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Most of the modern radio-transmitters can communicate both telegraph and telephone signals.
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You might ask why engineers have generally chosen to supply us with a.c. rather than d.c. for our household needs.
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We know the primary coil in the transformer to have more turns than the secondary one.
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The zinc in the dry cell accumulates a great many excess electrons which will move to the carbon electrode.
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Fig. 10 gives a drawing of a valve; the filament will be seen in the centre.
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This question was discussed at the conference.
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We have learned to manufacture dozens of construction materials to substitute iron.
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