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Precision Resistor Calculator

Select a Precision Resistor From Combinations of Standard Resistors.

I had been repairing some older VTVMs and found that I needed to replace a couple of the precision resistors in the range switches. Some of these must've been custom ordered for the production of these VTVMs because I couldn't find them anywhere as a stock item.

I found some very close matches calculating by hand, but I wish I had something like this to use. This script does an exhaustive search of your chosen range (pick a range you may have available to you) and will attempt to find the best matches of TWO resistor in series of parallel.

For more technical data, see: logwell.com

  • E6 - 20% tolerance, consisting of 6 values in each decade of: 1, 1.5, 2.2, 3.3, 4.7, 6.8
  • E12 - 10% tolerance, consisting of 12 values in each decade of: 1, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9, 4.7, 5.6, 6.8, 8.2
  • E24 - 5% tolerance, consisting of 24 values in each decade of: 1, 1.1, 1.2, 1.3, 1.5, 1.6, 1.8, 2.0, 2.2, 2.4, 2.7, 3.0, 3.3, 3.6, 3.9, 4.3, 4.7, 5.1, 5.6, 6.2, 6.8, 7.5, 8.2, 9.1
  • E48 - 2% tolerance, consisting of 48 values in each decade of: 1.00 to 9.53
  • E96 - 1% tolerance, consisting of 96 values in each decade from 1.00 to 9.76