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Re: TCBOR Magnifier 11-E Specs

Hi all,
        On this...

RH> Primary Qs have not even been a remote thought here and therefore
RH> I have no instrumented, experimental data.

EH> Here's where I'm coming from though - Malcolm has done some
EH> measurements which seem to show that primary circuits  have Q's of
EH> about 10 no matter what L,C combination one uses. Well this seems
EH> to imply the spark gap as the culprit then for the major energy
EH> loss in the primary circuit. It also, not suprisinly, behaves in a
EH> non-linear way to the current passing through it. Morecroft (I
EH> think) says that spark gap circuits tend to decay linearly, rather
EH> than exponentially as in pure resistive circuits. Have you( or
EH> others) seen this?

I have JUST had the benefit of reading some of the Corum's work on 
this and they mention this too. However, not only does my scope show
that the decrement is far from linear, but one applies a logarithmic
formula to calculate the Q. It may be that this formula is no longer
applicable in the light of this, BUT, in more detail, here's what I
was able to do with the storage scope. I was able to capture a 
waveform for one LC combination, store it, change the LC combination 
completely, adjust the scope timebase so that the new frequency
occupied the same X axis length, capture that, then SUPERIMPOSE the
stored waveform on top! They matched cycle for cycle and I tried this
with a number of combinations.

Malcolm