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Purpose of these Caps?

The partial Fisher 50-AZ schematic below shows an interesting feature in the power amp circuit. Fisher used a transformer between the push-pull driver cathodes and the power amp grids. According to Bruce Rozenblit, the transformer is 1:1. It appears that the transformer is being used like any other IT; to isolate the positive DC voltage at the driver - usually at the anodes, but in this case, cathodes - from the negative bias at the grids. What I'm not sure of is the purpose for C10 and C11. I think they're intended to impose a load on the secondary, rather allowing it to operate into an open circuit. Perhaps the transformer "misbehaves" when the secondary is operated with no load. Anyone have any other ideas regarding the purpose of these parts, or maybe practical experience with this arrangement?










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Topic - Purpose of these Caps? - Triode_Kingdom 23:42:32 08/27/16 (22)

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