Good Day,
interesting thought on the 50% FSD, David - thanks.
R&S has a long history of scales that go a tad over the ?usual¡® FS display. See for example their?more popular type UVM microvolt meter, which they have released over several series¡ This can have some practical?advantages?when working with adjustable?signal sources?for example; i.e. less switching is needed.?
Cheers,
Magnus?
On Sun, Aug 21, 2022 at 12:10 PM, magnustoelle wrote:
Or Rohde & Schwarz, may I add ?
?
Cheers,?
?
Magnus?
Although the scales are marked 3.0 and 10 on the R&S instrument, I note that the full-scale on the 3 V range is 3.2 V. It looks to me as if the 10 aligns with sqrt(10)=3.16. I think if you assume your inputs are randomly distributed, you can't beat that if there is only one other scale between 1 and 10.
To keep a reading at least 50% of full scale, I think one wants FSDs of
1, 1.77828, 3.16228, 5.62341 and 10.
Perhaps calling them 1, 2, 3, 5 and 10 would not be too bad. Just ensure the 3 V scale can actually read up to 3.1622 and the 5 V scale up to 5.62341
I like the idea someone had earlier of offsetting the scale, so the left does not read zero. That would actually be quite neat for my application (Q-meter), because one wants to peak up on something carefully. I will probably drive the meter from a DAC, because I can use a computer to flatten the frequency response, so it does not matter if the output power of the oscillator, or sensitivity of the detector changes with frequency.
I don't know if there's any real advantage in moving coil meter, compared to a decent analogue scale on a digital display. I don't mean a bar-graph with 10 segments, but implement something where there's at least 400 pixels across.
