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Patent classifications
H
ELECTRICITY
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H04
ELECTRIC COMMUNICATION TECHNIQUE
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H04M
TELEPHONIC COMMUNICATION
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1/00
Substation equipment, e.g. for use by subscribers
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H04M1/64
Automatic arrangements for answering calls; Automatic arrangements for recording messages for absent subscribers; Arrangements for recording conversations
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H04M1/65
Recording arrangements; for recording a message from the calling party
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