Hi All,
After having asked more than once for simple characteristics, taken
Tom's speculative offering of 300µH (to which Yuri neither accepted
nor rejected, nor offered amendment to, nor any value of his own, nor
attempted to confirm or reject through his correspondence); I settled
down to hammering through the values to make it ring using the other
speculations of simple characteristics that remain wholly undisclosed
(see enumeration above).
The valuation offered by Tom was easily 1000% high. That I suggested
that my model did not resonate came to no response by Yuri, who was
quick to accept testimony of there being a current differential (which
was also in reverse characteristic to those so-called measurements).
Instead, I used what metrics were offered in the casual report and by
evidence of photography to mock up the following:
0.375" Diameter copper (with losses) radiator length at 92";
a ground field of 60 #12 copper (with losses) radials;
a 36.8267µH lumped coil (no losses attributed through R, no C);
the lumped coil placed at the 46th inch (49.45%);
the antenna placed over real ground;
ground is of medium characteristic;
the entire antenna/ground plane is 6" above actual ground;
that comes to the following current distribution:
1 W2E1 1 0.00
2 1.0005 0.00
3 1.0012 -0.01
4 1.0019 -0.02
5 1.0027 -0.03
6 1.0035 -0.03
7 1.0043 -0.04
8 1.0051 -0.05
9 1.006 -0.05
10 1.0069 -0.06
11 1.0079 -0.06
12 1.0089 -0.07
13 1.0099 -0.07
14 1.011 -0.08
15 1.0121 -0.08
16 1.0132 -0.09
17 1.0144 -0.09
18 1.0156 -0.10
19 1.0169 -0.10
20 1.0182 -0.10
21 1.0195 -0.11
22 1.021 -0.11
23 1.0224 -0.12
24 1.024 -0.12
25 1.0256 -0.12
26 1.0273 -0.13
27 1.029 -0.13
28 1.0309 -0.13
29 1.0328 -0.14
30 1.0349 -0.14
31 1.0371 -0.14
32 1.0394 -0.14
33 1.0418 -0.15
34 1.0445 -0.15
35 1.0473 -0.15
36 1.0503 -0.16
37 1.0535 -0.16
38 1.0571 -0.16
39 1.061 -0.16
40 1.0653 -0.16
41 1.0702 -0.17
42 1.0759 -0.17
43 1.0826 -0.17
44 1.091 -0.17
45 1.1039 -0.17
46 1.1224 -0.18
47 1.0841 -0.18
48 1.0513 -0.18
49 1.0231 -0.18
50 .99652 -0.18
51 .97101 -0.18
52 .94623 -0.18
53 .92201 -0.19
54 .8982 -0.19
55 .87475 -0.19
56 .85159 -0.19
57 .82863 -0.19
58 .80587 -0.19
59 .78328 -0.20
60 .76083 -0.20
61 .73849 -0.20
62 .71627 -0.20
63 .69412 -0.20
64 .67205 -0.20
65 .65004 -0.20
66 .62807 -0.21
67 .60614 -0.21
68 .58425 -0.21
69 .56237 -0.21
70 .5405 -0.21
71 .51863 -0.21
72 .49675 -0.21
73 .47485 -0.22
74 .45294 -0.22
75 .43099 -0.22
76 .40898 -0.22
77 .38692 -0.22
78 .3648 -0.22
79 .34259 -0.23
80 .32028 -0.23
81 .29787 -0.23
82 .27531 -0.23
83 .25259 -0.23
84 .22969 -0.23
85 .20656 -0.23
86 .18316 -0.23
87 .15942 -0.24
88 .13523 -0.24
89 .11047 -0.24
90 .08486 -0.24
91 .05798 -0.24
92 Open .02713 -0.24
for each INCH of the radiator (and lumped coil)
A visual description would be a constant current to the coil, and then
a linear taper to the tip.
