Hey 79Nautique

I am no 79Nautique but I have a bit of time this morning to start the replies.... A ballast resistor is there to limit the voltage you see accross the primary of the ignition coil to less than 12 volts, usually around 9. The coil is designed to run at nine volts so that you can get an effective spark during starting when the high current draw from the starter dips battery voltage to around nine. When the Ignition switch is set to run the ballast resistor is in series with the coil, when it is on start there is an additional wire that bypasses the resistor going right to the primary winding. That 3 or so extra volts might not sound like a big deal on the primary side of the coil, but its a 33 percent increase and can mean thousands of extra volts on the secondary side, it will work for a while, I have shorted a blown(or broken) ballast resistor to get home more than once but it won't last under load.

The condenser's function is a little less intuitive, it is a capacitor it lies across the points after they are opened. The opening of the points causes the magnetic field in the coil to collapse, the current from the primary circuit of the coil rushes out and charges the condenser the electric field of the condenser and the magnetic field of the coil bounce this current back and forth in a "damped oscillating LC circuit" (had to go to my old intro to EE notebook to look that one up). All this serves to extend slightly the length of the output of the primary coil past the opening of the points. I think most of that is right but I am a mechanical engineer not an electrical engineer.

As for coil matching on electronic ignitions my only reason is because the manufacturer says so... I would guess it has to do more with current limiting than voltage limiting... anyone else?

IMHO if your listening to the radio in a boat with a points style ingnition that doesn't have a condenser your going to have bigger problems than radio interference. If you can get it to run at all with the weaker spark, all the current rushing out of the coil on the low side after the field colapses that should be absorbed by the condenser is going to arch across the points making them toast in no time.
     I have seen some debate as to whether the condenser also plays an unintended role in RFI reduction but as they are on the low voltage of the coil I just don't see it being considerable. I do know cars have had condensers a lot longer than they have had radios so I am inclined to believe my intro to EE prof wasn't completely full of crap when he fed me the line about the "damped oscillating LC circuit". If he was someone let me know maybe I can get a tuition refund...
-Joe.

I believe the ballast resistor is installed to limit current across the points. 12-15volts will burn the points quickly. Most coils will handle 12-15 volts without issues, so most electronic ignitions eliminate the resistor (no points to burn), but do not require that the coil be replaced. With this said, I believe there are coils out that do not handle 12-15volts and may fail.

If your objective is to bypass the ballast resistor you can simply connect a jumping wire from one resistor terminal to the other.

It may be that the internal impedence of the conversion kit is high enough to limit current flow eliminating the need for the resistor. This would, of course, vary from manufacturer to manufacturer. (Points provide almost zero impedence to current flow when they are closed.)

It doesn't really matter what the condenser does with it's current - it can send the current to Pluto as long as the condensor does it's job and prevents the points from arching.

In actuality the condenser absorbs energy from the primary coil winding created by the collapsing magnetic field within the secondary (high voltage) side of the coil winding. (Thereby eliminating an arch that would otherwise occur across the points as they opened.) The condensor discharges through the points when the points close. During the dwell portion of the cycle the points remain closed allowing current to flow through the primary of the coil. It is during the dwell when a magnetic field is developed around the magnetic core of the coil. It is the magnetic field itself in which the energy is stored and released through the spark plug when the points open and break the circuit. During the dwell portion of the cycle, when the points are closed, the condensor is shorted out by the points, effectivly removing the condensor from the circuit. When the points first open the charge level in the condensor is at zero - there is no current available within the condensor, to be sent anywhere. Sorry all - I couldn't help myself from the lecture - teaching electronics is how I butter my bread.

No it wasn't, sorry for the confusion. It's just this topic has been talked about several times and like a most of us when we look at the instructions for anything we look at the diagrams and illustrations and install or build what we're working on. Only when and if we run into a problem or it doesn't work do we refer back to the installation instructions and there it clearly states the condition/test that have to be performed before you can by-pass the resistor in this case.

Ok correct me if I'm wrong which most likely I will be but as far as the resistance for the coil goes here's why V=IR voltage=current times resistance

So since the votage is constant under operating conditions (not during starting which can see a slight drop in voltage) the resistance of the coil effects the amount of current flowing to the electronics so if it is to large then you can fry the module, points, condensor and so forth. That's why manufactures specify the coil resistance for their particular set-up or distributor. Most are very close and almost all are commom.

it's these small little differances or specification from the manufacturers that get overlooked and can cause premature failure of coils, modules, points and condinsors and leave you scratching your head why you have to replace ign parts three times as often as your buddy does and you use your boat less.

I concur. I think all of the last comments are correct.

I had an old car in which the ballast resistor was bypassed by the ignitoin switch during starting. My CC is not wired this way. I think it is intersting. My belief is there is no "correct" or "in-correct" way to set this up. If we were racing the correct way would be the way that won.

So? Who knows? It may be the correct way is the way that results in the highest density of thongs per square inch. It should be noted that if the color of your carpet is neutral any color thong will look good laying on it. Anyone want to disagree with this?

J_I_H; Didn't understand a word of what you guys were talking about until you got to the "thongs per square inch" formula. It has been my experiance that thongs look good on your boat no matter what color your carpet or seats are. In fact thongs look good even if you don't have carpet.

john

Come on down 64. I'll be the guy ripping down Chocolate Bayou in a small old blue boat, grinning from ear to ear and leaving a small oil slick.

By-the-way, my new Acme prop just arrived. Now I guess I HAVE to pull the boat out of the water :(

No matter what the color of interior the boat has, the thong is stil going to look good and even better laying on the floor,

no tan lines ya know

Jim did you get the 470?