Outer foil orientation

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Analog Assassin
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Outer foil orientation

Post by Analog Assassin »

Assuming you can find, or if your caps have the outer foil orientation marked, where do you connect the outer foil to? On a Marshall plexi-style amp, for example, on the tone stack, would the outer foil lead to ground? Cathode bypass cap, outer foil to ground? Coupling caps?
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martin manning
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Re: Outer foil orientation

Post by martin manning »

Connect it to the node with the lowest impedance to ground. Usually that will be "up-stream" in the signal flow, unless the cap itself is connected to ground at one end.
Cliff Schecht
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Re: Outer foil orientation

Post by Cliff Schecht »

In general you connect it to the lowest impedance point between the two terminals. For gain stages this means pointing the outer foil at the node between the plate/plate resistor and the non-foil side towards the next stages input. For filters and such this means pointing the foil towards ground.
Cliff Schecht - Circuit P.I.
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