Wow the coil is inside the box! Something I didn't realize about the military distributor. That would be a great way to generate some RF!
You are an Artist no doubt.:) Your drawings both show about the same idea, an extra cap across the points.
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Wow the coil is inside the box! Something I didn't realize about the military distributor. That would be a great way to generate some RF!
You are an Artist no doubt.:) Your drawings both show about the same idea, an extra cap across the points.
The capacitor on the distributor input is isolated from the points by the inductance of the LV winding on the coil. I am pretty sure that the "condenser" is about 0.22 uF, 350 - 600 volt rating. I don't know what the "capacitor" value or rating might be, maybe someone will put one on a capacitance meter for us. It is probably rated about 200-volts or so.
If I had to eat any more crow, I'll grow feathers. Great breakdown explanation LarrBeard. Us non radio guys can learn something. When I first got the wagon, put a set of cheap plug wires on it. It ran good, but the AM radio would pick up the interference off the wires.
yuppsrr had same thing with my 39 ford before i rebuilt it..
still arguing with wire number 15, it comes out of loom and there aee two of them??? one goes into the ignition switch to power thru the light plug, the rest of the stuff, but got a hot wire after that??
Since that is a US Government contract vehicle, aren't the specs somewhere for the capacitor? Would that info be around? There are some Multi-Meter's with a capacitance setting, you could check a known good one. Of course if you had a known good one...
LarrBeard pointed out something. The noise capacitor is on the other side of the coil's primary winding. In stereo installs and what not it is common to put a cap on + supply lines. The bigger the better.
I'll see if I can hunt up the National Stock Number for the capacitor in the A.M.
have two distributors, one has a totally messed up corroded 24vdc intake to distributor the other is new, i rebuilt the distributor with the new parts i had, seems to be running fine timing at correct point.. was told by som3one i respect for his knowledge that the points if they burn up is because voltage to points too high? in a total 24vdc how can this be? and that if distributor not connected to mechanical vacuum at pump this might cause overheating in distrubotor?
On early points system, you would have a ballast resistor in between the key switch and the coil. On a 12 volt system, the resistor drops the voltage to 8 volts to help the points live longer. On a points system, in theory the small distributor caps would have a tendency to spark ark between poles, so the ballast resistor was implemented to reduce the voltage to prolong the life of the points. On the Chrysler big blocks that I had for the derby cars, I would remove the ballast resistor to send full current to the dual points distributor. With all the wide open throttle runs, I never had one failure of the points or coil. With the zoomy headers run through the hood, I could monitor how each plug was firing by the blue flame at the tip. The system was darned near bullet proof in my opinion, because these engines would really take a beating. Using GM products was much simpler. The HEI distributors were simple to wire, but they took up a lot of real-estate near the fire wall.
Now, the 24 volt distributor is designed to take the abuse of the 24 volts coming into the coil. The coil has a resistor built in, and will help the points live for a long time.
Doing a bit of research on the distributor in your A1, and with it's weather tight design, it does need forced air vented to the distributor to help to keep the coil cool. One line either coming off the fuel pump/vacuum pump or after the PCV valve will supply you with the negative pressure. The second line is plumbed into the air cleaner. This is why your distributor has two ports, intake and exhaust if you will.