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Re: Dramatic Performance Drop After 5 Seconds?
>My coil when at 3/4 to full power will run really nice for
>1-5 seconds and all the sudden the 12" - 14" streamers turn
>into little 1/2" streamers, and the sound changes to a real
>tinny sound. If I wait a few minutes and turn back on, it
>repeats.
A friend of mine and I had a coil that behaved exactly as
you describe. We weren't using the sort of caps you are.
We were using some very old doorknobs salvaged from
a piece of equipment likely discarded from the Stanford
Linear Accelerator Labratory.
The coil would run well for a few seconds then behave
erratically with reduced output. There were other
problems that indicated that a resistance had appeared
in the tank circuit somewhere.
In the end it turned out that the caps were shorting
internally as they heated up. High impeadence shorts
that, when bridged, shifted the apparent value of the
capacitors. When they cooled down they returned
to their original value.
When they were cool the coil behaved well.
By the way, "hot" was really barely warm. They only
got a touch above room temperature, but that is all
it took.
If you have a way to measure the value of your
capacitor I'd say check it before a run and then immediatly
after. If it shifts noticably I'd consider going to a different
sort of cap.
John