Technical Articles

Arrow Radio Propagation:

NVIS communications in the HF band

Daily evolution of the ionosphere

Geometry and operative aspects of the simple modes of ionospheric propagation

Analysis of the radio contacts between the Canary Islands and South America in the 50 MHz band in March 2010

NVIS Propagation: Study and Experiences (ESP)

NVIS propagation model: study of a practical case (ESP)

Planification of Radio Links in the HF Band (ESP)

Arrow Antennas:

Effects of the installation of VHF/UHF Monopoles at different heights

VHF/UHF monopole ground planes with 4 radials

Notes on antenna simulation using NEC-2

Arrow Radio Direction Finding:

Adcock/Watson-Watt Radio Direction Finding

Arrow Space Weather:

Risks derived from the Space Weather (ESP)

Impact of severe Space Weather events on the terrestrial radio communication systems (ESP)

Arrow Glossaries:

HF Radio communications glossary (ESP)

Emergency Communications glossary (ESP)

Arrow Other links:

EA4FSI's channel on Youtube

 


Other resources

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Technical Articles

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MainTechnical Articles

Welcome to the EA4FSI-28T1's technical articles page. If you want to submit comments or suggestions, please use this form.

Esta página también está disponible en español (this page is also available in spanish).

1. Articles about Radio Propagation.

NVIS communications in the HF band (Nov 2008).
Daily evolution of the ionosphere (Mar 2010).
Geometry and operative aspects of the simple modes of ionospheric propagation (Apr 2010).
Analysis of the radio contacts between the Canary Islands and South America in the 50 MHz band in March 2010 (Apr 2010).
NVIS Propagation: Study and Experiences. Memorial de Ingenieros nº37, year 1989 (Spanish Army Corps of Engineers Magazine). Reproduced with permission (Jul 2014, Spanish).
NVIS propagation model: study of a practical case. Memorial de Ingenieros nº39, year 1990 (Spanish Army Corps of Engineers Magazine). Reproduced with permission (Jul 2014, Spanish).
Planification of Radio Links in the HF Band. Spanish Army Corps of Engineers Magazine (Memorial de Ingenieros) nº92, July 2014 (Spanish).

2. Articles about Antennas.

Effects of the installation of VHF/UHF monopoles at different heights (Dec 2009).
VHF/UHF monopole ground planes with 4 radials (Dec 2009).
Notes on antenna simulation using NEC-2 (Ago 2012).

3. Articles about Radio Direction Finding (RDF).

Adcock/Watson-Watt Radio Direction Finding (Ago 2012).

4. Articles about Space Weather.

Risks derived from the Space Weather (Nov 2010, Spanish).
Impact of severe Space Weather events on the terrestrial radio communication systems (Mar 2011).

5. Glossaries.

HF radio communications glossary (Nov 2009, Spanish).
Emergency Telecommunications glossary (Oct 2010, Spanish).

6. Other links.

EA4FSI's channel on Youtube.



NVIS communications in the HF band

NVIS

Description of the near vertical incident skywave (NVIS) mode of propagation in HF, which allows communications up to 300 km without shadow zones.

Article published in the Spanish Amateur Radio Union Magazine.

Nov 2008. UK flag ESP flag

 


HF radio communications glossary

Glosario de HF

A collection of terms related with radio communications in the HF band. The glossary has currently 202 terms. Last updated on 28MAY14 (v8).

Available in Spanish only.

Nov 2009. ESP flag

 


Installation of VHF/UHF monopoles at different heights

Instalación de monopolos a distintas alturas

Analysis of the effects derived from installing a VHF/UHF monopole at different heights over ground, made with 4NEC2. The optimal heigths are determined and also the heights to be avoided, as a function of the calculated gain taking into account the antenna, the mast and the ground plane.

Dec 2009. UK flag ESP flag

 


VHF/UHF monopole ground planes with 4 radials

Monopole ground planes with 4 radials

Analysis of artificial ground planes for VHF/UHF monopoles, performed with 4NEC2. Includes ground planes made of 4 radials at 90 degrees and 45 degrees.

Dec 2009. UK flag ESP flag

 


Daily evolution of the ionosphere

Evolución diaria de la ionosfera

Educational video about the evolution of the different layers of the ionosphere during a whole day, using scientific data from the ionospheric sounding station "El Arenosillo", located in southwestern Spain.

