Here are some quick pointers to getting the best out of the K6TU.NET Propagation as a Service web site.
The Essentials 1 – Station Configurations
THE key to getting accurate propagation predictions is to describe the configuration of the TRANSMIT and RECEIVE stations using either a Station Configuration or Advanced Station Configuration. Although K6TU.NET provides a number of pre-defined configurations like “TriBander & Wires”, its is worth taking a few quick minutes to construct your own configuration especially for the TRANSMIT configuration.
The TRANSMIT configuration describes the antenna and transmit power used for each band. For most predictions, this is a description of your station. Power is easy – its the Transmitter power in Watts you will be using – for example, in a low power contest this might be 100 watts. For a high power contest for a US operator with an legal limit amplifier, 1500 watts would be the choice.
For the antenna, K6TU.NET provides a wide range of antenna options from Vertical to large Yagi antennas at a variety of tower heights.
The RECEIVE configuration should describe the Antennas for the stations you expect to work. Although you may be constrained by local limitations such as Home Owner Associations to a Vertical antenna or a stealth dipole, many of the hams you will work on the bands don’t have these issues. Picking a configuration such as Vertical/Dipole is going to give you a VERY PESSIMISTIC prediction – the key is to chose a configuration that is a reasonable assumption about the antennas the “other guy” is using.
For regular everyday operations, TriBander & Wires is a good starting point for the receive configuration. For a contest you can assume that most of the stations you will work are in the ‘serious contester’ category – in this case, ‘Serious Contester’ would be a better match.
The most common mistake I see new users to K6TU.NET make, is selecting Vertical/Dipole for BOTH transmit and receive station configurations.
The Essentials 2 – Solar Parameter
The Solar Parameter is the SMOOTHED SUNSPOT NUMBER to be used for the model ionosphere that is at the core of every propagation prediction.
You are likely familiar with Sunspot Numbers or the Solar Flux Index (SFI). NOAA has a good (and brief!) description of Sunspot Numbers and SFI which you can find at the following links: at
https://www.ngdc.noaa.gov/stp/iono/sunspot.html
https://www.swpc.noaa.gov/phenomena/f107-cm-radio-emissions
It is CRITICAL to understand that NEITHER of these are the Smoothed Sunspot Number which is a 12 month smoothed relative number calculated from the daily sunspot numbers. The Sunspot link above includes the formula that is used.
R12 is forecast for the future by the Royal Observatory in Belgium. K6TU.NET will automatically enter the current forecast value based on the month and year you specify for the prediction. This forecast is updated monthly and covers the forward 12 months.
Using either the Daily Sunspot Number or the Solar Flux Index will result in a meaningless prediction.
When specifying the parameters for a prediction, you can:
- Leave the default value of -1 which will lookup the value of R12 (both for past and future month, year combinations) as published by the Royal Observatory.
- Use the SSN Equivalent number as published by NorthWest Research Associates at their web site. SSNe is a number calculated from the ionospheric foF2 measurements over the past 24 hours. It is the value that when input into the propagation prediction model results in the same foF2 numbers as have been measured. Using SSNe provides the best “nearest” estimate of predictions over the next couple of days.