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Report on Scoping Work Coil

Hi all,
           I finally got around (and the guts) to scope my work coil 
running normally to see what its BPS is (special interest for Boris 
and John Freau). Ep is around 3J max for this coil. I have 
measured the gap umpteen times with a metered HVDC supply. I
have a few interesting things to report.
      I ran the scope in another room with a short aerial so it was 
mostly (I think) picking up secondary E-fields. A colleague was 
switching the coil on and off in bursts ranging from 1/2s to 1s or so 
on my say-so.
       The waveforms appeared mostly as high amplitude spikes with 
low amplitude ringing in between and long periods of silence, and 
timebase was variously set at 2mS to 50mS. I was able to capture 
the waveform and spread it out with the timebase setting while the 
storage capture was on hold.
       In general, BPS appeared to be 100. Sometimes, it appeared 
to fire twice per 1/2 cycle, other times it appeared to miss a beat 
(npi).
      First interesting thing: after initial attempts, I decided to try and 
reduce extraneous noise a bit and bypassed the two 1mH chokes 
between the transformer secondary and the gap. The first thing my 
mate reported to me was that the spark length increased. After 
getting a grip on what he was saying, I looked for myself and sure 
enough, the coil was reaching out and attaching all around. Max 
strike distance was somewhere in excess of 3.5' regularly and over 
4' occasionally. 
     A bit later, I decided to try some modest airblast in the gap. This 
was mild at first but turned up incrementally in between switch-ons. 
The tone of the coil changed somewhat when the blast was getting 
high and started to become erratic (and poor output as a 
consequence). Just before that setting when the coil was firing 
steadily, there was a noticeable mains-f related buzz in the arcs. 
The output appeared to improve further at a somewhat more modest 
air blast and was better than with none.
 
       Even supposing that the scope was lying and the thing was 
firing at 200BPS, that is still a primary power of around 600W for 
4'+.  All this with a simple single 1/2" electrode W-C static gap.
Is anybody out there keen on duplicating this coil and conducting 
their own investigation?  I am restricted in both space and 
opportunity to run it since I no longer own it.

Regards,
Malcolm