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DO YOU EXCEL IN ELECTRONICS?

Part 3: The Bottom Line
by Aubrey Kagan

Start ý Calculating The Odds ý Strange Occurrences ý Can You Relate? ý Nothing Up My Sleeve ý Source and PDF

STRANGE OCCURRENCES

It may have occurred to you that you can only use standard resistor values, that the ratio of standard values from R1 to R2 may not result in a close enough reference voltage, and that there may be a better ratio using standard values. A formula cannot be used as a variable cell in the Solver function, so I used RE1, RE2, and RE3 as the variable cells, created three new cells with the nearest standard resistors (from the NearestValueB function), and then used these values in the calculation of V_ka.

Unfortunately, the Solver function only generates small changes in the variable cell and the NearestValueB function completely obliterates the effect by finding a standard value. The Solver function quickly assumes that there is no possible optimization because a small change in the variable results in no change in the target cell. As it stands, until I can find a way to get the Solver function to increment a cell by a number greater than unity, I donýt believe Iýll be able to resolve (pun unintended) this issue.

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