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Bazz4CQJ · 19th Feb 2018, 6:30 pm

But, isn't the quest for a high-impedance millivoltmeter driven by the desire not to load low-level circuits under test? So, even thought you could do number crunching and try get a figure with the power meter, the better approach there would probably be a probe which does not significantly affect the circuit. Of course, you'd still have the option to switch between the power meter at Z=50, or the voltmeter at Z>>>50. Side-steps the great unknown of what 'magic' diodes to use for sensitive RF probes...perhaps?

B

19th Feb 2018, 6:30 pm	#4
Bazz4CQJ Dekatron Join Date: Apr 2009 Location: Oxfordshire, UK. Posts: 4,934	Re: W7ZOI power meter (AD8307 based) But, isn't the quest for a high-impedance millivoltmeter driven by the desire not to load low-level circuits under test? So, even thought you could do number crunching and try get a figure with the power meter, the better approach there would probably be a probe which does not significantly affect the circuit. Of course, you'd still have the option to switch between the power meter at Z=50, or the voltmeter at Z>>>50. Side-steps the great unknown of what 'magic' diodes to use for sensitive RF probes...perhaps? B __________________ Saturn V had 6 million pounds of fuel. It would take thirty thousand strong men to lift it an inch.