Subject: Re: Frequency?
Date: Tue, 6 May 1997 11:34:25 -0400
From: Dave <djb-at-erie-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
At 12:18 AM 5/4/97 -0500, you wrote:
>Subject: Re: Frequency?
> Date: Sat, 3 May 1997 13:35:34 +0500
> From: "Alfred A. Skrocki" <alfred.skrocki-at-cybernetworking-dot-com>
> To: Tesla List <tesla-at-pupman-dot-com>
>Welcome to the list Dave! Generaly most people don't design a Tesla
>Coil to operate at any specific frequency. Most people want the
>biggest spark they can get so they build the largest coil they can
>afford and contain. It is wise for a beginner to start small where
>mistakes are more forgiving (get shocked by a neon transformer and
>you learn a new dance, get shocked by a pole pig and you are DEAD).
>The larger a Tesla coil is the lower the frequency it will resonate
>at. Lower frequency all other variables being equal will give you
>bigger sparks than a higher frequency. I have built some very high
>frequency coils and their discharge looks more like a fuzzy plume
>than a spark.
>
Thanks guys for clearing that up. I was thinking for some reason that
the
frequency had something to do with how well sparks travelled through
air.
Now I hope you guys don't mind another question or two? I am a "newbie"
with
this and don't know if this list is just for advanced coilers/ists or
not?
Seems most of the discussions are just a bit over my head at this point
in
the game.
Ok here goes...I noticed while playing around with TESLAC that as
secondary
length increases for a given aspect ratio, so does Q and Ls (Inductance
of
the secondary). This seems to be good. However something is telling me
that
as the secondary gets taller and taller, that there will be less
coupling
and greater losses between the primary and it's windings. Does not seem
good
to me now. Is there a tradeoff here between length, Q, Ls, and coupling?
Now, if we figure out what length of secondary to choose...I noticed
that as
we made the secondary wider and wider, that Q and Ls also increased.
This
seems good to me too, however I am wondering if there is a limit to how
wide
we can make our secondary for a given coil length? I think the program
only
calculated between a 1.5 and 4.5 aspect ratio, and I am certain I read
that
the aspect ratio should be 3-4. It seems to me that an aspect ratio of 1
would produce an even higher Q and Ls. Isn't this what we want?
Now, lastly, if we choose a secondary length and diameter...my next
question
is on the appropriate wire size to use. Looking again at TESLAC, for a
given
coil size, if I choose a larger wire diameter, then Q increases, however
Ls
lowers. So do we have another tradeoff here? I am guessing that we use a
wire size that will allow the highest "average" of the two? If not, how
does
Q and Ls effect the output of the coil? Also, what type of wire do most
people use for their secondary?
Well, that's about all the questions I have on the secondary for right
now.
Sure hope someone can shed some light on this for me. Haven't even begun
to
look at the primary, caps, etc. So much to know, so much to learn, so
little
time... Can't wait til I get the books I ordered. Thanks guys for your
help.
Dave