CO129-547-1 Wireless telegraph and telephone services 16-1-1934 - 26-1-1934 — Page 18

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Memorandum for despatch to Crown Agents

with Indents.

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I suggest that the following covering letter be

sent with our Indents for Radio Telephony apparatus :-

"In connection with the attached Indents for wireless

telephony apparatus it will be noticed that, as in the case

of the Telegraphy Indents, some variations from the

contractors' original specifications have been made.

(1)

Filament Supplies For Telephony.

To enable the use in case of emergency, of the two

Type SWB4b Telegraphy Transmitters already ordered, for

Telephony, the possibility of A.C. Filaments on the Telephony

Transmitter is suggested. The modulator panel could remain

with D.C. Filaments, and would then be available for use on

either of the three SWB4b Transmitters. In the event of

the contractors still stipulating D.C. Filaments on the

SWB4b for Telephony, their views on the possibility of using

the other transmitters on Telephony in case of necessity,

would be appreciated. It is realised of course that the

SWB4b for Telephony will normally be provided with D.C.

Filament Resistance units instead of the Transformers and

chokes of the Telegraph Model.

In this connection we presume that there is no

objection to a 3 phase Motor for the D.C. Filament Motor

Generator, and have altered the Indent accordingly. The

M.W.T. Co's specification showed a D.C. Motor.

(2)

Power Induction Regulator.

This is included as in the case of Telegraph

Transmitters.

The transmitter will probably be used for

Telegraphy at times.

(3)

Main Power Transformer.

M.W.T Co's specifications assumed a 500 cycle single