From São Tomé and Príncipe Islands for All over the World!

De São Tomé e Príncipe para Todo o Mundo!

Du San Tome et Principe pour tout le Monde!

 

 

 

 

 

Index

What is North West Africa Adventure?

Why Rolas Island?

Operator

Propagation  Over View and Frequencies

Visit this Paradisiac Islands

QSL and Logs-on-line

Others Stations from S.Tomé e Principe

Nature

Enjoy DX

Malaria and Yellow Fever

News

Index

Porquê o Ilhéu  das Rolas   

A localização

Propagação e Frequências  

Operador

QSL  e Diário da Estação

Outras Estações em S.Tomé

O Fascínio do DX 

Natureza

Visite São Tomé e Príncipe

Um Paraíso Tropical 

Malária e Febre Amarela

Notícias

 

 

  

ARLHS

 S92BWW

   Marq,S92BWW & Bill Moore,NC1L

Visit US! Visit S. Tomé e Principe!

Rolas Island Sunset 

    CQ14BWW Special Event

I'm member and QSL Manager

I'm using a Vibro Keyer

Propagation Overview

It has never been a secret that long-range communication in the amateur bands is primarily dependant  upon the ionosphere, however it is essential to visualize the structure of the ionosphere  and to understand more thoroughly the basic theory behind the usage of sky-wave methods of transmission if effective use the ionosphere is to be made. 

The Ionosphere's Structure

The ionosphere's overall structure consists primarily of three ionized layers ranging from 35 to 215 miles or so above the earth. The region lowest in height found at about 35 miles extending to 70 miles is called "D" layer and for all practical purposes, is useless to the amateur. Instead of reflecting radio waves, the "D" layer acts as an impediment and attenuates the signals strength to sometimes completely absorting 80 and 160 meter signals . 

Sunspot Cycles and Ionospheric Variations

Ultraviolet  radiation from the sun is believed to be the source of energy which ionizes the ionospheres numerous layers. This belief is constituted  on the basis of what is known as the 11-year sunspot-cycle.  Over a period of a few years, the number of sunspots  increases to a peak and then gradually declines, like this moment. The duration from  one sunspot peak to another usually covers about 11 years. During its peak , communicating conditions are excellent especially for 20, 17, 15, 12 meters bands and are even better on 10 meters.  We are approaching to the sunspot down and for worst conditions, contacts should be not so good. at a sunspot minimum or "sunspot dip" communicating ranges e poor with very few band openings. There  also exist what is known  as  ionospheric storms and when they occur, the critical frequencies drop considerably and absorption of radio signals in the ionosphere is substantially increased.  These ionospheric storms are resultant of certain sunspot activity. They usually last from few hours to several days.

Propagation Data

If the amateur has in his shack a wealth of propagation charts or just on or two of them, he will be much better off than the other amateur  who doesn't have any.  By a simple connection through internet to the Institute for Telecommunication Sciences and Astronomy, you can receive regularly prediction muf's for the upcoming days and other information.   

Cálculo de Previsões de Propagação

W6EL Prop é um programa que permite calcular as condições de propagação entre dois locais na terra nas frequências entre os 3 e os 30 MHZ. Este programa é gratuito quando usado sem fins comerciais.Download W6ELProp v2.70 (479,795 Bytes)

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Interest 1 http://www.stroobandt.com/propagation/propagation.html.

Interest 2- Grey Line Map http://dx.qsl.net/propagation/greyline.html

Interest 3 http://solar.sec.noaa.gov/rt_plots/kp_3d.htm

Interest 4- Estimated Planetary K Index  http://dx.qsl.net/propagation/propagation.html 

Interest 5- Auroral activity  http://solar.sec.noaa.gov/pmap/

Interest 6- Solar  http://solar.spacew.com/

Typical Operating Frequencies

The text search engine allows queries to be formed from arbitrary Boolean expressions containing the keywords AND, OR, and NOT, and grouped with parentheses. For example:

Frequências / Typical Operating Frequencies

Band

Mode

Frequency

160

CW     1.8265                             (listen 1.912 JA)

160

SSB    1.835 to 1.840

80

CW 3.506 and 3.523

80

SSB 3.795 to 3.802               (3.800 for VK)

40

CW 7.006 and 7023

40

SSB 7.052                          (listen above 7.200 for NA)

40

RTTY 7.037 and 7.080

30

CW 10.102 and 10.108

30

RTTY 10.140

20

CW 14.006 and 14.023

20

SSB 14.145 and 14195

20

RTTY 14.080

20

SSTV 14.230 and 14.233

17

CW 18.073

17

SSB 18.140

17

RTTY 18.102

15

CW 21.006 and 21.023

15

SSB 21.295

15

RTTY 21.080

15

SSTV 21.340

12

CW 24.895

12

SSB 24.945

12

RTTY 24.920

10

CW 28.006 and 28.023

10

SSB 28.495

10

RTTY 28.540

10

FM 29.260

6

CW,SSB,FM 50.115
web*

Let us know your necessities about Bands and Modes. send us your Request

Will try to give you more than one band and mode.

See you during DX'pedition!

N1MM Free Contest Logger

The software can be downloaded via the links at internet. It's a freeware program designed to do contest logging and some general logging.

It is not a general logging program with award tracking etc. but it is mainly a contest program.

Also very good for using as a DXpedinionary tools on any laptop .

The program can be used on Windows 95/98/ME and on Windows NT/2000/XP.DOS is not supported.

Try to use this log software and explore all facilities.

Radio interfacing

Interfacing to a radio is done directly with a serial cable (straight or crossed) . Every brand has it's own solution for it, also they have there own commands when changing frequency, changing band, etc. So always look in the manual what to use with your radio what to use.

Index  |Porquê o Ilhéu das Rolas   |  Aproveita o DX    | Operador  | Outras     Expedições    |    Qsl   | Patrocinadores   |  Propagação Frequências  |  Notícias ]

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