SECTION
D.
AKTIEBOLAGET
L. M. ERICSSON & Co:
STOCKHOLM.
Works :
NRIS. 5, 15, 17 & 19,
TULEGATAN, STOCKHOLM.
GR. SAMPSONIEWSKY PROSP. NR. 70, ST. PETERSBURG.
Offices:
NR. 5, TULEGATAN, STOCKHOLM.
GR. SAMPSONIEWSKY PROSP. NR. 70, ST. PETERSBURG.
154/6, TEMPLE CHAMBERS, TEMPLE AVENUE, LONDON, E.C.
Telegraphic Addresses
MIKROFON, STOCKHOLM. -!- ERICSONMIKROFON, ST. PETERSBURG. -!- ERICSSON, LONDON.
1
AKTIEBOLAGET L. M. ERICSSON & C0.
STOCKHOLM.
2
AKTIEBOLAGET L. M. ERICSSON & CO.
Inter-Communication Telephone
Instruments
In order to make it possible to communicate between different parts of
big establishments, such as warehouses, factories, or offices, without the aid
of a Telephone Exchange, inter-communication instruments have for a long time
been in use. These instruments have been of various patterns, but it is common
to all of them that one instrument can, by means of a simple manipulation, he
brought into communication with any other instrument on the same system.
We have for some time been making
instruments of this description, but, as the demand lately has largely
increased, we have found it necessary to construct a new system, which we claim
is a decided improvement on the old ones, and which we are sure will give every
satisfaction.
The instruments are manufactured for
systems with 10, 15, 20, 30, 40, 50, or 60 lines, and they can be
properly divided into two groups, viz., instruments for 10, 15 and 20 lines,
and instruments for 30 lines and upwards.
The first-mentioned pattern instrument
is partly made with the switch and the telephone instrument combined, and
partly with the switch fitted separately. In either case the switching is done
by turning the hand of the switch to the required number. When the instrument
is not in use, the switch should be left in its resting position, which is
marked A.
The latter pattern is made with the
switch separate from the telephone instrument. The switch is fitted with one
spring jack for each line, and also with one jack, A (resting position),
and a plug and cord for switching. A connection is effected by placing the plug
in the jack of the wanted line. When not in use the plug should be inserted in
the jack marked A.
A most important improvement is that
the numbers on the switch are placed consecutively, so that all instruments are
exactly alike. There are several other improvements in the construction ; in
particular, if the switch or plug, as the case may be, be not replaced to the
resting position, A, the bell of the instrument will still ring when a
signal is given by any of the other instruments. It is, however, not possible
to answer a call until the hand of the switch or the plug i s in the
position A.
Another point is, that if either of the
two persons conversing omits to replace his switch or plug to A and a
third person calls, only the bell of the called instrument will ring, the other
one being cut out.
With regard to the lines, the
inter-communication instruments can be divided into two distinct groups, viz.,
instruments working on single lines and a common return, and instruments
working on metallic circuits. In installations with 20 or more stations, or
when the lines are of a considerable length, we strongly recommend the use of
metallic circuits. When several conversations are going on simultaneously on a
single-line system, the overhearing, by reason of induction between the lines,
is rather bad. This drawback is perfectly overcome by the use of metallic
circuits. The price of the metallic-circuit instruments is only slightly higher
than for the single-line ones. The cable used for metallic-line instruments
consists of twice as many wires as are required for single-line instruments.
The increase in price, however, is not great.
STOCKHOLM.
3
AKTIEBOLAGET L. M. ERICSSON & CO.
On page 28 we give for comparison of cost the prices of
two installations, one for to single and the other for 10 metallic lines.
Instruments for more than 20 lines are only made for metallic circuits, but
they can, of course, also be used on single lines. If required, single-line
instruments are made to special order.
Inter-communication
instruments are made both for battery and magneto ringing.
The chief advantage of the battery-ringing instruments is
the convenience of only having to press the button when giving a signal. On the
other hand, there are several disadvantages, one of which is that the ringing
battery must now and then be renewed, and that the signal is uncertain if the
insulation of the installation of the cable has been damaged through damp or
any other cause. For these reasons the magneto-ringing instruments have lately
been more and more used, and we particularly call attention to the advantage,
not to say necessity, of using this system for large installations with long
lines.
Should an installation be required for less than 10 lines,
or for a number not found in our Catalogue, the instrument for the nearest
higher number of lines should be used, and the excess numbers left blank. In
most cases it is advisable to have a few spare numbers, as the original cost -is
only slightly increased. The change of the whole system would, however, involve
a heavy expense, if all instruments have to be taken down and replaced with
others for a greater number of lines.
These
instruments are divided into the following groups, viz.:
(1) Battery-ringing
inter-communication telephone instruments for to, 15, or 20 single lines.
(2)
Battery-ringing
inter-communication telephone instruments for to,
15, or 20
metallic lines.
(3) Inter-communication switches for
to, 15, and 20 metallic lines, to be used in con-
nection with magneto ringing-
telephone instruments.
(4) Inter-communication plug switches for 30, 40, 50, or
6o metallic lines, lo be used in connection with magneto or battery riming
telephone instruments.
