[time-nuts] Maser 0.7 nsec jumps solved

Mike Monett timenuts at binsamp.e4ward.com
Fri Jun 3 12:37:26 EDT 2016

To All;

I found a significant error in the LTspice analysis. I was wondering how
the current could jump instantaneously at zero when the voltage is applied
at the peak. That violates magnetism.

It turns out it doesn't. When LTspice starts an analysis, it first
calculates the operating point. For the Sine voltage source at 90
degrees, it applies the full voltage across the load. In this case,
it was 169.7V across 1 ohm, resulting in 169.7 Amps. That is what
was plotted, and is a significant error.

I embarked on a search to find examples where switching at the peak could
reduce the inrush current. 

Out of 13 examples I analyzed, I found only one that involves unloaded

I found many references that discuss transformer inrush current caused by
core saturation. This is a serious problem as it puts stress on the
components and reduces operating life.

I could find no reference that states switching at the peak would reduce or
eliminate the inrush current. I also found most major suppliers do not
offer SSR's that will switch at the peak.

Obviously, switching at the peak would be worse for capacitive loads. 

This was a major project and turned out to take a lot more time and effort
than expected. For those who may be interested, the results are shown at



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