Original poster: DRIEBEN@xxxxxxxxxxxxxxx
Hey guys,
>From what I've gathered, it seems that the larger
high powered coiled require looser pri/sec coupling
than do their smaller NST powered counterparts to
prevent the racing sparks. Also, I've noticed that
if the SG starts improperly quenching (misfiring
and/or running "choppy") that this can also cause
racing sparks on an otherwise well built and well
tuned coil system.
David Rieben
----- Original Message -----
From: Tesla list <tesla@xxxxxxxxxx>
Date: Monday, September 11, 2006 0:21 am
Subject: Re: A search for a better primary
To: tesla@xxxxxxxxxx
> Original poster: "Gerry Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
>
> Hi Jim,
>
> Sounds like you have great performance with your 15K/120ma static
> gap
> setup. My 8 inch coil is running with the same power source but
> with
> a SRSG. I think the trick to increasing coupling without racing
> arcs
> is to not couple as much into the lower turns by increasing the
> clearance between the inner turn of the primary and the
> secondary. You seem to experiencing the same benifit with your 2
> inch clearance. Maybe you can even raise the primary (or lower
> the
> secondary) somewhat.
>
> Gerry R
>
> >Original poster: "Jim Mora" <jmora@xxxxxxxxxxx>
> >
> >Hi Gerry,
> >
> >My 8" 35.5" was one inch above a 15 degree 1/4" primary tapped
> near 15. Cap
> >was 1.5 ltr. I was running a RQ heavily blown gap that roared
> healthily when
> >it was up to voltage. The top hat was a 32"x8" with a 4"x12"
> lower dryer
> >duck siliconed to the big toriod which added much strength and
> additional>shielding. It was powered by two Transco 15/60 HP with
> a Terry filter and
> >safeties all carefully adjusted with HV - tuned with a freq gen,
> scope, and
> >freq counter. I always cranked it to 140v+ and the sparks did
> fly. It would
> >consistently strike a 6 foot target; and, without a breakout or
> target>flared chaotically outward, impressive, and very loud.
> >
> >My point is I used a 2" arc space (12" first turn) clearance and
> never had a
> >racing arc yet K was well in good range.
> >
> >Jim Mora
> >
> > P.S.
> >
> >Not many agree, but I believe the larger primary couples and
> rings higher
> >into the secondary coil reducing the very high currents at the
> base and
> >eases the quench which most agree on.
> >
> >In the interim (until the 12" is finished), I'm going to use this
> coil with
> >my pig and a 1/2" flat primary with as much arc space I can get
> and still
> >have a reasonable k factor. While being aware that I'll be near
> resonance>charging, as you pointed out - THANKS, I therefore will
> keep the break rates
> > >200 to prevent over-volting my new, tedious MMC. Having said
> that, I have >a
> >couple of construction easing ideas to share latter.
> >
> >
> >
> >-----Original Message-----
> >From: Tesla list [mailto:tesla@xxxxxxxxxx]
> >Sent: Saturday, September 09, 2006 9:58 PM
> >To: tesla@xxxxxxxxxx
> >Subject: A search for a better primary
> >
> >Original poster: "Gerry Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
> >
> >Hi All,
> >
> >I just finished part 3 of this exercise that makes an in depth
> >comparison between an "existing" primary located 1 inch below the
> >bottom turn of the secondary that has a 1 inch space from the 8 inch
> >coil form and a "new" primary design that is located 1 inch above
the
> >bottom secondary turn but with a 3.5 inch clearance from the same
> >coil form. The existing primary has demonstrated a tendency for
> >racing arcs that prompted this search.
> >
> >Part 2 showed a simulation method that not only seems to predict the
> >high stress levels needed for racing arcs, but also predicts where
> >they would breakout. The prediction agrees with observation. The
> >simulation, as shown in part 3, also shows what happens when the TC
> >is out of tune.
> >
> >In part 3, it is shown that even though the new primary has a
greater
> >overall coupling, it also has less stress on the coil reducing the
> >tendency for racing arcs, and also shows greater tolerance for
> >mistuning. If this approach works out, this may be a way to avoid
> >racing arcs and yet get higher coupling and higher topload
> >voltage. This may also be a way to improve the energy rise time at
> >the top load and facilitate better streamer formation. The
following
> >are the links to the most recent of each of 3 parts. Please read
the
> >papers and comment.
> >
> ><<http://hot->
streamer.com/temp/GerryReynolds/In_Search_for_a_Better_Primary1.>http:/
/hot-streamer.com/temp/GerryReynolds/In_Search_for_a_Better_Primary1.
> >pdf>http://hot-
> streamer.com/temp/GerryReynolds/In_Search_for_a_Better_Primar>y1.pdf
> >
> >http://hot-
> streamer.com/temp/GerryReynolds/A_Search_for_a_Better_Primary2.pd>f
> >
> ><<http://hot->
streamer.com/temp/GerryReynolds/A_Search_for_a_Better_Primary3.p>http:/
/hot-streamer.com/temp/GerryReynolds/A_Search_for_a_Better_Primary3.p
> >df>http://hot-
> streamer.com/temp/GerryReynolds/A_Search_for_a_Better_Primary3>.pdf
> >
> >Gerry R.
> >
> >
>
>
>
>