The corresponding launch characteristic:
1.80dBi @ 29°
By Decimating the lumped value across 10" (corresponding to the large
solenoid's apparent size ascertained from the photographs); to 10
lumped values of 4.28078µH (adjusted to re-obtain resonance); placed
at successive 1 inch segments (50..59); we find the following changes:
1 W2E1 1 0.00
2 1.0005 0.00
3 1.0011 -0.02
4 1.0017 -0.02
5 1.0024 -0.03
6 1.0031 -0.04
7 1.0039 -0.04
8 1.0047 -0.05
9 1.0054 -0.05
10 1.0063 -0.06
11 1.0071 -0.07
12 1.008 -0.07
13 1.0089 -0.08
14 1.0099 -0.08
15 1.0108 -0.09
16 1.0118 -0.09
17 1.0129 -0.10
18 1.014 -0.10
19 1.0151 -0.11
20 1.0162 -0.11
21 1.0174 -0.11
22 1.0187 -0.12
23 1.02 -0.12
24 1.0213 -0.13
25 1.0227 -0.13
26 1.0241 -0.13
27 1.0256 -0.14
28 1.0272 -0.14
29 1.0289 -0.14
30 1.0306 -0.15
31 1.0324 -0.15
32 1.0344 -0.15
33 1.0364 -0.16
34 1.0385 -0.16
35 1.0408 -0.16
36 1.0432 -0.17
37 1.0458 -0.17
38 1.0485 -0.17
39 1.0515 -0.17
40 1.0547 -0.18
41 1.0582 -0.18
42 1.0621 -0.18
43 1.0665 -0.18
44 1.0714 -0.18
45 1.0776 -0.19
46 1.0854 -0.19
47 1.0886 -0.19
48 1.0876 -0.19
49 1.083 -0.19
50 1.0748 -0.19
51 1.0633 -0.20
52 1.0484 -0.20
53 1.0301 -0.20
54 1.0084 -0.20
55 .98291 -0.20
56 .9533 -0.20
57 .92528 -0.20
58 .8983 -0.21
59 .87192 -0.21
60 .84597 -0.21
61 .82036 -0.21
62 .79502 -0.21
63 .7699 -0.21
64 .74494 -0.21
65 .72014 -0.22
66 .69545 -0.22
67 .67086 -0.22
68 .64635 -0.22
69 .62191 -0.22
70 .59751 -0.22
71 .57314 -0.22
72 .5488 -0.23
73 .52446 -0.23
74 .50012 -0.23
75 .47576 -0.23
76 .45136 -0.23
77 .42692 -0.23
78 .40243 -0.23
79 .37785 -0.24
80 .35318 -0.24
81 .32841 -0.24
82 .30348 -0.24
83 .2784 -0.24
84 .25312 -0.24
85 .22759 -0.24
86 .20178 -0.24
87 .1756 -0.25
88 .14894 -0.25
89 .12165 -0.25
90 .09344 -0.25
91 .06384 -0.25
92 Open .02987 -0.25
for each INCH of the radiator (and lumped coil)
A visual description would be a constant current to the coil, and then
a linear taper to the tip. It should be noted that for the protocol
of solenoid assembly by lumped parts, the current into the solenoid
does not equal the current out of the solenoid.
The corresponding launch characteristic:
1.56dBi @ 29°
Or roughly a quarter dB difference between the two (being generous, a
6% variation in absolute signal strength)
Any surprises? Perhaps to the easily surprised, but a quarter dB
variation hardly counts in the real world. Moment to moment
propagation variation will eclipse or boost this easily (although
employing 0.3dB to boost or eclipse is a strain on language). The
real world is going to suffer the bitch of matching R (being resonant
does not confer a 50 Ohm match to this small radiator). Does the
current drop through the solenoid? Again, no surprise. Does it drop
enough? Well that is arguable given the lack of attention to details
of specifying the original test.
Has any new precept been obtained that has not already been supplied?
Insofar as the complaint of not seeing the current variation goes,
that was answered long before the 350 itinerant postings that ignored
it. Does the decimation offer enough accuracy? Angel population
counts will undoubtedly be re-entered into with relish to make that
illusionary exploration despite the obvious variation of so little as
a quarter dB did for the first huge leap being the greatest difference
that will be found.
73's
Richard Clark, KB7QHC
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