FMSCAN - frequencies for any place and transmitter maps

What's on my FM dial?

The FM band looks different wherever you go. If you only a move into the next city there will be different stations on other frequencies. FMSCAN can calculate what to expect. It's a free tool.

Whether you just want to take a closer look at your stations at home or you are about to travel some distant spot - this tool helps to explore FM and AM radio.

Transmitter maps


The Network Maps section makes it easy to find frequencies of a specific station if you're moving through a certain area. This has been automatized with the RDS technology. But RDS often fails with weaker stations. Setting the frequency manually might deliver you many more stations than RDS would find.

FMLIST - the database

Part of the data comes from public sources. In addition to that FMLIST includes many observations from people who like to listen to distant stations (DXers). These hobbyists are also the most intense users of the database. Combining all this information makes FMLIST unique. In South Europe for example you won't gain much out of the official sources. FMLIST has become quite comprehensive over the years. It should contain almost any FM frequency in Europe, North America, the Middle East and most parts of Africa. Other contires are following. AM coverage is world-wide. The current coverage can be obtained by clicking on FM Coverage and AM coverage. There are also links on the start page. The FMLIST project started in Germany in the late 80ies. FMSCAN and FMMAP have been on the internet since around 2000. Since 2004 many international contributors have joined the project.

FMSCAN - My frequencies

Your own location

FMSCAN needs the coordinates for the place for which the automatic bandscan will be processed.

But you don't need neccessarily to know longitude and latitude. Just type in your location and select the appropriate result.

Other options for the location serach


"Click On Map" will display two sequential maps: fist the world map. Click on the area you are looking for. The second map will zoom there. Click again on the spot. Now your coordinates will be inserted automatically. Of course it is also possible to enter the coordinates manually. If cookies are allowed in your browser's preferences, locations will be saved. They should appear in a list when you return to the location serach.

The automatic bandscan (FMSCAN / My Frequencies)


Everything fine? Then click on the "generate" button. After a few seconds the frequency list appears. The strong stations are marked green. There is also a second list with the strongest frequency of each programme. This helps if you want to set the memory of your radio. They are ordered from the strongest to the weakest.

The columns

"f" stands for fading. That means: the signal strength gets stronger and weaker all the time and often disappears for a few seconds because it is beyond the FM horizon. Fading depends much on the weather.



Click on the list !

Clicking on the fields will display more information depending on the column

With a click on 'info' at the very right you can get all the basis data for the entry at once glance. Where available you will find play icons to the livestreams.

Other clickable columns:

Frequency:

you can choose between

Programme:

Transmitter:

List all frequencies and programmes of this transmitter. Further options:

Pmax

360-degree patterns for effective height (HAAT) and power (ERP)

Interpreting signal strength

How many "dB" are enough for good reception? This depends very much on the receiver and the antenna. Some sufficient levels: Even if the signal level is sufficient, neighbouring channels can interfere. If a station 0.1 MHz apart is only a little stronger, all receivers will face problems. Most car radios and tuners will cope with a difference of 0.2 MHz a equivalent signals. Cheap receivers still have problems if a station 1 MHz apart is only a little stronger than the chosen signal.

How strong must a transmitter be?

1 Watt is already enough to cover a village, 1 KW is sufficient for a major city (if the antenna is high enough), 100 KW usually reach up to 120 km with a permanent signal. Behind this horizon, signals are rather weak and they begin to fade. A directional antenna can pick them up and provide sufficient but fading signal levels. The effective transmitter power is a product of the electric power of the transmitter and the directional pattern of the antenna. Most bigger transmitters are combined with antennas concentrating the power like a flat plate. No signals are needed above and below the antenna, all the power should cover the area. This is why the effective power often exceeds the transmitter power.

Change parameters

Click on "expert options" to change parameters.

Change location:

chose another place or map center

data filter:

reduces the list to the selected options. In combination with "list all stations" this can work as a database query. Most fields can reamain empty (common sense rules). Then they would take no effect.

Frequency:

the range of the query in MHz or just the single frequency. The database lists stations on FM from the East European OIRT band (65-74 MHz), some Japanese stations (76-92 MHz) and the international FM band (87.5-108 MHz).

List all stations (SCAN):

lists really any station from the database with the chosen parameters no matter what signal strength to expect.

