Herein you will find a single Microsoft Excel Spreadsheet in Microsoft Office 1007 format (.XLSX.)

The file has been virus scanned for your convenience and can be downloaded by clicking this.

Some of the calculations you will find in the spreadsheet are:

  • Rectangular Impedance to its Polar Form
  • Admittance to Impedance in Polar Form
  • Admittance to Impedance in Rectangular Form
  • Impedance of an RL to Polar Form
  • Capacitive Reactance, XC
  • Inductive Reactance, XL
  • Power Factor for Specific Phase Angle
  • Effective Radiated Power (ERP)
  • Real Power, PREAL
  • Peak Envelop Power (PEP)
  • Time Constants in RC Networks
  • Parallel and Series Resistances
  • Determining L with a specific F and C
  • Q
  • AL Values for Ferrite Cores
  • Free Space Single Layer Inductor
  • Deviation Ratio and Modulation Factor
  • Calculating Frequency for a 555 Timer
  • Bias Resistor for LEDs
  • Voltage Gain of Differential Amps
  • ... and many others.

If you would like this in an earlier format please request it via the e-mail address found on the "Contacts" page of this web site. Put "Your Web Site - Amateur Radio Calculations" in the subject of your e-mail or it will not be seen. Please note that some of the coloring and fancier capabilities will not be present in the MSO 2003 version.

The spreadsheet found here has a few conversions built in. If you are looking for an exceptional tool for converting just about any measurement to another measurement you should visit Josh Madison's web site. Here's a LINK to get you there quickly. You'll want to download "Convert for Windows." It's Free!

I think I will take all the calculations in the Excel spreadsheet and convert them to Javascript instead... maybe I will do that this winter. Hmmm.

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Picture In the mean time, I've noticed the spreadsheet doesn't include a common calculation - voltage divider. Please take a look at Figure 1. Voltage dividers can help you create reference voltages for other circuits; e.g., using a voltage comparator (LM339, Quad Voltage Comparator). As seen in the schematic our source voltage is 12VDC. Let's say, for this example, that we need 6.8VDC at Output B. Here's what you do.

First, select a reasonable total resistance. Since we're using an Comparator, which have very high input impedances they require very little current so we'll use 10KΩ for R1 and R2 combined. Now, divide 10,000 by 12; e.g, 10,000 ÷ 12 = 833.33Ω. This is how many ohms per volt exist in this circuit. Now, multiply 833.33 by 6.8 (our required voltage); e.g. 833.33 x 6.8 = 5,666.66Ω. The resistance for R2 = 5,666.66Ω. Then, subtract that answer from 10,000Ω. Here we get 4,333.33Ω for R1.

Place the larger resistance on the side of the circuit where the greatest voltage exists. Let me say it like this. Since 6.8 is further from ground than it is from 12VDC it gets the most resistance. Since our resistance values are ~4.3KΩ and ~5.6KΩ the larger resistance is applied to R2; e.g., R2 = ~5.6KΩ. You can use variable resistors for R1 and R2 so you can dial them in or you can use multiple fixed resistors for R1 and R2 where the total resistance for R1's and R2's set of resistors equal close to 4,333Ω and 5,666Ω, respectively.


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