Mar 2010. UK flag ESP flag

 


Geometry and operative aspects of the simple modes of ionospheric propagation

Geometría y aspectos operativos

This article describes the geometry of the propagation of radio waves through several hops using one of the layers of the ionosphere, a mode commonly used in the HF bands and also in the VHF and even the UHF bands under some circumstances.

Apr 2010. UK flag ESP flag

 


Analysis of the radio contacts between the Canary Islands and South America in the 50 MHz band in March 2010

Análisis contactos EA8-PY

Propagation study on the contacts made by amateur radio stations between the Canary Islands (Spain) and several countries in South America, in the 50 MHz band, between the days 17-21 March 2010.

Apr 2010. UK flag ESP flag

 


Emergency Telecommunications Glossary

Glosario de Telecomunicaciones de Emergencia

A collection of terms related with emergency telecommunications. The glossary has currently 167 terms. Last updated on 13OCT10 (v2).

Available in Spanish only.

Oct 2010. ESP flag

 


Risks derived from the Space Weather

Riesgos derivados del clima espacial

Report presented in November 2010 to the Spanish General Directorate of Civil Protection and Emergencies (DGPCE), on the occasion of the Technical Congress on Space Weather. Provides a description of the Space Weather phenomena and an analysis of the risks for people and several technological systems, as well as a description of the observation and early warning systems currently available in several countries. Available in Spanish only.

Nov 2010. ESP flag

 


Impact of the severe Space Weather events on the terrestrial radio communication systems

Clima Espacial Radiocomunicaciones

Lecture on the impact of the severe Space Weather events on the terrestrial radio communication systems, presented in the Spanish National Civil Protection School (General Directorate of Civil Protection and Emergencies, Ministry of Interior) during the "Conference on Space Weather", 23-24 March 2011. Available in Spanish only.

Mar 2011. ESP flag

 


Notes on antenna simulation using NEC-2

Apuntes NEC-2

Notes and recommendations about antenna simulations using software based on the NEC-2 algorithm, developed by the Lawrence Livermore National Laboratory. The recommendations and rules of design have been compiled both from the manuals of some programs and from technical articles about antenna simulation.

Article published in the Spanish Amateur Radio Union Magazine.

Aug 2012. UK flag ESP flag

 


Adcock/Watson-Watt Radio Direction Finding

Radiogoniometría Adcock/Watson-Watt

Technical description of the radio direction finding systems type Adcock/Watson-Watt, based on the employ of four monopololes with an additional sense monopole to avoid ambiguities. Those systems are commonly used in military environments (SIGINT), radio navigation and radio direction finding during emergencies, in the MF, HF, VHF and UHF radio bands. The theoretical explanation is backed by radiation patterns made with 4Nec2 and the analysis of the demodulated signals using a function plotting software.

Aug 2012. UK flag ESP flag

 


NVIS Propagation: Study and Experiences

Memorial

Transcription of the original article by the then Captain Julián Iranzo Collado of the 21st Tactical Signals Regiment of the Spanish Army, published in the "Memorial del Arma de Ingenieros" (Spanish Army Corps of Engineers Magazine), nº37, year 1989. Reproduced with permission. Available in Spanish only.

Jul 2014. ESP flag

 


NVIS Propagation model: study of a practical case

Memorial

Transcription of the original article by the then Captain Julián Iranzo Collado of the 21st Tactical Signals Regiment of the Spanish Army, published in the "Memorial del Arma de Ingenieros" (Spanish Army Corps of Engineers Magazine), nº39, year 1990. Follow-up article of "NVIS propagation: studies and experiences", published in the nº37 of the same magazine and also available in this site. Reproduced with permission. Available in Spanish only.

Jul 2014. ESP flag

 


Planification of Radio Links in the HF Band

Memorial92

A methodology for the planification of frequencies in the HF band, taking into account the network topology, its technical parameters, the ionospheric propagation conditions and the working bands with frequency allocations. Available in Spanish only.

The article was published in the Spanish Army Signals and Engineering School Magazine (Memorial de Ingenieros), in July 2014.

Jul 2014. ESP flag

 


EA4FSI's channel on Youtube



EA4FSI's channel on Youtube

 


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Ismael Pellejero - EA4FSI
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