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Re: S.G. Replacmt-update
Bert Hickman wrote:
>
> Tesla List wrote:
> >
> > FutureT-at-aol-dot-com wrote:
> > >
> > > Richard, Bert, All,
> > >
> > > Regarding Lou Balint's experiment in which he used a transistor to replace a
> > > spark gap in a TC, and used ferrite to boost the coupling to k = .84, and in
> > > which optimal quench time (which prevented splitting of frequencies) was
> > > originally found to be 1.2uS, which was surprisingly rapid: ( I
> > > unfortunately forget the original freq. and can't find the original post. :(
> > > )
> > >
> > > In a new test, Lou set up everything the same as before, but varied the
> > > voltage to the transistor base. At some lower voltage setting, the optimal
> > > quench time now ranged from 3uS to 5uS depending on the voltage. The
> > > original voltage still gave a 1.2uS optimal quench time. He suggests that
> > > more work is needed. This was a very quick test, so voltages, turn on/off
> > > points, Q, etc were not monitored. Unfortunately, Lou stated that he does
> > > not plan to continue along this line of investigation, due to other research
> > > demands.
> > >
> > > Happy and "quenchy" coiling,
> > >
> > > John Freau
>
> John,
>
> Thanks for the update! The data from your earlier post is summarized
> below (as well as a copy of the original). Sounds like the good news is
> that we DO, indeed, go monochromatic at shorter quenchtimes, but it's
> not clear that the predicted quenchtime values agree with experimental
> measurements.
>
> The unadjusted (for Q) theoretical quenchtimes with a "perfect" switch
> are shown below. Lossier switches will reduce the Q in the primary
> circuit, shortenning the times from that shown. However, without having
> a feel for the primary Q with the transistor "gap", it's hard to say
> whether experiment matches theory quantitatively. Sounds like the books
> not yet closed on this area, but the results are still encouraging!
> Maybe when you get your spectrum analyzer running... :^)
>
>
> (kHz) (uS) (uS) (Unadj)
> k Fo Tq New Pred Tq
> ---- ---- ---- --- ----
> 0.102 114 12-70 - 43
> 0.573 92 5-8 - 9.5
> 0.843 64 1.2 3-5 9.2
>
> Safe coilin' to you, John!
>
> -- Bert --
>
> Older Post:
> =======================================================================
> Bert H,
>
> I just spoke to Lou Balint who has completed some tests for 1st notch
> quenching, using a spectrum analyzer. Bert, let me say that the news
> fully
> supports your viewpoint. I was surprised, but glad, since it means that
> the
> threat of racing sparks should be minimized--which is something we can
> all
> rejoice about. Now we just need the gap that can do the job.
>
> In Lou's first test, he used a loose coupling of k = .102, he obtained
> what
> appeared to be a monochromatic output when "quenching" (actually he used
> a
> transistor to simulate a spark gap) at anywhere from 12 uS to 70 uS.
> Center
> freq. was 114 kHz.
>
> The next two tests at a higher k value are intriguing. First a k value
> of
> .573 was used, and he obtained a double humped spectrum when using long
> quench times such as 10 uS, 25 uS, 50 uS, 100 uS , etc. As the quench
> time
> was gradually reduced, the side frequencies weakened, and the center
> frequency strengthened. By the way, the optimal quench time for this
> set up
> was 5 uS. At 5 uS quench ONLY the center frequency was seen. It was
> not
> until around 8 uS that the side frequencies began to appear. As the
> quench
> time was increased, the side frequencies got stronger, and the center
> frequency weakened. The center frequency in this set up was 92 kHz,
> when I
> speak to Lou again, I'll ask him for the measured side frequency values.
>
> Lou did a third test at k = .843, the center frequency was 64 kHz, and
> the
> optimal quench time 1.2 uS. Again, the side frequencies appeared as the
> quench times got longer in a similar manner to the above test.
>
> The side frequencies seemed to gradually become stronger as the quench
> time
> lengthened, this supports all of our observations that racing sparks
> gradually increase as quenching gradually fails.
>
> It is good to hear of actual real-world test results in this matter.
> Thanks
> Lou for your speedy efforts in the matter. And thanks Bert for all
> your
> info and for being persistent in the matter, and your PSPICE data seems
> vindicated. And thanks to the other list members who commented on this
> matter.
>
> I was getting set up to do some spectrum analyzer tests, but I am being
> delayed by an analyzer that is either insensitive, or faulty. I will
> however
> continue to attempt to reproduce these happy results.
>
> A good day in Tesla Land,
>
> John Freau
>
> ========================================================================
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