STOCKHOLM.
4
AKTIEBOLAGET L. M. ERICSSON & CO.
DIRECTIONS FOR USE.
The Originating
Subscriber.
(1) Place
the hand of the switch on the required number.
(2) Press
the ringing key, S.
(3) Remove
the hand micro-telephone from the hook, put the receiver to the ear, and wait
for a reply.
(4) Restore
the switch to its normal position, with the hand pointing on A.
The
Called Subscriber.
(1) When
the bell rings replace the switch to A, if this is not already done.
(2) Take
the hand micro-telephone from the hook and reply.
During
conversation the key in the hand micro-telephone should always be pressed down.
If the persons conversing should find that the induction
from other lines is troublesome. they can, to a. considerable extent, remedy
this by the called subscriber placing the hand of his switch on the number of
the originating subscriber, and by both keeping the keys, T, pressed
down as long as the conversation lasts.
STOCKHOLM.
5
AKTIEBOLAGET L. M. ERICSSON & CO.
GROUP I.
Battery=Ringing
Inter= Communication Telephone Instruments, for Installations with 10, 15, or
20 Single Lines . . . . .
These
instruments include both the switching arrangements and the telephone
instrument. The switch is provided with a handle, to be placed on the required
number, a galvanic bell, a press button, S (on the left-hand side of the
instrument), for the ringing, and a press button, T (on the right-hand
side of the instrument), by means of which two instruments engaged in a
conversation can be connected with each other by two separate wires, instead of
using the common return wire. There is also fitted a hand micro-telephone, with
a key in the handle, and one induction coil.
STOCKHOLM.
6
AKTIEBOLAGET L. M. ERICSSON & CO.
Fig. 1.
WALL TELEPHONE, No. 760.
Battery-Ringing Inter-Communication
Wall Telephones for
Single Lines. (Fig. 1.)
|
Catalogue
Number … |
760 |
761 |
762 |
|
Code Word … … … … … … |
Morchioso |
Morcillas |
Mordicus |
|
Number of Lines … … … … |
10 |
15 |
20 |
|
Height in Inches … … … … |
15 |
15 |
15 |
|
Width in Inches … … … … |
6.5 |
6.5 |
6.5 |
|
Weight in Lbs … … … … … |
4 |
4 |
4.2 |
|
Price
… |
£2
13 0 |
£2
15 0 |
£2
18 6 |
CABLES, Nos. 4001, 4002, 4003, and 4004,
page 22.
BATTERY BOXES and CELLS, pages 23
and 24. JUNCTION BOXES, Nos. 790,
791, and 792, page 2I. SPARE PARTS, pages 25,
26, and 27.
STOCKHOLM.
7
AKTIEBOLAGET L. M. ERICSSON & C0.
Fig.
2.
TABLE TELEPHONE, No. 765.
Battery-Ringing Inter-Communication
Table Telephones for
Single Lines. (Fig. 2.)
|
Catalogue
No … |
765 |
766 |
767 |
|
Code Word … … … … … … |
Mordebain |
Mordiscare |
Morditrice |
|
Number of Lines … … … … |
10 |
15 |
20 |
|
Height in Inches … … … … |
9 |
9 |
9 |
|
Width in Inches … … … … |
11 |
11 |
11 |
|
Weight in Lbs … … … … … |
4.9 |
5.1 |
5.1 |
|
Price
… |
£2
18 6 |
£3
2 0 |
£3
7 6 |
CABLES,
Nos.
4001,
4002, 4003, and 4004, page 22. BATTERY
BOXES and CELLS, pages 23 and 24. JUNCTION BOXES, Nos. 790,
791, and 792, page 21. SPARE PARTS,
pages 25, 26, and 27.
The fitting up of
these instruments can be done in two different ways, viz.:
Diagram No. I (page 30) shows the fitting with a microphone battery of two Leclanche cells for each instrument. The carbon pole is connected to the terminal marked M, and the zinc pole to terminal Z. These cells serve also as ringing batteries, but may be strengthened by a third cell, the carbon pole of which is to be brought to terminal S, and the zinc pole to the carbon pole of the microphone battery.
Diagram No. 2 (page 31) shows the
second manner of fitting the instruments. The microphone batteries consist, as
before, of two Leclanche cells for each instrument, and they are connected to
terminals M and Z, as already described. For the signals a common
ringing battery of three or four cells is used, which ought to be fitted in a
central position. The zinc pole is connected with the common return wire marked
E, and the carbon pole to a special wire marked S. From this wire
connections are brought down to the terminals S on the different
instruments.
In both cases the lines are connected
to the terminals bearing their respective numbers, but it must be borne in mind
that the terminal with the same number as a certain instrument is on that set
left vacant, and the wire instead brought to terminal A. Instrument No.
7 will thus, for example, have its on line wire connected to A, so that
No. 7 terminal is left blank. The terminals E on all the instruments
should be connected to the common return wire.
STOCKHOLM.
8
AKTIEBOLAGET L. M. ERICSSON & CO.
GROUP
2.
Battery=Ringing Inter= Communication Telephone
Instruments, for 10, 15, and 20 Metallic Lines. .
