Re: Rotor BPS
Subject: Re: Rotor BPS
Date: Sat, 31 May 1997 08:38:14 -0400 (EDT)
From: richard hull <rhull-at-richmond.infi-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
>Hello DR. RESONANCE, Richard Hull & All:
> I have a question that I hope can be directed at both of you and
>group based on comments by you, read over the last month or so. First,
>a short update on my situation--I've basically made little progress on
>my new coil due to the record cold and rain in south eastern
>Wisconsin--worst since 1888!
> O.K., the point made in the post above, about the secondary
>inches above the primary and I believe Richard also mentioned something
>about 3-4 weeks ago that led me to understand most of the time you
>avoided raising the primary above the very bottom of the
>secondary---that is where I am real curious.
> Finally the question-- my present understanding is that you must
>based on the posts be elevating the secondary to a point where your K
>must drop down to a low level, guessing maybe .08, or .12??? Have I
>missed the boat here? I had expected with what I had learned in working
>with my 8" coil tuning process that raising the primary would provide
>better output, assuming the system design allowed for the greater K.
>Now the discussion is suggesting another point that I don't have a clear
>view/understanding of right now. Boy, I only have 3" of clearance right
>now when I roll it out of the garage and that's without the toroid!
>What I am wondering is that with the bigger coils, is there less
>attention to the K value and more to eliminating pri/sec arcs by
>increasing clearances? I have a 2 1/2" air gap between the pri/sec
>windings and thought this would be O.K.
> They are actually predicting that the rain will stop (I really
>believe it) and it will reach 75 Degrees F this weekend. I have dropped
>the primary to be on the same plane as the lowest/first turn of the
>secondary and plan to smoke test this weekend. If the mood strikes you,
>any comments would be of interest. Thanks in advance!
Most really large coils can use a coupling of .25 and work fine provided
spark is handled adequately. Your coupling sounds OK.
Raising the primary up around the secondary is always a dangerous game.
secondary voltage on the turns rise fast. Very fast and you are asking
trouble with primary/secondary arc over.
A helical archemedian spiral in an inverted cone is just the best
for large coils. A 15" diameter coil should have about a 56X12 toroid
shield the primary system properly and take up and distribute the power
such a large resonator.
On Nemesis which was almost identical to your new large system, I had
1.5" separation between the first secondary turn and the inner first
turn. I never sparked over at .28 coupling. The system did require a
ground ring around the 48" diameter primary as the arcs were quite long
often arced in huge circling air arcs to this point.
If anyone insists on elevating a primary after construction, they should
prepared for primary-secondary arcing. If it does not occur and the
works great, they are among the blessed!
Richard Hull, TCBOR