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more resonance experiments.

Greetings,

Last night I got to play around with the new equipment and coils some
more.
I wanted to double check my readings on the new coil that I made and
also on the tesla coild that I have that I know works.
I connected the signal generator and scope in the following manner:


  scope <----3
             3
             3
             3  950 turns, 4" dia, 20" long
             3
             3
             ---------> Square wave generator red lead
  <------------------------------------------->
    ground of scope probe and sig. gen. black lead connected

With this setup, I did indeed see some sort of a maximum amplitude
sine wave at 114.7 kHz (used my signal counter for the value).  I also
saw a lesser amplitude peak around 910.6 kHz.  Unfortunately, I didn't
connect this coil up the way that Mark Graalman suggested.  I'll try
that soon.

I tried the same configuration above on a secondary that works.  This
secondary is 12"x3" with a 12"x3" toroid on top. I connected the probe
to the toroid and the signal generator to the ground end of the
secondary.

                     OOOOOOO <---Toroid
                        3
                        3 <----Sec.
                        3
                        3
                        3
                        3
 to scope <-------------3---/\/\/\/\/\------------------------> to generator
                              ^ 1000 ohm carbon resistor
   scope  <---------------------------------------------------> generator
   ground                                                       ground
 
This method gave me a much more reasonable value of 382kHz.  When I
used the scope to view the wave form, I saw a lot of harmonics at a
low amplitude.  It looked essentially like a small band of green on
the scope.  When I adjusted the frequency in either direction, the
amplitude went way up (a good sign).  Next, I looked at the frequency
for the primary circuit.  I shorted out the spark gap and put the
generator on either side of the cap and put the probe on the cap
terminals as well.  I observed a maximum amplitude at a frequency very
near 382 kHz!  This was consistent with reality, as this coil works
when powered up.  One think that I found interesting was that when I
found the maximum point in the primary tune, the signal counter jumped
to around 900kHz.  This was unexpected, but readily reproducible.
 
Chip