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#1
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![]() "Dr. Slick" wrote in message om... Someone else suggested that i place the meter right at the cantenna, to at least exclude the patch from meter to dummy load. No, you don't want to do that. Put as much loss as you can between the meter and the Cantenna. 100 feet of RG58 will have about 6.5 db of loss. It will make your load a lot closer to 50 Ohms. There are Tables that show SWR as a function of cable loss for a given mismatch. One chart that I have in "Reference Data for Radio Engineers" shows that with a load SWR of 1.4, and 6.5 db of cable loss, the SWR at the driving end is around 1.075. Note that you DO NOT want low loss coax. Tam/WB2TT |
#2
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"Tarmo Tammaru" wrote in message ...
"Dr. Slick" wrote in message om... Someone else suggested that i place the meter right at the cantenna, to at least exclude the patch from meter to dummy load. No, you don't want to do that. Put as much loss as you can between the meter and the Cantenna. 100 feet of RG58 will have about 6.5 db of loss. It will make your load a lot closer to 50 Ohms. There are Tables that show SWR as a function of cable loss for a given mismatch. One chart that I have in "Reference Data for Radio Engineers" shows that with a load SWR of 1.4, and 6.5 db of cable loss, the SWR at the driving end is around 1.075. Note that you DO NOT want low loss coax. Tam/WB2TT Perhaps you are correct. That you would only want to use the meter right at the load if you wanted to measure the real SWR of the antenna, as the coax loss will improve the return loss (SWR). I'll try a long piece of RG-58 and see how the incident power is affected. Slick |
#3
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That would give you 13db of return loss which would be an SWR less than 2:1
even if the far end was a dead short. Given his current SWR I woud say this would result in a return loss of around 30db. Numbers are a lot of by guess and by golly but think I am not too far off. "Tarmo Tammaru" wrote in message ... "Dr. Slick" wrote in message om... Someone else suggested that i place the meter right at the cantenna, to at least exclude the patch from meter to dummy load. No, you don't want to do that. Put as much loss as you can between the meter and the Cantenna. 100 feet of RG58 will have about 6.5 db of loss. It will make your load a lot closer to 50 Ohms. There are Tables that show SWR as a function of cable loss for a given mismatch. One chart that I have in "Reference Data for Radio Engineers" shows that with a load SWR of 1.4, and 6.5 db of cable loss, the SWR at the driving end is around 1.075. Note that you DO NOT want low loss coax. Tam/WB2TT |
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