Specification
Below are the computer calculations that were instrumental in developing the G4TPH Mag-loops
Using a computer program helped in understanding various aspects of how magnetic loops operate.
ML-40 |
Loop Calculations |
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Description |
40m |
30m |
20m |
Loop diameter(m) |
1.550 |
1.550 |
1.550 |
Conductor length(m) |
4.869 |
4.869 |
4.869 |
Conductor diameter(mm) |
10 |
10 |
10 |
Frequency(MHz) |
7.05 |
12.20 |
14.20 |
Power(W) |
15 |
15 |
15 |
Efficiency% |
24.03 |
68.32 |
78.58 |
Efficiency dB |
-6.19 |
-1.65 |
-1.05 |
Bandwidth kHz |
9.05 |
28.56 |
45.58 |
ML-20 |
Loop Calculations |
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Description |
20m |
18m |
15m |
12m |
10m |
Loop diameter(m) |
1.050 |
1.050 |
1.050 |
1.050 |
1.050 |
Conductor length(m) |
3.299 |
3.299 |
3.299 |
3.299 |
3.299 |
Conductor diameter(mm) |
10 |
10 |
10 |
10 |
10 |
Frequency(MHz) |
14.20 |
18.10 |
21.20 |
24.20 |
28.50 |
Power(W) |
15 |
15 |
15 |
15 |
15 |
Efficiency% |
53.28 |
72.73 |
82.26 |
88.05 |
92.89 |
Efficiency dB |
-2.73 |
-1.38 |
-0.85 |
-0.55 |
-0.32 |
Bandwidth kHz |
22.62 |
43.74 |
72.78 |
115.44 |
210.51 |
The above are theoretical specifications based on computer modelling. I do not claim that the ML-40 and ML-20 will perform to these specifications. The antennas were based on these calculations however the antennas in practice may perform better or worse than indicated by the above calculation. However in my operating I am always amazed at the contacts I am able to make using the ML-40 and the ML-20 Mag-Loops.
See the G4TPH Mag-loop in February's Practical wireless magazine