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Hi Dan,
?? In the "Loads (R+JX)" window, you enter a desired position on a particular wire number, and the value of the load, which presumably would be a coil or a capacitor. It will tell you where the load actually got put on the wire, as it must be in the middle of a segment. You can adjust the number of segments to put the load closer to where you want, if it didn't come out close enough the first time. A good way to verify that the load is doing something is to change the value of the load and look at what happens to the feedpoint impedance, which you can see in the "Src Dat" (Source Data) window. For example, if you start with a 10.3 meter vertical, 40mm diameter, 11 segments, over perfect ground, with the feedpoint (source) at the middle of the lowest segment, you should find that a coil of 0+j582 ohms gives you very close to resonance: close to zero imaginary component in the feedpoint impedance. Raising the coil reactance causes the feedpoint to become inductive: positive imaginary component. And lowering it causes the feedpoint to become capacitive. Cheers, Tom |
#2
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Let me make sure I understand. First I used the LCR configuration, that should
not make a difference? Are you saying a load is placed in the middle of a segment? If I wanted to create a center loaded vertical one way would be to create a 1 wire antenna and place the load in the middle? Is that correct? Thanks, Dan K7ITM wrote: Hi Dan, ?? In the "Loads (R+JX)" window, you enter a desired position on a particular wire number, and the value of the load, which presumably would be a coil or a capacitor. It will tell you where the load actually got put on the wire, as it must be in the middle of a segment. You can adjust the number of segments to put the load closer to where you want, if it didn't come out close enough the first time. A good way to verify that the load is doing something is to change the value of the load and look at what happens to the feedpoint impedance, which you can see in the "Src Dat" (Source Data) window. For example, if you start with a 10.3 meter vertical, 40mm diameter, 11 segments, over perfect ground, with the feedpoint (source) at the middle of the lowest segment, you should find that a coil of 0+j582 ohms gives you very close to resonance: close to zero imaginary component in the feedpoint impedance. Raising the coil reactance causes the feedpoint to become inductive: positive imaginary component. And lowering it causes the feedpoint to become capacitive. Cheers, Tom |
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