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Fox's Mercantile

On 2/17/19 2:11 AM, wrote:
It does seem kind of bizarre that the (+) terminal is used for the high
voltage return, (knowing that spark plugs complete the circuit by being
connected to the engine block, which is connected to the battery
GROUND).

The internal resistance of a car battery is close to zero ohms.
When the points open, the magnetic field from the primary collapses.
This causes a huge inductive kick voltage spike. The condenser across
the points acts like a tuned circuit to sustain the high voltage by
acting like a tuned circuit. The secondary being in series with the
primary acts like a auto-transformer and increases the high voltage
oscillations to a value high enough to create a solid, hot, spark
across the electrode of the spark plug.

The fact that the return is via the positive terminal of the battery
doesn't mean ****.

--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com