I know I'm going to regret stepping into this one, but since when has that stopped me before...
> Thanks, Gary, for admitting the 43 doesn't measure power > directly. What do you mean by "measure power directly"? If you're talking about comparing a thruline measurement against absorptive/calorimetric techniques, then that's apples and oranges, one is measuring power in a transmission line (either with or without reflections present), the other is measuring power absorbed into a load, big difference. Please clarify what you mean by "measuring power directly" so at least we're all on the same page. > Of course, it is a directional coupler, no argument. That > makes it a reflectometer No, it's not a reflectometer, it can't do forward and reverse measurements concurrently. > If the meter did as you suggest, then it would show what the > voltage and current are at any point in the line, and > therefore be able to tell you what the impedance is at that > point Not without knowing the phase between the two it couldn't. > BTW, my POS Daiwa can show me a 100% reflected condition, > just like the Bird. And just like the Bird, it doesn't > indicate if that's an open or a short. A Bird isn't a VSWR bridge, it's a directional wattmeter. Yes, it can be used in a roundabout way to measure/calculate VSWR, but it's not a "VSWR meter". Sidebar. I grit my teeth when I hear someone on the radio say "my SWR meter shows I'm putting out 100 watts". Since when does a SWR meter measure power!???! Do you use your bathroom scale to check your blood pressure? Egads. I'm not taking a stance here (at least not yet) on the relative merits of the Bird 43 or other thruline-type wattmeter line sections or elements, I'm just trying to get a handle on the matter that is the subject of debate... --- Jeff WN3A