At 07:04 AM 4/8/2004 -0700, you wrote:
>John,
>
>Thank you so much for the explanation. If I understand your email
>correctly the circuit should look something like the attached .bmp.
>
>R1=9K, R2=700
>(9000/700)+1=13.86
>
>Again, thanks for your help!
>
>Steve

The offset voltage is wrong and the resistor values are rather
low.

Try this instead (view in fixed-width font such as Courier):


                            Rs     +12
                           ___    |\|
                       o--|___|---|+\
                                  |  >------+---o
                                +-|-/       |
                                | |/|       |
                                |  ===      |
                           R1   |  GND      |
                           ___  |  ___      |
                     +12 -|___|-+-|___|-----+
                                |    R3
                               .-.
                               | |
                               | |
                            R2 '-'
                                |
                                |
                               ===
                               GND

Rs = 6K49
R1 = 182K + 1K00
R2 = 7K32
R3 = 88K7 + 1K78

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

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