These instruments are very similar to those for single lines, just
described, and thus include both the switch and the telephone instrument. The
press button T is, however, excluded, because the instruments are
constructed for metallic lines.
STOCKHOLM.
9
AKTIEBOLAGET L. M. ERICSSON & CO.
Fig.
3.
WALL TELEPHONE, No. 768.
Battery-Ringing Inter-Communication
Wall Telephones for
Metallic Lines. (Fig. 3.)
|
Catalogue
Number … |
768 |
769 |
770 |
|
Code Word … … … … … … |
Morenula |
Moretum |
Morfondre |
|
Number of Lines … … … … |
10 |
15 |
20 |
|
Height in Inches … … … … |
16 |
16 |
16 |
|
Width in Inches … … … … |
6.5 |
6.5 |
6.5 |
|
Weight in Lbs … … … … … |
4 |
4.2 |
4.6 |
|
Price
… |
£2
16 0 |
£3
0 0 |
£3
3 0 |
CABLES, Nos. "4051, 4052,
4053, and 4054, page 22. BATTERY BOXES
and CELLS, pages 23 and 24.
JUNCTION
BoxEs,
Nos.
793,
794, and 795, page 21. SPARE PARTS,
pages 25, 26, and 27.
STOCKHOLM.
10
AKTIEBOLAGET L. M. ERICSSON & CO.
Fig.
4.
TABLE
TELEPHONE, No. 771.
Battery-Ringing Inter-Communication
Table Telephones for
Metallic Lines. (Fig. 4.)
|
Catalogue
Number … |
771 |
772 |
773 |
|
Code Word … … … … … … |
Morigerate |
Moriuntur |
Mornamos |
|
Number of Lines … … … … |
10 |
15 |
20 |
|
Height in Inches … … … … |
9 |
9 |
9 |
|
Width in Inches … … … … |
11 |
11 |
11 |
|
Weight in Lbs … … … … … |
4.9 |
5.1 |
5.3 |
|
Price
… |
£3
3 6 |
£3
8 0 |
£3
14 0 |
CABLES, Nos. 4051,
4052, 4053, and 4054, page 22. BATTERY
BOXES and CEILS, pages 23 and 24. JUNCTION BOXES, Nos. 793,
794, and 795, page 21.
SPARE PARTS, pages 25, 26, and 27.
The fitting up of
these instruments can be done in two different ways, viz. :-
Diagram No. 3 (page 32) shows the fitting with a microphone battery of two cells for each instrument. The carbon pole is connected to terminal M, and the zinc pole to terminal Z. The same batteries are also used for ringing purposes, but a third cell call be added, if necessary. The carbon pole of the third cell should be brought to terminal S, and the zinc pole to the carbon pole of the microphone battery.
Diagram No. 4 (page 33) shows the other way of fitting the instruments. The microphone batteries are arranged exactly as before described, but a common ringing battery is used. This battery consists of three or four cells, which are connected to the wires S and C in the cable. The terminals S and C fitted on the instruments are connected to the above-mentioned wires.
The lines are connected in exactly the same way as
described under Group 1, only that there are two terminals marked A.
These instruments
can also, if required, be used for single lines.
STOCKHOLM.
11
AKTIEBOLAGET L. M. ERICSSON & CO.
GROUP 3.
Inter= Communication
Switches, or 10, 15, and 20 Metallic Lines, to be used in connection with
Magneto=Dinging Telephone Instruments. . . .
These instruments include the switching
arrangements only, and are to be used in connection with magneto-ringing
telephone instruments. They are only made for metallic circuits. The switches
are provided with a hand, which, in the resting position, should point to A,
and the switching is done by turning it on to the required number.
The
manipulation of the instruments is exactly the same as already described under
Group 2, except that the calling is done from the attached telephone
instrument.
STOCKHOLM.
12
AKTIEBOLAGET L. M. ERICSSON & CO.
Fig.
5.
INTER-COMMUNICATION SWITCH, No. 776.
Inter-Communication
Switches for 10, 15, and 20 Metallic
Lines, to be used in connection with Magneto-Ringing
Telephone Instruments. (Fig. 5.)
|
Catalogue
Number … |
774 |
775 |
776 |
|
Code Word … … … … … … |
Morniado |
Moroncho |
Morositas |
|
Number of Lines … … … … |
10 |
15 |
20 |
|
Height in Inches … … … … |
12 |
12 |
12 |
|
Width in Inches … … … … |
6.5 |
6.5 |
6.5 |
|
Weight in Lbs … … … … … |
2 |
2.2 |
2.2 |
|
Price
… |
£1
8 0 |
£1
12 0 |
£1
15 6 |
CABLES, Nos. 4051,
4052, 4053, and 4054, page 22.
BATTERY BOXES and CELLS, pages 23 and 24. JUNCTION BOXES, Nos. 793,
794, and 795, page 21. SPARE PARTS,
pages 25, 26, and 27.
STOCKHOLM.
13
AKTIEBOLAGET L. M. ERICSSON & CO.
The following Magneto-Ringing Telephone
Instruments are suitable for use in connection with Switches Nos. 774,
775, and 776.
Fig. 6.
