# SimpleCalc

SimpleCalc is a small application that can help you calculate the cascaded noise figure of your EME receiving chain, predict the amount of sun noise your system should be able to detect and the SNR expected when receiving your own echoes or those from another station.

SimpleCalc can also be used to measure the level of noise received, it uses filtering on the audio signal from the radio (via soundcard) and presents the filtered data (RMS value) in a separate window.

During installation and debugging of my 70cm EME system, I developed SimpleCalc to help me understand and calculate the noise figure of my system, the effects of changing LNA's, cable losses etc. I also needed a quick and easy tool to help me calculate the expected sun noise I should be able to measure and at the same time, provide an easy way of recording notes taken during measurements and experimentation.

For many many years, the "EMECalc" program by Doug VK3UM (sadly now a Silent Key) has been "The tool" to use for doing this and much more (and still very much is!).

In my case, I needed something a little more "light" with only a fraction of the features of EMECalc. I also wanted to learn something!

This was how SimpleCalc was born.

Quick jump to sections:

Main window

SFU handling and update

Two station performance and echoes window

Noise measure window

Comment editor window

Calculation theory

Calculation of RX noise figure

Calculation of system noise figure

Calculation of figure of merit, M (G/T)

Calculation of expected Y-Sun level

Usage of "crosscheck" feature

Calculation of own echoes

Calculation of DX station echoes

Download section

Release notes

DISCLAIMER:

I'm NOT an mathematician !!

I have tried to make SimpleCalc correct. However, I do not by any means, claim to have the full overview of all the aspects of the math going into making the calculations "super precise". SimpleCalc calculates NF, predicts sun noise, and calculates echo strengths but leaves out a few of the finer details, details that might get you 0.1 or 0.2 dB closer to "the real truth".

That being said, I think (and hope) that the application makes up for this by being simple and easy(er) to use.

One thing you can be absolutely sure about, is that there are errors in the program :) When you find some, please send me an email of what you see and have done. My email address is on the CV/Contact page.

During the development and testing of SimpleCalc, I got valuable input and suggestions from members of the Moon-Net email reflector, especially from Vladimir UR5EAZ, for which I'm very thankful!