| 摘要 |
1515736 Television intercarrier sound separators PHILIPS ELECTRONIC & ASSOCIATED INDUSTRIES Ltd 21 Oct 1975 [16 Aug 1975] 43141/75 Heading H3Q In an intercarrier sound separator for a television receiver in which the sound 1 f signal is obtained by coupling to a sound trap in the video signal path, further means are coupled to the sound trap to restore losses of attenuation due to the first coupling. In one embodiment, the sound output impedance is coupled to the sound trap 4, 5 by a transformer 8, 10 in the capacitative branch of the sound trap. The attenuation compensation is provided by a resistor 6 connected between a centre tap on inductor 4 and a common point e.g. earth. In a modification Fig. 2 (not shown) capacitor 5 is replaced by two series capacitors and the resistor is connected to the common point of the capacitors. In a further modification, Fig. 3 (not shown) the resistor is replaced by an inductor and the coupling to the tuned circuit 8, 9, is capacitative.
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