SOTA Mountain Explorer Award

This year 2025 I kept on with my SOTA trips, including Portugal (CT), France (F), Açores (CT2) and Iceland (TF). Meeting hams from all these places was always a pleasure, and a nice opportunity to learn about their culture, radio and their amazing places.

I suffered rain, fog and cold at Açores "tropical" islands, and then again while being to Iceland (that was more normal), but on the other hand, enjoyed the beatiful people and mountains around.

Special thanks to: Pedro Cruz CU2JX from Ponta Delgada, David F4JEP from Brive-la-Gaillarde, and Sigurdur TF3CW from Reykjavík. All of them helped me a lot, thank you again!

I have used different rigs during these trips: Yaesu FT-817, Lab599 TX-500, Elecraft KX-2, Venus SW-3B,... and several antennas too, almost all of them being simple wires: 10-20m linked dipole, 20/30/40m trapped endfed, 11m random wire endfed, etc. all of them onto a 6m carbon pole. I have also grabbed some smaller telescopic antennas, but I didn't use them.

Sometimes the Sun, CME's, poor propagation conditions or bad weather made the activations tough, but I always enjoyed them anyway. 

I strongly recommend you to live the experience of this kind of radio trips as a nice way to enrich your life experience.  

And finally, thanks to these travels I achieved the SOTA Mountain Explorer Award (Silver - CW). 

73 de Mikel!

20/30/40m trapped EFHW (EN)

Endfed trapped dipole for (15) 20, 30 and 40m

 

Pointed out in the picture are: the feeding point (bottom right),
the 20m trap (at the top of the pole), and the 30m trap (lower left)
Caravelas Mt, SOTA ref CT/TM-012 activation, august 2024

After a lot of SOTA activations and a lot of antenna types been used, at the end I decided to design and build one which meets some points:

- Easy and quick setup,
- ATU not needed
- lift up and lowering for changing each band not being necessary

The llast condition should be being able to handle a max of 20w power output, more adecuated for the equipment used on SOTA activations.

After having tested some antenna types -long wires, random, ground plane verticals, center fed dipoles, doublets, linked dipoles, etc.- and a lot of reading around Internet, I chose a resonant endfed (EFHW) trapped dipole design. The bands should be 20, 30 & 40m (plus 15m as the 3rd armonic of 40m) as the most common bands.

Even the design of a linked dipole is quite easier than using traps, then, during the activations, you are forced to stop the operation, leave the operating position, drop the antenna down, change the links configuration and sit again, every time you want to change the band. This is specially hard when you are searching for S2S QSOs on different bands.

 The traps design is more complicated, that's true, but the effort is made only once. Then, while activating, the ease of operation will be hugh. Band changes will be "automatic" -you will not need to move or stop operating- It will also diminish the damage to the pole caused for its manipulation.

Being a endfed antenna its construction will be easier, as you will only need one trap for each band (not as on the center fed dipoles, were a trap by leg is needed)

The endfed antennas need a shorter coaxial cable than the "normal" dipoles. This will make the antenna weight lighter and the coax attenuation smaller.

Amongst all the designs I have seen and studied, I found one that caught my attention: an EFHW for 20 30 and 40m, no tuner needed. I am talking about Dan's AI6XG one (https://www.ai6xg.com/post/trapped-20-30-40-meter-efhw-antenna)

After reading it carefully, I decided to use his design, but after some slight changes. Dan's design does not use the most adequated toroids neither by material nor size. I wanted my antenna to be able to manage up to 15-20w too, so I thought the toroid sizes should be larger than Dans'. So, I will use a FT82-43 for the impedance transformer on the feeding point, and T68-6 for the traps (as the material 6 is more suitable to the trap frequencies -13.9 and 10.0 MHz (see https://toroids.info).

Talking about both the antena and transformer wire I will use 24AWG (0,4mm diam) enameled for traps and transformer, and silicon for the antenna itself.

When building the antenna, some points must be specially cared. The most critical is the resonance frequency of the traps.

There are two types of trap designs:

- You can make them resonant on a middle point between the two bands to be isolated (f.i. around 12 MHz on an antenna for 20 and 30m).

