RE: First THOR measurement results

["Lau, Gary" <Gary.Lau-at-xxxxxxxxxx> (by way of Terry Fritz <twftesla-at-xxxxxxxxxx>)]

Hi Marco:

I don't know if this might be related to your coil's performance dropping
off with time, but I wanted to mention it.  I noticed in the picture of your
protection network that you are using just an L-C filter.  This L-C circuit
will oscillate strongly at it's parallel resonant frequency each time your
gap fires.  Normally folks use a series resistor to add losses to this
circuit to accelerate the ringdown period following each bang.  The
resistors of course add losses to the circuit, and even so, there will still
be a significant oscillation in this L-C, initially spanning the full
amplitude of the applied voltage.  R-C networks are now favored for this
reason. This high-voltage oscillation will be applied directly to the output
of your SMPS, and I don't know what impact this will have.  If there is a
feedback loop to sample and regulate the voltage, it could be introducing
some serious noise and messing up the regulation. 

Regards, Gary Lau
Waltham, MA USA



> Original poster: "Marco Denicolai" <Marco.Denicolai-at-tellabs.fi> 
>
> Hello everybody. 
>
> Eventually I got everything setup and working, in order to measure the
THOR
> TC 
> performance. 
>
> I did it today and I stored in a temporary web page the most significative

> oscilloscope snapshots. The address is 
>
> http://www.saunalahti.fi/dncmrc/work/tempmeas.htm
 
snip