Why is the coil being weird???? (fwd)

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---------- Forwarded message ----------
Date: Wed, 07 Nov 2007 21:49:41 +0000
From: jhowson4@xxxxxxxxxxx
To: tesla@xxxxxxxxxx
Subject: Why is the coil being weird????

I have been tinkering with my coil for a while now and it has been acting weird since the day I built it.  but it is just starting to get on my nerves.

So basically
When I run my coil at first if is good.  producing 30" sparks lots of noise etc.  
But after about 5-6 seconds it just craps out.  The spark gap stops making the normal loud spark gap sounds and it starts to make a really quick softer sound.   Like the one the tv makes when there is no channel and just static.  At the same time the sparks length drops to about 4".   
I turn it off.  let it chill for like 30 seconds and then it does the same thing.   If I turn it off and don't let it chill it just does it quicker. 
Very annoying.  
I am currently using 5 obits in parallel and 2    .005uf home made capacitors.  The spark gap is 2 bolts less than 1/4" apart in a tube that is connected to the blowing end of a vacuum.  The frequency is about 600kHz.  
Any ideas and  help will be great.

Many thanks,
Jay Howson