained when the contact screw C is eased fairly far back, and the
screw D (which puts more pressure on the spring B) screwed right down. As, however, the
cells gradually run down, it will be found necessary to ease up D and screw down on C,
When sending on power it is necessary to leave the “exercise primary” winding on open
circuit and disconnected from the jar and gap at the points A, A, Fig. 1. It should not be
short-circuited, and there is no necessity for it to be unwound.
Hand Operating Key.—-It has been found possible to force the lid of the box down on to the
top of the phosphor-bronze blade carrying the contact for the protecting circuit; that is usually
a live contact, and if there is an earth in the ship on the opposite pole, a burn out will result.
In order to avoid this it is advisable to secure a slip of micanite to the inside of the cover
over this contact.
Extracts From Rerorr py Commanper Payne, H.M.S. “Crusaper.”
Exercise Transmitter.—The new circuit for exercise transmitter has only been in use for under
two months. Results so far very satisfactory. Range between destroyers, 3 miles. No
interference with other ships at a distance of two cables.
Dennis Detector.—An extempore detector made up from details given in last year’s Annual
Report has been tried against the crystalite detector. It is more stable, and does not lose in
sensitiveness from sending or from strong signals from ships close by. It does not require
continual adjustment, and when once adjusted it remains sensitive for at least a month. It is not
quite as sensitive as a crystalite detector when in its best adjustment. °
SHORT-DISTANCE SETS.
It was approved as a special instance to supply the “ Neptune” with a short-distance sect
(G. 20429/10).
This set has been fitted and is in use.
It has also been approved as a special instance to supply the “ flercules”? with a short-distance
set (G. 9600/11/17040).
The fitting of this set has been deferred till next financial year (G. 14768/11/22397).
It has now been approved to fit short-distance sets in all battleships and cruisers of the first and
second divisions of the Home Fleet. There will, for the present, be no increase of complement of
telegraphist ratings te work these sets (G. 0567/11/22470).
In view of this decision the fitting out specifications for short distance vets have been
completely re-written and revised; and the alterations to establishment includes a hand
operating key, Pattern 2483, and a box-screening (with detectors and protecting switch), of the
Type “‘ C” pattern, instead of the operating switch Mark I*. and the Type “B” box-screening,
and its fittings.
Policy—It. has been decided that, of the ships to be fitted with short distance sets, all the
battleships shall have the existing 5-mile set, but that the cruisers shall wait till a set with a
longer range is available. 1% is proposed that then all the battleships shali have the new set.
LExperiments.—The experiments mentioned in last year’s Annual Report to be conducted with
a set to send out a 30,000-foot wave were temporarily discontinued, but are now again in progress,
It is thought, however, that possibly the short wave with quenched spark, utilising higher
power, will be more suitable for this set.
PORTABLE HARBOUR AND DEFENCE SETS.
These sets are now completed as to design, and are only waiting for delivery of gear. At
the same time many of the instruments have been modified as to details where experience has
shown this to be necessary.
B4
16
Power Generators—Referring to page 59 of W.T. Appendix to Annual Report 1910, the engine
————
as designed for paraffin has been modified in detail and made suitable for petrol. The engine has
two cylinders, which are horizontally opposed, and it runs with very little vibration. It is air
cooled, the fly wheel spokes being so shaped that a strong draught is directed by them on to the
cylinders. Ignition is by high tension magneto. The carburettor is an Amac carburettor. The
first lot of 20 engines have been delivered from the contractors, and are, on the whole,
satisfactory, with the exception that they throw a certain amount of oil. It is thought that a few
small alterations in design will overcome this defect in future engines.
A very good engine was obtained from the Marconi Company for trial against the Service
engine. It is much lighter and cleaner, but it has not got the same reserve of power.
It has been found impracticable to fit a governor, which will work satisfactorily and will not
hunt, to so small an engine. It is recommended, therefore, that the governor as fitted to the Service
engine should be disconnected, and the engine speed controlled by means of the throttle and air
levers. New engines will have no governor, and the speed will be controlled by the spark,
Alternators.— Very considerable delay has been experienced with these machines owing to the
firm Messrs. Veritys, who were given the order, failing to comply with the requirements of the
specification. However, Messrs. Crompton have produced a very satisfactory machine, and
the order placed with Veritys has therefore been cancelled. It is hoped that these machines
will be ready for delivery by about March or April 1912. This machine can be clearly seen on
the cart in Plate 1V.
Mains.—A. four-core cable will be supplied for conveying the power from the alternator to
the transmitting instruments. Two of the cores will be used for power, one for a buzzer for
signalling between the operator at the instruments and the operator at the engine, and one for the
earth wire for screening. This must be earthed at both ends to the metal frames of the instruments,
see page 21 of W.T. Appendix to Annual Report, 1910.
Curts.—T wo carts have been made locally under the supervision of “ Vernon,” and have been
well tested. Various party have given way, and this has caused some delay in repairs and replace-
ments, &c. The carts have now, however, been so reconstructed that they appear quite satisfactory,
and it is proposed to get firms to quote for carts exactly to these two as patterns. The two carts
loaded up with all gear on them are shown in Plates II]. and IV.
Mast.—The mast described in the Annual Report 1909, has proved quite satisfactory, but it is,on
occasion, somewhat difficult to erect. If the ground on which it is to be set up is not quite level,
or if it is not clear of bushes and similar obstructions, the adjustment of the stays is not at all easy ;
and if it is blowing at all hard under these conditions the process of getting the mast up becomes a
rather critical operation, as the tubes are liable to buckle.
It is, therefore, proposed to experiment with wood-lengths to be used in the place of the steel
tubes, and two sets of such lengths are now on order. Canadian spruce and bamboo will be tried,
If these do not prove more satisfactory it is proposed to divide the mast up into two short. masts
of only 30 feet in height, as in the Marconi set described below. This reduction in height and
consequent rearrangement of aerial will have the effect of emphasising the directional effect and
of (in all probability) reducing the range. These points, however, would have to be confirmed by
experiment, and the pros and cons weighed before deciding which type of mast would be the more
suitable all round.