No's N1641 - N1645 & N1650 - N1655

Intercommunication Table and Wall Telephones
Radial Selector, Single Line Local Battery, Secret System

N1641 shown

n1641.jpg (22139 bytes)

A secret system is sometimes preferred, and this range of instruments has been specially designed to give secrecy and be entirely free from "cross talk," electrostatic and magnetic induction's.

The case work is of high-class finished hardwood.

The micro-telephone is fitted with an electromagnetic receiver, "inset" transmitter and all-metal hygienic mouthpiece.

The radial selector is of substantial design, positive in action, and does not require either automatic or manual replacement, as a ring can be received with the pointer in any position.

Cards giving full working instructions and having spaces for inserting the names of stations, are supplied. Also a diagram showing how the instruments, cables and batteries are connected up.

Three cells are required at each station up to 500 feet of cable between the two most distant stations, and four cells for over 500 feet of cable.n1643.jpg (7877 bytes)

No. of Lines   Code No.   Weight lbs.
5   N1640   6.5
10   N1641   6.5
15   N1642   6.5
20   N1643   6.5
25   N1644   6.5
30   N1645   6.5

Overall dimensions 12 x 10 x 6 inches.

When these instruments are required as wall sets a bracket is supplied.

N1643 shown right

Intercommunication Table and Wall Telephones
Radial Selector, Single Line, Central Battery

These instruments are of exactly the same design and outward appearance as N1640 - N1645 those above, but although secrecy is not given, the circuit and working parts are so arranged that the mischievous listening-in by simply moving the selector arm over the numbers has been guarded against.

Full working instructions are provided, also a diagram showing the necessary connections for installation.

The central battery should be located as near the centre of the system as possible.

No. of lines   Code No.   Weight lbs.
5   N1650   6.5
10   N1651   6.5
15   N1652   6.5
20   N1653   6.5
25   N1654   6.5
30   N1655   6.5

Overall dimensions 12.5 x 10.25 x 6 inches.

NOTE - When these instruments are required as wall sets a bracket is supplied.

The radial selector, secret system and central battery system instruments are made as table sets only.

This arrangement saves customers the necessity of keeping two distinct types in stock.

When these instruments are required to be fixed and used as wall sets we supply a bracket as illustrated.

The shelf is of the same high-class finish hardwood as the instruments. and the supports are black enamelled iron.
Code No. N8530

Battery Boxes
To hold 3 wet or dry cells. Code No. N3230
To hold 4 wet or dry cells. Code No. N3231

Junction Boxes

Code No. No. of terminals For Instruments Dimensions ins Weight lbs.
N3300   10   N1601, N1611, N1640 and N1650   7.25 x 6 x 2   1.9
N3301   16   N1600, N1603, N1610, N1613, N1641, N1642 and N1651   10.25 x 6 x 2   2.75
N3302   22   N1604, N1605, N1614, N1615, N1643, N1652, N1680 and N1682   13.25 x 6 x 2   4
N3303   28   N1602, N1606, N1607, N1612, N1616, N1617, N1644, N1653 and N1654    16.25 x 6 x 2   5
N3304   34   N1608, N1608, N1618, N1618, N1645, N1655, N1681 and N1683   19.25l x 6 x 2 5.75

Cables for Single Line Sets

Braided   Lead covered
Code No.   Code No.   No. of conductor pairs   For instruments
N3350   N3370   7   N1640
N3351   N3371   10   N1601, N1611, N1650
N3352   N3372   14   N1603, N1613, N1641, N1651
N3353   N3373   19   N1642, N1652
N3354   N3374   24   N1605, N1615, N1643, N1653
N3355   N3375   29   N1607, N16I7, N1644, N1654
N3356   N3376   34   N1608, N1618, N1645,N1655

Cables for Metallic Line Sets

Braided   Lead covered
Code No.   Code No.   No. of conductor pairs   For instruments
N3360   N3380   9   N1600, N1610
N3361   N3381   13   N1602, N1612, N1680
N3362   N3382   16   N1681
N3363   N3383   21   N1604, N16I4, N1682
N3364   N3384   27   N1606, N1616
N3365   N3385   33   N1608, N1618, N1683

The use of lead-covered cable is strongly recommended for intercommunication telephone installations.

Taken from the Ericsson catalogue, edition 26

Also see Multiphone system

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Last revised: April 09, 2000