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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