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Thread: Sunn Beta Lead Blown Resistor

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    Sunn Beta Lead Blown Resistor

    My Beta Lead fried the resistor between the speaker output and master preamp output. It's on the ground of both jacks and I'm not even sure why its there or why it would spontaniously combust. I can't find what type of resistor it is on the schematics, hoping someone can shed some light on the subject.

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    Supporting Member loudthud's Avatar
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    The resistor is 10 ohms 5% 1/2W carbon film. I'm not finding it on any of the schematics I have.

    The speaker jacks are insulated from the chassis, the ground return for the speaker jacks goes via a black wire to the power amp PCB. The effects loop jacks are conneccted to the chassis at the back panel and the resistor is connected between one of the effects loop jacks and the ground side of the speaker jacks.

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    Member gearhead63's Avatar
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    I know this is an old post, but just so you know, that resistor is a dissipation limiting overload resistor. Keeps from frying the op transistors if there is an overload or short circuit in the out put to speaker circuit.

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