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Handling Hi-Fi Service

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cases except to try, as a last resort, physically relocating the ground points of the input slages.

There nre few problems peculiar to !he remainder of the amplifier cir-cuilry that are not encountered in p a. or radio repair work. If ihc customer complains ihat he seems to run through ouiput tubes on a Hf ty- or sixly-watt amplifier (these higher-po\ver units almost always use ftxed bias) every four or five months. ii is a good idea to check the bias setting in his home and under both day and evening a.c. linę conditions. In residen-