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#1 |
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In recent years the MSD trigger polarity has received some attention. In the "olden days," it was never considered.
For this question, we are talking about an analog MSD 6AL control. I do understand that for the analog controller, the most retarded timing is the correct polarity. Since the subject began getting attention I have checked a number of 6AL and 7AL analog controllers and so far, each had the correct polarity when the wires connected "color to color" [green to green, purple to purple] When the colors are swapped, [green to purple] the timing advances about 5 degrees. Now the question; Why does the wrong polarity advance the timing? It is as if the controller is predicting the future ![]() Does the control box, when polarity is correct, have that much signal delay? [about 5 degrees] Anyone know the truth?
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Larry Woodfin 471W |
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#2 |
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Larry sent u an email. Dick
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#3 |
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the signal is either triggered at the leading edge of the wheel magnet [incorrect polarity] or the trailing edge of the wheel magnet, [correct polarity] thus, the difference in timing.
The analog controller is designed to process the trailing edge signal.
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Larry Woodfin 471W |
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#4 |
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Larry, Do you have a scope?
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Adger Smith (Former SS) |
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