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Posted by: tornik550 Aug 15 2012, 03:37 PM

What does the black box in the alternator do and is it needed? I have heard several times that it dampens interference with the radio. I do not have a radio so do I need the black box?

Posted by: tim_nd Aug 15 2012, 04:22 PM

Not needed, its the 2nd part of a LC circuit to change and alter frequency's.

Posted by: Tom Aug 15 2012, 04:58 PM

Yes it is needed. I believe I mentioned this before on another thread. It is used to dampen out the ac component on the DC after it has been rectified from the AC the alternator puts out to the DC the battery needs for charging. Typically an alternator voltage rectified to DC has up to 10% ac component before being filtered. Ie, without the filter, you may have as much as 1.3 volts ac component superimposed on the DC level, also known as ripple. Not good for electronics and definitely bad for stereos.
Tom

Posted by: SLITS Aug 15 2012, 05:05 PM

Damn, and all these years I have run without them.

Posted by: tim_nd Aug 15 2012, 05:23 PM

The 10 percent ripple AC current seems abit high, it's possible one of your 6 diodes were faulty.

Posted by: SLITS Aug 15 2012, 05:45 PM

Anyway, found it on AA's site ... 021 903 295 Suppressor Condenser ... $11.80 ea

Posted by: Cap'n Krusty Aug 15 2012, 05:47 PM

And just look at you. THAT should be a lesson for all of us. Talk about an electrical "short"!

The Cap'n

Posted by: tornik550 Aug 15 2012, 05:59 PM

I tried. They are nla.

Can a faulty black box cause a fire on the starter to alt wire?

Posted by: tim_nd Aug 15 2012, 06:04 PM

Yes, capacitors are the weakest link of any electrical component. The dieletric often degrades over time, and these can short out to gnd.

Posted by: SLITS Aug 15 2012, 06:07 PM

Nice shot admidships my friend

Posted by: KELTY360 Aug 15 2012, 06:27 PM

Posted by: tornik550 Aug 15 2012, 07:19 PM

Is there a way to test the "black box"

Posted by: kg6dxn Aug 15 2012, 09:09 PM

With an LC meter if you know the correct Farads it should be.

Posted by: brant Aug 15 2012, 09:51 PM

I've been missing John around there.
I hope you were on vacation or something good

Nice come back!

b

Posted by: Cap'n Krusty Aug 15 2012, 10:22 PM

Thanks! I'm dealing with moving my parents to a site much closer, and am hoping to the the 400 mile round trip each week, as well as the frequent 4 day weekends and no internet services. This has been going on, with increasing frequency, for nearly 2 years, and Lyn, I, and my 2 sisters are physically and emotionally as beat up as we can stand. Couple more weeks, and I'll be back to the old equal opportunity harrasser you know and love.

The Cap'n

Posted by: brant Aug 15 2012, 10:25 PM

wow...that is tough
I can't imagine
if there is anything I can do

hang in there

brant