[Elecraft] Radio Shack ESD mat doesn't meet spec

[Rich]

I have concerns about how that resistance was determined.  I do not think the
methodology provides an accurate result.
First, look at eh schematic of the 260 - there are components in series
/parallel with the meter. Even with just the low current jack, there are
still components in series. 
Second, I have never, NEVER, seen an analog meter provide accurate reading
of a peak or transient voltage. The frequency response/ transient response
is not there. Some of the components in parallel with the meter movement are
there to protect the meter. Additionally, there are balanced weights on the
mechanical portion of the movement to "stabilize" the movement and thus
decrease transient response. 
When trying to calibrate a synchro system that was providing a sine wave of
about 20 Hz, my Simpson (freshly calibrated) was off by more than 20 %. of
the voltage displayed on an Oscilloscope which I was using for making the
adjustment. 
Third, I know of no Simpson 260 that has a lowest range of 60 micro-amps,
everyone I know of is either 100 or 50 micro-amps. Don't knew what the new
ones are, but am sure that none of the old big ones have that value.
Here is a source for some info on the various Simpson meters. 
http://simpson260.com/downloads/downloads.htm

Rich

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