Re: Hehe, This is coo coo! Was "I give up!"

[Terry Fritz <twftesla-at-uswest-dot-net>]

Hi Garry,

        I felt sad at hearing of your frustration with your coil, but I could
not think of anything helpful to say...  Tesla coiling is a complex and "gnarly
thing" that is not easy...  But I figured, if you had gone this far, you were
hooked and could not let go ;-))  He he he...

I have had a few disaster coils that I have had to carry out to the trash
collection (under the cover of darkness) over the years, but your set up sounds
pretty good.  Probably just a matter of straightening a few details out.

This "works one time, but not another" "thing" is really very interesting!  I
would first think of humidity or water vapor "getting to something" as the
cause.  Your coil's problems sound like a tuning issue and I would suspect the
primary capacitor.  Either the capacitor's value is drifting or something is
shorting it out.  If you are in a humid area and using wood, perhaps that is
the cause.  Spark gaps can also be very finicky.  Not much to them but they can
exhibit various behaviors for no really good reason.

It seems that very short streamers are caused by not having the primary and
secondary tank circuits tuned.  In your case the primary capacitor seems like a
likely point for the miss-tuning to occur.  I have made caps like yours with
wood parts that have had this 'coming and going' symptom.  Wood can act like a
resistor and vary with humidity, so that would be my first guess.

We have tools that can calculate the primary and secondary tuning given enough
information.  I don't quite know what to ask of you at the moment to fill in
the detail for that (long day at work, brain fried...) but it can be done.

My advice for the moment would be to look for where wood and high voltage come
together.  I don't know where you are, but humidity can do all sorts of odd
things...  I live in bone dry Colorado so "I" don't worry much about humidity.

Cheers,
        
        Terry




 

At 08:56 AM 8/22/00 -0700, you wrote: 
>
> After getting it tuned last night and fiddling with it and getting weak
> streamers and a week sounding spark gap, but some progress. I turned it off.
>  
> I get up this morning and I turn it on and fair sized streamers come out all
> over the toroid and the spark gap has a snap to it again. 
>  
> I didn't change a thing since the night before, I *swear* I didn't! Well,
> there is one thing different. I held my jaw in a different position. Could
> that be it? Maybe the fillings in my teeth are detuning and retuning the
> tesla coil? Who knows?