Fig. 1. The Mini-Supply,
Fig. 2, Mounting the ten watt zener diodes.
circuit and replace it with a 20K pot in series with a 5600 ohm resistor. Tin's combination would pretty nearly meet the requirements, but being economical at heart, why not use the 25K pot in series with a value ot resistance which provides the same voltage ratio? Using the measured value of resistance (5600 ohms), the correct value of series resistance may 1 >e calculated by the following procedure:
Calculate the ratio designated K) of the measured resistance (Rm) to the total resistance in the voltage divider (Rt), In this case the total resistance consists of the 10K resistor in series with the 25K pot or, Rt = 35000 ohms. Therefore
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