PROPAGATION   BEACON

   

VA2MGL 

 

 


10 meter                         6 meter

          28,196 Mhz            50,0155 – 50,038 Mhz

 

 

 

VA2MGL Beacons’s site

 

 

Transmitters and equipments  in the Beacon shelter

 

 

28,196 mhz VA2MGL/BCN  page

50,0155 mhz VA2MGL/B2  page

50,038 mhz VA2MGL/B3  page

            The purpose of the Propagation Beacons

            A good listening report

            The wave propagation for 6 and 10 meters band

            Interesting hamradio links

            To contact me

            Thanks to

The purpose of the Propagation Beacons

The purpose of the listening to and identifiyng of radio beacons is to know the propagation quality of radio waves, and thus, to determine which continent can be joined or favored at a given moment. There are radio beacons on most hamradio wavebands and even on certain frequencies outside hamradio bands.

CW mode is recommended for being easier to copy  when signals are weak. The message passed on with beacons is generally the callsign, QTH, as well as the power and the antenna used.

The prediction of  wave propagation is by way of the always vague being ionosphere being often unreliable, the only way of making sure that a band is opened or adequate to support radio contacts is by  listening to radio beacons. The six and ten meters bands are especially unpredictable, being subject to several kinds of different propagations, and also often on the edge of the MUF, or highest useful frequency.

On the band of ten meters (28 mhz), there are about 180 propagation beacons in operation between 28.175 mhz and 28.300 mhz, while there are two hundred more of them on the six meter band, mainly between 50.000 mhz and 50.100 mhz. These radio beacons are spread worldwide.  

By the listening to these, one sometimes can deduct the distance and the number of hop made by the wave, as well as the area of the ionosphere able to reflect our transmissions. One will frequently be able to deduct even the kind of propagation, according to the QTH of the station heard, the time and the season. Wave propagation of this kind of transmission is made by reflection on various layers of the ionosphere with a one-hop distance  which can reach 4400 kilometers in the best conditions, or at least some hundred kilometers by tropospheric dispersal of the signal, or still more than 500 km by reflexion on sporadic E layer.

 

 A good listening report  

The listening reports are the only rewards of  a beacon operator. Indeed, these reports tell the operator which were the favorable periods of propagation from his QTH. This information is highly interesting for the beacon operators. By these observations and exchange with other people interested in propagation, they can contribute to a better understanding of phenomena inherent to radio propagations.

The minimal information of a listening reports should be:

n     universal time (UTC), and date at which the signal was heard  

n    the QTH, or the location where the signal were copied

n     signal according to the code RST convention

n     frequency

n     mention if the signal underwent some fading (QSB)

You can complete with your conditions of operation, such as, what kind of antenna and used receiver you use. Any other comment concerning the state of the propagation, quality of the audio, or presence of interfering signals is always welcome. The operator of a propagation beacon will always be pleased to receive your comments and to answer your questions concerning propagation and his beacon.

 

 

 

The wave propagation for 6 and 10 meters band

My interest towards the bands of 6 and 10 meter bands (50 and 28 mhz) rest mainly in the similarity of these two bands, regarding waves propagation. Indeed, it is now more than 50 years ago that 30 mhz was chosen as the separation point between HF and VHF. At this time, the properties and characteristics of these ranges of radio frequencies radio were not yet perfectly known. So, it is not so surprising to notice that even separated by more than 20 mhz, these two bands are subject to several types of identical waves propagation. The ten meter band  (28 mhz) is a HF frequency , but it behaves in several aspects like a VHF band.    

 

Here are some kind of waves propagation which make possible communications beyond  the horizon line with the six and ten meter bands.

 

 

 

 

The F layer propagation

The  ionospheric F layer is the highest in altitude, being situated between 150 and 500 kilometers, it is the layer which gives the most distant contacts and one of best quality of transmission. It’s possibilities will be especially appreciated in the daytime during winter, with contacts exceeding

20 000 km. The ten meters band is the one that benefits most of this kind of propagation, because good conditions will be more frequent and lasting on 10 meter than on 6 meter, even if low power is used. However the solar flux  has to reach a value of 110 in the solar flux intensity on ten meter for the signal to be reflected, in about six of the eleven years of solar cycle, this band can provide good propagation. As for the 6 meter band, will only when the solar flux is at it’s maximum will contacts be possible by way of the F layer. A minimum solar flux intensity of at least 200 will be generally be necessary in winter period to make possible contacts by  way of  F1 and F2 layers. Single hop distance should be of the order of 3500 to 4400 kilometers.

 

 

 

The E layer propagation

Propagation by way of  E layer is very interesting because it is practically unpredictable. This ionized layer is situated at about 105 km in altitude and it’s effects are felt mostly in the daytime and more rarely at night .

E layer can support contacts on the HF bands and up to the 2 meter band in VHF. As regards the frequencies of 28 and 50 mhz which are our main concern here, they are probably the most favored by the reflection of the waves by E layer.