- Slightly below the LOWER frequency of the HIGHER band. That is, for an 20 & 30m antenna, the trap should be tuned at 13.9 MHz. If the antenna should be trapped at 30m -10.100 MHz, the resonance should be at 10.000 MHz.

The first design is easier, but then the lenghts of each band will be affected for the other band's lenght, making the adjustment quite harder. As we are talking about a three bands antenna, the matter will be larger!

Tuning of the traps is quite critical, and as far as the capacitor values commercially available are what they are, will we have to play with the coil sizes and turn numbers. It must be done using a well calibrated VNA or a dip-meter (if you can already find one)

Before adding or subtracting turns from the coils, you can try putting the turns closer or wider. That will change slightly the resonance of the trap. 

Be aware that after ending the coil adjustments, you should keep it fixed to avoid changes of the resonance. Glue, wax, or heat shrink tube can be used but, caution, this can change a bit the frequency. Check it before cutting the wires.

 

Trap assembly can be done in several ways: on a fiberglass circuit, on your own 3D design, a piece of plastic, or even on the air (with short ropes for strain relief). Just take into account that then the traps will suffer while mounted on the field or when you mount & dismount the pole.

Regarding the impedance transformer, even the theory says that, for an 1:49 ratio, 21 turns should be used (with a tap at turn 3 for the secondary wiring) starting with 3 or 4 turns more is recommended, and then after having adjusted the 3 wires (1 of each band) try to add or remove until you find the best SWR ratio. The secondary will be always at turn 3.

The said lengths of the wires are only approximated. As always, when working with antennas it is better starting with a larger length and cut than finding that we are short for the wanted frequency.

Contrary to we have said of a minimum SWR adjust for the Z transformer, the different lengths of each wire must be made to be resonant at the given frequencies, no matter which SWR ratio at. This should also be made using a VNA.

The setup must start with the upper bands (20m in this case with the 13.9 trap connected at the end of the wire), once this done, we will connect and adjust the 30m wire with the 10.0 MHz trap.

Wire length adjustments must be done while the wire is set at its final position (that is, angle and height). For this, we can use a longer wind wire that later we make shorter as more segments are added.

If we made the upper bands adjustments correctly, they should not be affected when adding more segments. If it is, probably the trap design is not ok, check it again.

Regarding the position of the antenna/pole on the field, please note the following:

- The impedance transformer should be, at least, at 1.5 - 2m height from the ground. Many antenna designs connect the antenna right to the rig at ground level. This could be more comfortable, but the ground losses will be larger too.

- The far end of the wire, that is, the segment of the 40m band, should be at least 4m height. Otherwise tuning the antenna for 40m could be impossible.

- The antenna could be slightly directional, on the direction of the wire, mainly on the upper bands, as the configuration is something like a sloper design. (view the picture below)  

The radiation lobe will be very wide, and the directionality low, but it must be taken into account while choosing the operation position on the field. This sometimes will mark how we will be located at the summit, depending on the tree or trigger we choose as the pole support point.

- Regarding the counterweight, we have several options:

Use the coaxial wire itself. This should be at least 1.5-2m long for the feeding point to be at 1.5m or higher. If we make it a bit longer, say 2.5-3m, it will work better on the lower bands.
If when we use this option we have CMC (RFI at the rig, CW keyer, or mic) we can put a 1:1 RF choke of 10 turns of the coaxial itself onto a FT82-43 toroid, located just on the BNC connector of the transceiver. 

We can also use a wire of 0.045 wave lengths of the lower band (40m) which should be connected at the Z transformer on the opposite end of the primary coil. It can be left on the ground below the radiating wire. 

I hope this antenna to give you as many good times as to me. Do not hesitate to contact me to solve any problem or doubt. Find my e-mail address at qrz.com

73 de Mikel EA2CW | AE2CW

20/30/40m trapped EFHW (ES)

 Dipolo con trampas alimentada en un extremo de 20, 30 y 40m

End fed trapped dipole for (15) 20, 30 and 40m 

 

En la imagen están señalados el punto de alimentación (abajo a la derecha), la trampa 
de 20m (en el punto mas alto del mástil) y la de 30m (algo mas abajo a la izquierda)
Activación del monte Caravelas ref SOTA CT/TM-012, agosto de 2024

Tras muchas activaciones SOTA y haber utilizado muchos tipos de antenas, finalmente me decidí por diseñar y construir una que cumpliera con varias condiciones: 

- que fuera fácil y rápida de montar, 

- que no hiciera falta acoplador de antena y 

- que no hubiera que estar subiéndola y bajandola para cada cambio de banda. 

