# Re: Who needs a quenching gap ?

```Original poster: Terry Fritz <twftesla-at-uswest-dot-net>

Hi Antonio,

You are right that one can make the end of the notches "cleaner" by fine
adjustments of K so that the waveform has a nice null point.  I have played
with this a little to try and help quenching but it never made any
difference in my tests.  However, I didn't try really hard either.  I find
that fine adjustments of K can be done so that the waveforms do look better
an the end of the particular notch for whatever good that may do.

Those interested in such things may wish to check out my paper at:

http://hot-streamer-dot-com/TeslaCoils/MyPapers/sgap/sgap.html

Cheers,

Terry

At 10:22 PM 12/8/2000 -0200, you wrote:
>Tesla list wrote:
>
>> Original poster: "Finn Hammer" <f-hammer-at-post5.tele.dk>
>
>> I believe it is possible to determine the coupling from this trace, how
>> is that done?
>
>To have an idea, I list below where is the first notch of the primary
>voltage for the first optimum coupling coefficients. Look at the
>at the end, facts that I have just observed:
>
>First series:
>These are the most usual modes, with total energy transfer at the 1st
>envelope notch.
>
>mode	k		cycles (primary)
>1,2	3/5	= 0.600	1.0
>2,3	5/13	= 0.385	1.5
>3,4	7/25	= 0.280	2.0
>4,5	9/41	= 0.220	2.5
>5,6	11/61	= 0.180	3.0
>6,7	13/85	= 0.153	3.5
>7,8	15/113	= 0.133	4.0
>8,9	17/145	= 0.117	4.5
>9,10	19/181	= 0.105	5.0
>10,11	21/221	= 0.095	5.5
>11,12	23/265	= 0.087	6.0
>12,13	25/313	= 0.080	6.5
>13,14	27/365	= 0.074	7.0
>14,15	29/421	= 0.069	7.5
>15,16	31/481	= 0.064	8.0
>16,17	33/545	= 0.061	8.5
>17,18	35/613	= 0.057	9.0
>18,19	37/685	= 0.054	9.5
>19,20	39/761	= 0.051	10.0
>20,21	41/841	= 0.049	10.5
>
>Second series:
>There modes result in total transfer at the -second- envelope notch.
>I don't list the modes equivalent to the 1st series.
>
>mode	k		cycles (primary)
>1,4	15/17	= 0.882	2.0
>2,5	21/29	= 0.724	2.5
>4,7	33/65	= 0.508	3.5
>5,8	39/89	= 0.438	4.0
>7,10	51/149	= 0.342	5.0
>8,11	57/185	= 0.308	5.5
>10,13	69/269	= 0.257	6.5
>11,14	75/317	= 0.237	7.0
>13,16	87/425	= 0.205	8.0
>14,17	93/485	= 0.192	8.5
>16,19	105/617	= 0.170	9.5
>17,20	111/689	= 0.161	10.0
>19,22	123/845	= 0.146	11.0
>20,23	129/929	= 0.139	11.5
>22,25	141/1109= 0.127	12.5
>23,26	147/1205= 0.122	13.0
>25,28	159/1409= 0.113	14.0
>26,29	165/1517= 0.109	14.5
>28,31	177/1745= 0.101	15.5
>29,32	183/1865= 0.098	16.0
>31,34	195/2117= 0.092	17.0
>32,35	201/2249= 0.089	17.5
>34,37	213/2525= 0.084	18.5
>35,38	219/2669= 0.082	19.0
>37,40	231/2969= 0.078	20.0
>38,41	237/3125= 0.076	20.5
>40,43	249/3449= 0.072	21.5
>
>In general: a=integer, b=a+odd integer:
>
>mode=a,b;  k=(b^2-a^2)/(b^2+a^2); full primary cycles=b/2
>Or k~=1/(2*cycles), as mentioned in other posts.
>
>Note the curious fact that it's possible to have total energy transfer
>at the 1st notch (modes a,a+1), at the second notch (modes a,a+3), or
>at the nth notch (modes a,a+2*n-1).
>Close to each optimum k for total transfer at the 1st notch there are
>two values of k the result in total transfer at the second notch.
>Close to these ks there are other values that result in total transfer
>at the 3rd noth, and so on. There is also a set of high optimum
>couplings
>corresponding to modes 1,1+odd integer, and the families that appear
>around them.
>I don't believe, however that a real spark gap is sensitive enough
>to the primary energy to quench precisely where the primary energy
>disappears, because the differences among the primary energies at all
>the
>envelope notches is small. But there is a tendency for this.
>
>Antonio Carlos M. de Queiroz
>
>

```