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Re: Pigs and other barnyard experiments.

Sometimes pigs can fly, but most of these are three phase 400 Hertz.  As to
your question about Jacobs ladder erratic operation, I offer you this
observation.  Still air is absolutely necessary, any draft will cause
inconsistent or erratic operation.  This is due to the physics of Jacobs
ladder operation.  The arc is jumped at the narrow base and then air is
ionized, as this happens heat is generated.  Heat rises, ergo a gap of
ionized ( conductive) air rises carrying with it the arc.  Any disturbance
of this ionized gap of air and the arc sputters and eventually extinguishes.

Keep em flyin.                T.W. Helwig

-----Original Message-----
From: Tesla List <tesla-at-pupman-dot-com>
To: tesla-at-pupman-dot-com <tesla-at-pupman-dot-com>
Date: Saturday, October 03, 1998 8:24 PM
Subject: Pigs and other barnyard experiments.


>Original Poster: "Bill the arcstarter" <arcstarter-at-hotmail-dot-com>
>
>Coilers,
> Here are some results of some pig tests I performed tonight.
>
>First I attempted to measure the inductance of the pig primary, from the
>0 to the 120 lug on the LV side.  My battery-powered LCR meter indicated
>1.5 mH, which is clearly much too low.  I suppose the little meter just
>doesn't put out enough juice to overcome core hysteresis in the iron.
>Comments??
>
>Next I measured the pig's no-load current by applying 120v to the 0-120
>lugs (with a 65 mH limiting reactor in series to keep accidents down if
>the HV side should flash over).  The no-load current was 0.69 amps,
>which (assuming 90degrees phase angle) yields a calculated approx. 0.45
>H of core inductance, a much more reasonable value.  Comments??
>
>Oh, the primary's resistance is on the order of 0.04 ohms, real real
>tiny!
>
>Then I tried a bit of Jacob's ladder action.  First I used my 0.065 H
>limiting inductor in series with the pig's 120v input.  Note - this
>0.065 H inductor is an un-shorted-out MOT primary.  The Jacob's action
>was sort of erratic, but more strangely, each time I'd get an arc out
>the HV side of the pig, I'd hear a "bump" coming from the variac and the
>MOT. Is this normal???  I was powering the whole thing off a 10A variac,
>if this makes a difference...
>
>Finally I tried using a resistive ballast, in the form of an old toaster
>oven in series with the pig.  Setting the oven on "Toast" provided the
>most power to the pig :) .  The Jacob's Ladder action was much much
>smoother this way.
>
>I though most people had the best results when using inductive limiting.
>This was not the case with me.  What is going on here?  Average current
>using the toaster oven ballast was about 12 amps, and average current
>using the MOT was something like 6-8 amps, although it swung around
>wildly. In a previous experiment I'd determined that the V vs I curve of
>this MOT core was rather nonlinear, ie, I increases rapidly with
>increasing V.
>
>I can only assume that once the HV arc ceased to conduct, there was
>still a current flowing in the MOT (?).  This current would then
>collapse, causing the "thump" noise from various components...  Any
>clues??
>
>-Bill
>(chicken of my pig lest it gets my goat and I become BACON!)
>Starting arcs in Cinci, OH
>http://www.geocities-dot-com/CapeCanaveral/Hangar/6160
>
>
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>