Programme list (SCAN):

will show a list of the strongest frequency of each programme below the scan.

Radius

Usually an automatic preselction is active for each scan: for normal conditions only transmitters in a radius of about 300 km are being checked for example. But you can alter this preselection by setting a different radius here. in combination with "list all stations" a frequency list will all surrounding stations in this radius will be displayed.

dist/azi/dB:

The coulums for distance, azimuth and signal strength will be displayed. If you just want a list of all frequencies of a programme independet from your own location you can uncheck this option.

dBmax/dBdist:

in addition to the signal strength, two other values will be displayed in brackets:

RDS

RDS-PS-Code (the 8 character display in car radios) containing the program name.

RDS-PI

RDS-PI-Code will be displayed. These are 4 Hex-figures that help to identify unknown stations. Most receivers use it in the background. Some communication receivers can display it as a more or less hidden function.

HAAT (height above average terrain)

The effective height is the average height of the transmitter antenna above the surrounding terrain in 3 to 15 km radius. For the calculation of the signal strength this value is usually more relevant than the height above sea level. Just like we have two power columns, there are also two HAAT columns. One for the effective height towards the receiver and one for the maximum HAAT of all directions. Sometimes the second value is smaller than the first. That appears illogical. In these cases HAATmax is probably the average of all HAATs. The data is not always so consistent.

reg.program

Regional programmes will be displayed.

incl.inactive

inactive, temporary aqnd planned stations will also be displayed

Es Index

Every summer stations appear on FM from distances between 900 to 2600 km. Reception of one station lasts only a few minutes, signals change rapidly. If you are in Central Europe for example, one minute you can receive a station from Madrid, half an hour later stations from Valencia appear, later from Italy and so on. This phenomenon is called sporadic E or E(s) and is caused by reflections in the ionosphere (150 km above). With the Es index option, the bandscan only lists stations that are likely to appear under these conditions. The peak propability is assumed at 1800 km, strong stations within 1200-2100 km also listed at the top. Stations that are closer to the equator are preferred.

MS Index

Meteor-Scatter-Index: This is another way of receiving distant stations. Once a meteor enters the atmosphere (happens all the time) it leaves a ionized trail behind for a few seconds. This causes reflections of FM signals in a distance of about 800 km. These signals are very weak and can usually only be picked up with directional antennas and sensitive receivers. With the MS index option, the bandscan only lists stations that are likely to appear under these conditions.

Tropo (SCAN):

This refers to the most frequent overspill caused by inversions in the troposhere (up to 15 km). Light tropo enables repeption up to 200 km, strong tropo or ducts (intense inversions into one direction) lead signals up to 1200 km, or even further under conditions like above the Mediterranean Sea. Under normal conditions the tropo index is 0, extreme overspill can be simulated with a value of 9. Look up the Hepburn tropo index for today's conditions.

Threshold (SCAN):

only signals above this level will be displayed

weaker signals (SCAN):

in most cases it makes sense just to list the strongest staions on each frequency. The weaker ones won't be received anyway. This value sets the range below the strongest station. If it has a strength of 50 dB and the weaker stations value is 10 dB, stations down to 40 dB will be displayed. You can deactivate this by setting the value far up.

output limit

Maximum number of stations in the list. The limit is 10.000.

Antenna (FM/TV):

use QTHAAT

The relative height (HAAT) will automatically be calculated for the receiver's location (QTH). In other words: the topography around the receiver will be taken into account in 10 degree sectors when a scan is generated. If you click on QTHAAT a seperate window will open showing the height values of the receiver.

antenna above ground

this value will be added to the height above sea level when calculating the receiver's HAAT.

Receiver HAAT (FMSCAN / TVSCAN):

relative antenna height of the receiver (see HAAT above). This value will only be used if you don't use QTHAAT.

Gain/FB/azimuth/opening

Transmitter maps (FMMAP / MWMAP):

Network Maps

With a few clicks you can display the coverage and frequencies of any programme











additional expert options for maps:



Coverage

If checked, circles and ellipses will appear on the map indicating how far the signal can be received with a certain threshold level. Big threshold will result in small circles. Actually, this is not in perfect accordance with the bandscan's signal strength calculation. The calculation includes antenna height and power patterns.

Landscape ranges from 1 (flat) to 6 (mountains).



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