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Speaker circuit for the 38-7
EdHolland
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#4

01-29-2018, 12:02 AM
morz is correct, the big coil is the field coil.

The full +350V comes in and supplies the OP transformer for the 6F6. It is also connected to the field coil, and the other end of the coil feeds subsequent circuitry in the radio. This achieves 2 things rather efficiently.

1) The current to the rest of the radio is used to create the magnetism needed for the speaker.

2) The supply passing through the field coil's large inductance is extra filtered, providing a quiet B+ supply for the sensitive stages of the radio.
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Messages In This Thread
Speaker circuit for the 38-7 - by cpollock - 01-28-2018, 10:35 PM
RE: Speaker circuit for the 38-7 - by morzh - 01-28-2018, 11:34 PM
RE: Speaker circuit for the 38-7 - by cpollock - 01-28-2018, 11:38 PM
RE: Speaker circuit for the 38-7 - by EdHolland - 01-29-2018, 12:02 AM
RE: Speaker circuit for the 38-7 - by morzh - 01-29-2018, 10:41 AM
RE: Speaker circuit for the 38-7 - by cpollock - 01-29-2018, 10:58 AM



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