ANTENNAS FOR 100 POUND DXPEDITIONS
Figure 71 Measuring Traveler coils with Photoshop The measurements and final inductances after experimental modeling appear below. As you can see, these values were about as close as those measured directly on the Force-12 Sigma5. And, all this was from just a picture! Measured in antenna
Guess
Determined by modeling
Name
Diameter
Number of turns
Length
XL
Total XL
Actual XL
10m
0.85
2
0.2
0.12
0.12
0.28
12m
0.65
3
0.3
0.16
0.28
0.58
15m
0.75
4
0.3
0.35
0.64
1.10
17m
0.75
5
0.52
0.41
1.05
1.75
20m
0.7
8
0.83
0.68
1.73
3.25 + 1 pF
Table 2 TW Antenna Traveler coil values
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