In HF, when there is propagation by way of E layer, one says, short skip  propagation, because the stations contacted  can be distant from only some hundred kilometers. This phenomenon indicates that the " MUF " or maximum usable frequency is superior to the  frequency used and that the signal is reflected with an angle of incidence much higher than normal, which reduce the skip distance . It is also presumable that communications can be established on more higher frequencies.

The maximum single hop distance by way of E layer, independent of the frequency is about 2200 kilometers. There can be more than one hop by way of E layer, or another skip combination between E and F layers, so that communications over distances of more than 6000 kilometers are possible.

The main peculiarity of E layer remains however made that it can produce a strongly ionized limited area called  E cloud sporadic. This ionized area then allows contacts between well defined regions, because these clouds ionized  dimensions are only between 80 and 160 kilometers in diameters and have a speed of movement from 240 to 400 kilometers per hour, in a west or north-west heading. In these ionized clouds of the  E layer, MUF can increase from 28 to 50 mhz in a matter of minutes. Due to all these factors, the length of time when contacts by way of  sporadic E layer are possible can be of very short duration, which explains the frantic short exchanges between hamradio stations during these openings on the 6 meter band.

These openings are less spectacular on the 10 meter band.. Indeed, contacts can last much longer because at lower frequencies, the MUF frequency will be able to support contacts over a longer period. It is mainly the distance limited to about 2200 kilometers, the strong signals, and the fact that contacted stations are from the same geographic area that will indicate to the radio operator that these contacts are due to sporadic E layer propagation.

In the northern hemisphere, it is between May and August that sporadic clouds in E layer happen. The most favorable hours are between 9 and 12 o’clock, and 17 and 20 o’clock local time. It is to note that there is still no established correlation between solar activity and the frequency of openings radio by way of sporadic E clouds.

 

 Backscatter and sidescatter propagation

This kind of propagation occurs when the maximum usable frequency « MUF » is higher than the frequency in use. The most part of the  radio wave is reflected forwards, but a small part of  it’s energy is returned back for backscatter or aside for sidescatter. The ionization of E and F layers is then intense enough to return part of the wave towards the site of emission, or sideways, rather than only forwards towards the ground. It can also happen that when the wave strikes the ground after a first hop, a part of  it’s energy return back to the ionosphere and in the direction of the origin of emission or aside from it. Signals by way of these types of propagation are generally stable but weaker than normal and little affected by fading QSB. Modulation in phone mode is easily and gives the impression of hearing somebody  talking in a pipe with a faint echo. What is much more remarkable it is that the contacted station can be located some hundreds of kilometers away, a distance usually too short for contact and within the silence zone. This kind of propagation can also reach 2000 km. It is to be noted that improvement in the sensitivity of modern receivers and more efficient antenna have helped making use of  this kind of propagation. Frequencies of 50 mhz and of 28 mhz are both subject to this type of  wave propagation.

 

   

Trans-Equatorial propagation

Trans-equatorial propagation favors regions located at most in about 2500 km on both side of the magnetic equator. It is necessary however to keep in mind that magnetic equator is not the same as the geographic equator  which one knows from maps, in the same way as the magnetic north is not located where the geographic north is.

The northern half of the United States, as well as Canada, is little subject to this kind of propagation, while the most part of Europe is within 2500 km from the magnetic equator. Trans-equatorial propagation appears from July till October in the maximum of solar cycle activity and can also happen in September during the minimum of the same cycle. It is after sunset, between 20 and 23 o'clock,  local time, that possibilities of contacts are best. It is a wrinkling in the ionosphere above the magnetic equator and encircling it, which would bring about a double deviation of the wave on both sides of this wrinkling over the magnetic equator. Contacts from 14 mhz up to 430 mhz in the UHF, can take advantage of this type of propagation. Stations communicating by trans-equatorial propagation are located on each side of  the magnetic equator at similar distances from it. However stations can be situated on very different meridians, such as  contacts connecting India and South America. Contacts from 2500 to 8000 km can be made.

 

 

Tropospheric scatter propagation

Generally, tropospheric scatter appears during a temperature inversion, when propagation by dispersal tropospheric finds the meteorological elements necessary for this phenomenon.

The troposphere is the space of air included between the ground and 5 kilometers of altitude at the poles, and 18 kilometers of altitude at the equator. As for us, it is between the ground and  ±10 kilometers in altitude that the air masses produce this type of  radio waves propagations.

During a temperature inversion there is a superposing of a warmer and damper air mass over another colder and dryer one. It is then between these two layers of air of different densities that radio wave  remains trapped and can travel some hundred of kilometers. The VHF and UHF bands are generally favored by this propagation mode. As for the effects of this kind of propagation on 28 mhz, there is little informations on the subject. Personally I believe that it there may be certain positive effects and maybe also negative effects, caused by tropospheric scatter. We may be able to observe this phenomenon during the next solar minimum.

