COIL, INDUCTION


 
Coil Induction No. 1

Two windings of 1 Ohm (silk covered copper wire of 25 mils) and 25 Ohms (11 mils).  The cores are a 9/32 inch bundle, No. 24 S.W.G. well annealed, charcoal iron, left black from the annealing process to prevent eddy currents.

Used on local battery circuits.
 

 
Coil Induction No. 2

Two windings of 1 Ohm (silk covered copper wire of 25 mils) and 150 Ohms (7 mils).  The cores are a 9/32 inch bundle, No. 24 S.W.G. well annealed, charcoal iron, left black from the annealing process to prevent eddy currents.

Used on switchboards on local battery circuits.
 

Coil Induction No. 3

Two windings of 1.7 Ohms and 75 Ohms.

Coil Induction No. 4

Two windings of 17 Ohms and 26 Ohms.

Coil Induction No. 6

Used on Operators C.B. systems.

Coil
Primary - 11 ohms
1st Secondary - 58 ohms
2nd Secondary - 240 ohms

Dimensions of base are 7.1 in x 2 in.
 

 
Coil Induction No. 7

Two windings of 17 Ohms and 26 Ohms.

Used on Supervisors Circuits.
 

Coil Induction No. 8

Four windings of 18 Ohms and 130 Ohms / 18 Ohms and 490 Ohms.

Used on CB Switchboards.

Coil Induction No. 9

Two windings of 17 Ohms and 26 Ohms.

Used on Supervisors Circuits.

Coil Induction No. 10

Two windings of 1.7 Ohms and 75 Ohms.

Used on Telephone No. 44.


Coil Induction No. 12

Two windings of 25 Ohms (tags 3 & 4) and 1 Ohm (tags 1 & 2).

Standard for L.B. system telephone and switchboards.
 

Coil Induction No. 13
 
Coil Induction No. 14

Two windings of 26 Ohms (1400 turns) (tags 3 & 4) and 17 Ohms (1700 turns) (tags 1 & 2).


 
Coil Induction No. 15

Three windings of 38 ohms (tags 5 &6), 19 Ohms (tags 3 & 4) and 1 Ohm (tags 1 & 2).

Used in the Bellset No. 23
 


 
Coil Induction No. 18

Two windings of 17 Ohms (1700 turns) (tags 1 & 2) and 33 Ohms (1400 turns) (tags 3 & 4).

Used with Anti-sidetone Transformer No. 35A.


 
Coil Induction No. 20

Three windings of 30 Ohms (1600 turns) (tags 4 & 5), 200 Ohms (1580 turns) (tags 3 & 5) and 44 Ohms (2400 turns) (tags 1 & 2).

Also two non inductive resistances of 30 Ohms (tags 3 & 6) and 85 Ohms (tags 2 & 5).

Coil Induction No. 21

Three windings of 1 Ohm (400 turns) (tags 1 & 2), 17 Ohms (1000 turns) (tags 3 & 4) and 33 Ohms (1500 turns) (tags 5 & 6).

In Australia some 300 series magneto phones used the 21A as follows (no winding details);
1 Ohm between tags 1 & 2 .
17 Ohms between tags 3 & 4.
33 Ohms + 900 Ohms NI between tags 5 & 6
tags 3 & 5 linked.
.


 
Coil Induction No. 22 Mark 2

Three windings of 50 Ohms (1600 turns) (tags 3 & 4), 415 Ohms (2000 turns) (tag 3 & joined to 150 Ohm NI resistance) and 17 Ohms (2000 turns) (1 & 2).

Also has three non-inductive resistances of 150 Ohms (tag 5 and 415 Ohm coil), 50 Ohms (tags 5 & 6) and 150 Ohms (tags 3 & 7).

Coil Induction No. 24

Three windings of 83 Ohms (1600 turns) (tags 3 & 4), 550 Ohms (2000  turns) (tags 3 & 5) and 21 Ohms (2000 turns) (tags 1 & 2).

Also has two non inductive resistances of 50 Ohms (tags 5 & 6) and 150 Ohms (tags 3 and 7).

Coil Induction No. 25

Two windings of 25 Ohms (tags 3 & 4) and 1 Ohm (tags 1 & 2).

Coil Induction No. 27

Five windings of 35 Ohms (2600 turns) (tags 1 & 2), 75 Ohms (1800 turns) (tags 3 & 4), 30 Ohms (800 turns) (tags 3 & 5).

Also has two non-inductive resistances of 30 Ohms (tags 5 & 6) and 30 Ohms (tags 3 & 7).


 
Coil Induction No. 30

Three windings of 15 Ohms (1220 turns), 10.5 Ohms (666 turns) and 7.5 Ohms (420 turns).

Used on the Telephone No. 700.

 

Coil Induction No. 31

Three windings of 6 Ohms (315 turns) (tags 2 & 3), 8 Ohms (540 turns) (tags 1 & 2) and 22 Ohms (900 turns) (tags 4 & 5).

Coil Induction No. 32

Three windings of 7 Ohms (235 turns) (tags 2 & 3, 11 Ohms (402 turns) (tags 1 & 2) and 23 Ohms (670 turns) (tags 4 & 5).

 
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Last revised: July 19, 2016

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