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VK3UM downloads

Doug VK3UM was a friend from our days at Unley High School during the mid 1950s, a common interest was that of radio and electronics leading to our introduction to ham radio through the 288MHz band (now no longer part of Australian allocations).

When he died of a massive stroke on 22 February 2016 I promised myself that his wonderful work writing programs for our hobby would not be lost. For the moment and until the Wireless Institute of Australia puts the programs into safe storage, I have put them here on my website. This is with the approval of his wife Bev.

EME Calculator [EMECalc]

This software, with the addition of a simple level indicator and preferably an in-line switched attenuator, will provide a most accurate way of assessing your equipment’s performance.

This software will accurately predict *, to a very high degree;

        the level of your own Moon echoes

        the level of Echoes you will receive from another Station

        the level of Echoes the other Station will receive from you

        the level of Sun Noise you and the other Station will receive.

        the level of Moon Noise you and the other Station will receive and

        the level of received Galactic Noise you will expect to receive with combinations of Sources.

In addition a "How to .." section has been provided to enable you to select the best dish feed type combination as well as answering the vexing question of "if I increase the size of my existing Dish " will it be worth while?

Download EMECalc

The VK3UM EME Planner

The VK3UM Planner is just that, an EME Planner, and  supports the following functions (and many more).

Download EMEPlanner

VK3UM Libration Calculator. [LibCalc]

This software was inspired by Charlie Suckling (G3WDG) article in DUBUS 3/2010 and with his help and suggestions has been the basis of this program. My thanks also go to Barry VE4MA, Al W5LUA, Dave G4RGK and John VK5DJ who have assisted with the beta testing and provided valuable suggestions for improvement.

Download Libration Calculator

VK3UM Electro Magnetic Radiation Calculator  (EMRCalc)

(also now known as Electro Magnetic Emission.. a more public friendly name !)

Download EMRCalc

Atmosphere Absorption Attenuation [Atmosphere]

[Attenuation by Atmospheric Gasses]

Electromagnetic waves are absorbed in the atmosphere according to wavelength. Two compounds are responsible for the majority of signal absorption, Oxygen (O2) and water vapour (H2O).

The first peak occurs at 22 GHz due to water vapour, and the second at 63 GHz due to oxygen. The actual amount of water vapour and Oxygen in the atmosphere normally declines with an increase in altitude because of the decrease in pressure.

Total attenuation through the atmosphere at any frequency, through unobstructed atmosphere, is the sum of free space path loss, attenuation caused by oxygen absorption, and attenuation caused by water vapour absorption. Rain attenuation, when present adds an additional element.

Total path attenuation = Attenuation Free Space Path Loss + Attenuation caused by Oxygen + Attenuation due to Water Vapour + Attenuation due to Rain + Fog and Cloud Attenuation.

This program [Atmosphere] calculates the absorption attenuation at Microwave frequencies for both terrestrial and slant paths for Amateur frequencies from 10-241 GHz.

The calculations applied in this program are based upon the International Telecommunication Union (ITU) recommended methods as listed in the Reference section of this Document.

The program has been written primly as a supplement to my EME Calculator Program  to refine overall loss calculations for frequencies above 10GHz where these factors become a significant.

Download Atmosphere



In my other software programs , EMECalc and EME Planner, provision has been made to provide a Real Time Display of the locations of both Quiet and Noise Sources.

For those wishing to make subjective measurements and check receive performance, it would be beneficial to know the positions of the Sources in advance so the most appropriate time can be chosen commensurate to the availability and position of the Sources.

Hence the VK3UM Noise Source Planner was borne!

This software will provide (similar to the EME Planner) the ability to select the start and end dates of  when you wish to make observations as well as the calculation increment desired.

The Noise Source Planner also provides a Real Time Display of all Sources which include :

For those that use a Polar Mount this may be selected as well as the conventional Azimuth / Elevation Display.

The facility for printing your calculation (in landscape) is also provided.

Enter your Home Data and then Save. The program also saves your Calculation and Display mode chosen as default.

Download NoiseSources

VK3UM 4 Stage Inter Digital Filter Design [IDF]

Simply change any of the parameters and the software will recalculate and present the new design commensurate to your requirements. It may also be extended beyond 4 stages by using the internal stage dimensions.

Suitable for frequency ranges from 300 MHz to 10 GHz.

** Note it can be expanded to ‘n’ poles by using inner pole dimensions

Download IDF

Transmission Impedance Calculator

Download Impedance Calculator Help File

Download Impedance Calculator

VK3UM AUTO TRACK [Autotrack.exe]

This Program has been developed as a Computer interface for the VK5DJ Auto Tracking hardware only.

The display and format has been re-created in a Windows format along the same colour lines and features provided in the original DOS VK3UM Auto Tracking program that was first developed in 1984 and used in conjunction with the VK3UM tracking board.

Download Autotrack