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Re: [TCML] Odd VTTC Streamer Behavior

> Actually that all looks pretty nice from what I can see in the
> photo.  I don't know if that loop of wire hanging would
> make very much difference.  Are you saying the loop was
> part of the primary then it fell down?

I felt I had too many primary turns so I unwound it tested without cutting
the wire (for obvious reasons)  It's laying on the side to decouple it from
the secondary.

> When I spoke of hte size of the doubler cap, I wasn't
> refering to the reduction in spark length you saw.
> I was refering to the general problems you had at
> high power with spark splitting.
> I see too that  you're using the high mounted grid
> coil  such as Cameron used.  I also see that there  seems
> to be quite a few turns on teh primary.  Either that
> or it's rather thick wire.  How many primary turns are
> you using, and how many grid coil turns?

Actually it's both in this case.  8 AWG ~25 turns for the primary.  24 AWG
22 Turns for the grid coil.

>   What happens
> if you use a much lower position for the grid coil?

Nasty things; the coil starts getting very power hungry, and the sparks
start making bad sounds.  The thud sounds somewhat screechy, or it makes a
cracking sound.

> If you gradually lower the grid coil, does the spark
> length change gradually?

Yes, and if I go below a certain point the sound changes, and the coil
starts misbehaving.

>  Or does the spark vary
> up and down depending on height?  For example
> if you lower the grid coil about 2" does it have much
> effect?

There seems to be a point on the form where performance drops, and the coil
starts acting up if I go below that point.  There is also a point where the
grid is too far away and the performance drops.  I'll do some more extensive
testing this evening.

>  I'm thinking maybe you're taking advantage
> of various phase conditions by using the high grid coil.
> the high grid coil might be improving the sparks, making
> them generally more sword-like.
> John

I received my filament transformer yesterday, and installed it today.  This
is interesting because when I plugged it in and tested the coil for the
first time the performance was terrible.  I could not get the coil above 50V
without the sparks making a popping sound [which sounds really bad].  I
thought the filament looked a little bright, and sure enough the transformer
was running at 10.3V.  To remedy the situation I hooked the transformer up
to a variac and set it so that it was exactly 10V with the load of the lamp
applied.  When I started the coil back up it ran much better.  Better in
fact, than the coil was running with my home-made filament transformer.  It
was too bright for me to see what the sparks were doing, I could just hear
that the sparks were hitting the target more often than before.  That said,
I highly doubt the home-made filament transformer was the only cause of my
problems.  I haven't changed this filament transformer since I wound it, so
it was the same when I was pushing out 34" sparks.

It's also interesting to note that when I was running the coil with the new
filament transformer installed I noticed that the sparks had had little
streamers coming off the leader at 90 degree angles.  This is something I
remember seeing when the coil was performing well and throwing out 34" arcs.
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