AnsweredAssumed Answered

HP 438A zero set specification

Question asked by Rune on Apr 30, 2008
Latest reply on May 2, 2008 by RayH
Hello!

I have a problem with reading the specifications on 438A power meter

The zero set spec. is "+/- 0,5% of full scale on most sensitive range. Decrease percentage by factor of 10 for each higher range +/- 1 count." I am a little confused with the +/- 1 count is this the resolution of the meter?
i.e. at 1 mW range 3 (auto filter) will the worst deviation be 0,005% of 1 mW multiplied with the resolution 0,001 mW equals 0,00105 mW?

When calculating the uncertainty of the measurement will the resolution of the meter be a separate component or is this already included with the +/- 1 count specification on the zero set?

Thanks!

Outcomes