First, I have a '73 with the ignition converted to Duraspark. I am wired per George's Duraspark II wiring diagram.
I was running some electrical checks on my car before proceeding with more assembly - I believe things are wired correctly, but wanted to check things.
For initial testing, I just hooked 2 AA batteries to my main battery terminals, and measured voltages throughout the system. My thinking was, if I had a catastrophic short, then I would read 0 VDC, when I should be reading about 2.2V, but a couple of AA batteries wouldn't burn anything up.
I got through my initial round of checks with no problems, all the voltages were about what I expected.
After that, I hooked up my battery (12 V) to the battery terminals, and started stepping through the checks in the engine bay.
After a couple of minutes, I smelled something hot, so I disconnected the Battery.
I felt around back there, and realized that the smell was coming from my ballast resistor. This is fused, with a 15A Fuse (Need to verify the amperage), but.......
...if things are hooked up right, and my distributor is "closed" (effectively) and the coil is 1.1 Ohm, and the Ballast is 1.1 Ohm and there is no current limiting or resistance in the Duraspark Module, I should be pulling 12 V / (1.1 + 1.1) = 5.45 Amps through the ballast resistor.
If the Coil and the Ballast have about the same resistance - the Ballast resistor should be dissipating P = I * V = 5.45 * 6 = 32 Watts.
QUESTION: Is this right? Am I just unlucky, and because the engine is at TDC, and the distributor, and the stars are in alignment, I am drawing charging current through my Ballast / coil?
Are are ballast resistors supposed to get so hot you can smell them?
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