Owners of satellite dishes will sooner or later come across a concept such as "solar interference". This usually happens in the first year of operation of the antenna, when the provider itself warns users about the possibility of signal loss for this very reason. Let's figure out what it is and why radio transmission is deteriorating or completely disappearing.
What is solar interference?
Any star, including our Sun, emits not only visible light energy, but also centimeter-wave radio waves. When the sun is in a straight line with the satellite and satellite TV antennas, signal reception is not possible. All due to the fact that the Sun creates interference, and the signals of the transponder are banally blocked by noise from the Sun.
When does this happen
This phenomenon occurs 2 times a year - in autumn and spring. It is during these seasons that solar interference can be observed. Most often, this phenomenon occurs within 3.5 weeks from the days of the spring and autumn equinox. At this time, the Sun makes the annual path, crossing the equatorial plane.
In February and March, the interference first affects the earth stations located in the northern latitudes, then it covers the more southern receiving stations. At the equator, the peak of this phenomenon falls on September 21 (equinox). Then the zone moves to the southern hemisphere. It is the southern receiving stations that are the last to experience the influence of solar interference, which ends 3.5 weeks after the spring equinox.
The opposite is true for August, September, October, because the Sun begins to move in the opposite direction - to the Southern Hemisphere from the Northern. During this period, for each station, the interference period lasts for one week. Every day during this time, interference is affected. Moreover, in the morning, eastern communications satellites are influenced, in the evening - western ones.
How is this manifested?
At first, with a weak effect, weak noises may appear on the TV screen, which become strong during the day. At the very peak of solar interference, there is no satellite signal at all. Therefore, do not worry about this and think that you have something broken or the antenna has stepped aside. Everything is all right with you, and this phenomenon is completely normal.
What to do
At the peak of the signal, in the middle of a sunny day, it is advisable to withdraw the antenna from the satellite line in general. This is done so that the plastic parts of the irradiators do not melt. This can lead to a complete breakdown of the electronics of the converters. Because of this, aluminum reflectors very "successfully" concentrate the sun's rays at the focal point.
So if strong interference is detected or if the signal from the satellite is completely lost, check with your provider if solar interference has occurred or the signal is lost for another reason. If this is interference, then go up to the roof (or where your antenna is installed) and take it to the side. And then let her have to re-direct it to the satellite. This is better than spending money on new electronics converters. Although there are simpler ways. For example, you can simply cover the antenna with something opaque that does not let in sunlight.
The harm of solar interference
First of all, due to solar interference, radio stations and television companies that relay the signal from the satellite to the air suffer. As a result of this phenomenon, they lose the signal, which is fraught with marriage on the air and loss of rating. Therefore, all self-respecting companies prepare alternative signal sources and switch to them before the solar interference fully takes effect.
Also affected are stations that receive radio signals from the Express and Horizon satellites. A feature of these satellites is the movement in an inclined orbit. To receive the signal, Pansat XR4600D, Drake ESR-700 and ESR2000XT-plus receivers are used. As a result of interference, these receivers can “lose” satellites and begin tracking the sun. Therefore, you have to pre-program the receivers on these satellites as stationary and turn off tracking when a similar phenomenon occurs. When the interference passes, the receivers must again be programmed into these satellites as satellites with inclined orbits. All these actions need to be done 2 times a year, and this is an unnecessary effort. However, if the receiver receiver is not used, then you can simply transfer it to Stanby mode for the duration of solar interference.
Last but not least, stations receiving signals from the Express and Horizon satellites with inclined orbits suffer. Sometimes, during the interference, the data of the tracking tables may be checked. If at this time the controller is pointing to the Sun, then this will ruin the entire row of the table. As a result of repeated disruption of signal reception, one cannot avoid even if the interference is already over on the second day. Therefore, the controller is disconnected from the network in advance and after restoration of normal reception conditions it is turned on again. The main thing is not to miss this moment.
Ordinary users who use large diameter antennas may also suffer. In clear weather, the sun's rays are focused on the converter using this same antenna. The converter heats up and can melt. So it will fail, and the user will have to replace it with a new one. Therefore, watch out for solar interference and when it occurs, either take the antenna to the side or cover it with cardboard or an opaque film. Otherwise, the radiation of the sun using the antenna will melt the receivers.
Determination of interference time
There are special programs for determining the time of the onset of solar interference. One of them is called Look, and it is distributed free of charge on the Web. The program is simple and even primitive, it just shows the exact date when the interference will be maximum. Also, with its help, you can find out the first and last days of the "session" of interference. To do this, from the specified date you need to count the number of days ago and forward. The number of these days is also determined by the program depending on the indicated diameter and range of the antenna. But it is worth noting that this program only works with receiving stations in the Northern Hemisphere.
If you did not find or do not want to download the above program, then you can use the online calculator. It is available on the PanAmSat website. However, to work with it you need to have some data.
For example, you need to know the satellite’s orbital position (you can select it from the search or enter it manually), the coordinates of the receiving station (you can select your city from the list), frequency range, antenna diameter, season. If you have all this data, you need to enter it into the online calculator and click "Calculate". The program will show the start and end time of the interference. All data will be indicated in HTML format, so you can print it and hang it on the wall to always remember this.
Features of working with a calculator
Note that although this program is focused more on the United States, it works for all receiving stations. However, there are some features of working with this program:
- When entering the diameter of the antenna, you need to enter values with decimal places using a period, not a comma. Otherwise, the program will freeze and will not be able to calculate anything.
- Satellite positions are indicated in degrees of west longitude from 0 to 360 W (west of the Greenwich meridian). Therefore, for satellites in the Eastern Hemisphere, you need to enter values with a minus sign.
- Also do not get confused in the dates. In the US they write the date like this: "month-day-year." We are used to indicate the date like this: "day-month-year."
Usually this calculator is enough to accurately calculate the occurrence of interference and its end. But if you can’t figure it out, then visit the thematic forums on satellite television. There are usually topics for determining interference for different cities. Moreover, some providers warn users about the onset of this period and even give tips on how to "survive" it correctly.