ERICSSON SWITCHBOARD No's 660 - 666


STANDARD SWITCHBOARD FOR 20 to 160 METALLIC-CIRCUIT SUBSCRIBERS' LINES

No. 664 shown

664.jpg (38031 bytes)Fitted with jack and indicator for each line. For connecting the lines to each other pairs of plugs and cords are provided, and a three-position combined ringing and speaking key in connection with each pair. When the lever of this key is polled towards the operator (in which position it will remain until released), the latter is in the circuit and can speak to the subscriber; when the lever is pressed away from the operator (it only remains in this position while held there), generator current goes out on the calling cord, the right-hand one of each pair. In the normal position of the key the two lines are through to each other, and the operator is entirely out of the circuit.  Two keys T are provided for listening on either one of two lines independently of the other, two keys 1 do the same for ringing, and two keys B are provided for ringing with battery instead of alternating current. These six keys can only be used with the combined key in the forward or listening position.

A hand-generator is provided, but this can be put out of circuit by means of a key M, if it is found more convenient to use a machine-driven generator. This is to be recommended for all switchboards of fifty lines and upwards, where the calls are anything like frequent.

A hand micro-telephone is provided for operating, and terminals for generator (Genr.), ringing battery (R B), earth (E), operator's speaking battery (M B), and extension bell (E B).

Facilities are also provided for making a rough test of the lines.
752 and 666 are for two operators' positions.

Catalogue Number   660   661   662   663   664   665   752   666
Number of lines   20   25   30   40   50   100   100   160
Pairs of Cords and Plugs   5   5   6   8   10   12   12   20
Height in Inches   59   62   63   63   64   64   65   66
Width in Inches   17.2   17.2   19   20   22   37   37   37
Weight in lbs.   120   124   126   145   154   188   229   242
PRICE   22 5 0   25 0 0   28 0 0   36 0 0   44 0 0   74 0 0   82 10 0   114 0 0


Taken from the Ericsson Telephone Catalogue 1903

Home page BT/GPO Telephones Ericsson Telephones Ericsson Home Page Ericsson PABX All Telephone Systems

Last revised: April 18, 2000