 

 

 

Meteor scatter propagation

This kind of propagation is highly appreciated by numerous of radio amateurs operating the VHF band. Frequencies of 28 and 50 mhz are favored with propagation by way of reflections on ionized tracks left by the entrance of micro-meteorites in the atmosphere.

Reflection or dispersal of waves happen on air which was ionized by the passage of meteors. Indeed, by passing through  the atmosphere at high speed, they reach a very high temperature and melt away, leaving a trail of ionized air between 80 and 150 kilometers in altitude lasting a fewseconds.  These ionized trails can then reflect frequencies from 28 to 432 mhz. When there is a significant shooting stars shower of plentiful and constantly falling micro-meteorites, it is possible to make short contacts. The perseids of August 12 which offers the best chances of contacts. When a radio signal intercepts the ionized trail left by a micro-meteorite, it is possible to experience a return of signal of the order of 40 db and a shift in frequency (Doppler effect). Such a shift of up to 2 khz has been observed, due to the very fast movement of the source of the reflexion. For these reasons, digital modes passing informations quickly are best adapted.

During the most intense shooting stars showers, a few watts and a simple directional antenna are sufficient to make contacts on frequencies of the 28 and 50 mhz, stations distant from 200 to 2300 kilometers can be contacted.

 

 

Auroral propagation

For stations located in middle latitudes, it is possible to make contacts by reflection on auroras borealis or northern lights for the northern hemisphere, or auroras australis for the southern hemisphere. Contacts will  then be limited to a zone circling each hemisphere and, at most, at 1100 kilometers from the aurora. However, the more one is situated near the poles, the better will be the opportunities to establish contacts by reflection on auroras.

Auroras are caused by particles ejected from the sun which are captured by the earth`s magnetic field and attracted towards the polar regions. These particles react with oxigen and nitrogen atoms present in the atmosphere, by forming a sort of brilliant curtain in movement, wich is the aurora. It is during magnetic disturbance when there is an abundance of material thrown by the sun towards the earth that auroras occur with an intensity sufficient to  support reflection of  radio waves. For this kind of communication, direct the antenna northward and  adjusts it for the strongest signal reception signal. One recognizes easily a signal reflected by an aurora because of a jerky audio with a certain tremor. The QSB or frequent fading in this type of contact is caused by the irregular shape and constant movement of  the aurora. QSB results also from multiple reflections on the front of the aurora causing a fast change in the phase of the signal. Due to the characteristics stated above, cw is the prefered mode, even though phone contacts  are generally possible, with more or less ease, depending on the intensity of the aurora. Radio signals reflected by auroras are generally of weak to moderately strong levels, and these conditions can last from some minutes to few hour. Contacts between 400 and 2000 kilometers can be established, the wave can then be reflected then more or less towards the transmitting station for backscatter,or aside for sidescatter. The best periods are in spring and in autumn between 22 and 3 o'clock, local time. Contacts on frequencies between 28 and 432 mhz are possible even though it is the 50 mhz which is most favored. The frequency of 28 mhz should normally be reflected easily by auroras, needing a less intense ionization to be reflected. The HFoperators seem little interested in this mode of propagation, probably out of misunderstanding the phenomenon on the HF bands, or believing that it is rather reserved only for VHF frequencies.  In HF, auroras are rather considered as a nuisance by causing an audio quality called arctic flutter, when radio signals passes near the poles and are affected by auroras.

 

Thanks to  

It is in 1998 that I began project for the installation of a beacon  to operate on the band of 10 meter. It is with help of my father Rosaire, Gilbert Bergeron VE2FGE and encouragements of Marc Cimon AI7F, that this first beacon (VA2MGL/BCN) begin transmitting in August 1999.  

In winter 2001, the preparations for the installation of a second beacon for the 6 meter band began. The transmitter were built by Michel Lavallé VE2MJ, who in completed work begun by  Marc Cimon AI7F , now silent key. Once again I received the support of my father Rosaire and  Gilbert VE2FGE. The VA2MGL/B2 began transmitting in January 2002.  

Finally in autumn 2002, VA2MGL/B3 the third beacon operating on the 6 meter band  entered  in operation. The transmitter were built also by Michel VE2MJ.

Concerning the website project,, i received the help of my mother Andrée, Dominique Gagnon as well as Michel VE2MJ which gave me a help for the final  French and English revision of the web site.

Great thanks to all these persons who allowed these projects to be born.  

I would not miss  Guylaine VA2GGB, for supporting these projects, and those to come !  

Thanks  to  all.

                    Marc  VA2MGL

 

 

To contact me

You can join me by E-mail at :  va2mgl@arrl.net  

 

Or by mail at the following address :  Marc Gagnon

36 Ruisseau des Frênes

La Malbaie, QC

Canada  G5A 2C8