## PSN-L Email List Message

Subject:
From: "Ted Blank/Santa Teresa/IBM" ted@..........
Date: Fri, 18 Aug 2000 07:47:02 -0400

```Murray,

Another way to achieve your goal is to change the amplification (or let the
user do it).  By changing the vertical scale on the display or the
amplification of the signal you could achieve the effect described by the
previous notes.  For example, you could have a multi-position switch
labeled M1, M2, M3, M4 etc.  Going up the scale with the switch would
reduce the amplification of the signal by the appropriate amount (through
judicious choice of resistors).

The vertical scale would stay the same on the screen, but it would get
progressively more difficult to make the signal reach the same amplitude at
higher "M" values.  In essence you simulate the logarithmic Richter scale
by making the person jump 10 times harder for a longer time to drive the
display to the top and bottom for each increment.  The user would choose
their M value and start jumping.  Arrange things so it was very easy to
generate a M1, reasonably easy for M2, etc.

The difficult thing will be getting people to read the instructions and try
it twice or three times to see the difference.  Most people will just jump
up and down and say "neat" and walk away.  YOu might find that more people
get educated if you do small group demonstrations - you know, "next quake
in 10 minutes".  Pick a person in the audience.  You explain the
differences in the Richter scale in once sentence (more than this and they
will walk away).  Then you have the person jump up and down and make the M1
(easy).  Switch to M2 and get them jumping.  If you get the crowd involved
("Come on everybody, cheer Jimmy on!")  you'll have everyone notice how
much harder Jimmy has to work for each Richter increment.

If Jimmy runs out of steam, maybe you could ask 9 other people to come up
and help.  THat would be  a great visual display of the logarithmic nature,
since you can then explain "Sorry, I don't have room up here for another 90
of you to join in - plus the stage would collapse."  Should take about 4-5
minutes and every would have a good time and remember the message.  I think
you'll be disappointed if you just expect people passing by to conduct the
experiment themselves - they probably won't bother.  Don't forget to use a
large screen.

Regards,
Ted Blank

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