Como última condición, debería soportar una potencia máxima de 20w -algo mas que QRP- adecuada a los equipos que usamos habitualmente en SOTA.

Tras experimentar con bastantes tipos de antenas (hilos largos, random, ground planes, dipolos clásicas, doublets, linkadas...) y depués de mucho leer por Internet, me decidí por una dipolo alimentada en un extremo, también conocida como endfed o EFHW (End Fed Half Wave) con trampas. 

Aunque el diseño de una dipolo "linkada" es mucho mas sencillo que usar trampas, mas tarde, durante las activaciones, te ves forzado a parar la transmisión, levantarte, bajar la antena, cambiar los "links" y volver a sentarte cada vez que quieres cambiar de banda. Esto es especialmente farragoso si andas a la caza de QSOs SOTA to SOTA (S2S). 

El diseño de una dipolo con trampas es mas complicado que el de las linkadas, es cierto, pero es un esfuerzo que se hace solo una vez. Mas tarde, simplificará enormemente la operación durante las activaciones. El cambio de banda será "automático" -no necesitas moverte ni interrumpir la transmisión- y además disminuirá el desgaste de la caña, al no tener que subirla y bajarla o recoger y desplegar los tramos para cada cambio.

El que la antena esté alimentada en el extremo (endfed) simplifica su construcción, ya que solo hace falta una trampa por banda y no dos, como sería en caso de que fuera una dipolo alimentada en el centro (una trampa por rama). 

Además las endfed conllevan el uso de un cable coaxial mucho mas corto que las dipolos "normales", lo que disminuye, por un lado, el peso de la antena y por otro la atenuación de la señal debido al coaxial. 

Entre todos los diseños que he podido consultar en Internet, y sobre todo en el reflector de SOTA, encontré uno que me llamó la atención. Era una dipolo alimentada en el extremo, con trampas y para las bandas que mas suelo utilizar: 20, 30 y 40 m, con la posibilidad añadida de usarla en la banda de 15m (3er armónico de 40m). En todas ellas sin acoplador. Me refiero al diseño de Dan AI6XG y que tenéis en su página:

https://www.ai6xg.com/post/trapped-20-30-40-meter-efhw-antenna

Después de leerlo, y teniendo en cuenta el resto de documentación consultada, me decidí a usar su diseño pero adaptándolo. Este, a mi parecer, no usa los toroides mas adecuados, ni por material ni por tamaño. Quería que mi antena pudiera soportar hasta 10/20w, por lo que los diámetros de los nucleos, tanto del transformador de impedancias como de las trampas, deberían ser mayores que los que Dan propone en su proyecto. Así, usaría un FT82-43 para el transformador de impedancias. Para las trampas, el diámetro sería de 68 y no de 50 y el material 6 y no 2, ya que este último es mas adecuado para las frecuencias de las trampas (13,900 y 10,000 MHz) (ver https://toroids.info).

En cuanto al hilo, usaría cobre esmaltado de 0,4mm de diámetro para el transformador y las trampas y del mismo diámetro con aislante de silicona para la antena.

Para su construcción, hay que tener en cuenta especialmente los siguientes aspectos:

- El punto mas crítico es el ajuste de la frecuencia de resonancia de las trampas. 

Hay dos tipos de diseños de trampas: 

- Sintonizadas en un punto intermedio de las bandas a separar (por ejemplo, alrededor de 12 MHz para una antena de 20 y 30 m), o bien

- Ligeramente por debajo de la frecuencia mas baja de la banda mas alta. Es decir, en este ejemplo, para una antena de 20 y 30m, la trampa estaria sintonizada en 13,9 MHz. Para 30m, en 10 MHz, es decir, unos 100 KHz por debajo del principio de la banda,

El primer diseño hace que la resonancia de la trampa sea menos crítica, pero luego las longitudes de los dos tramos (antes y después de la trampa) interactúan entre sí, dificultando bastante su ajuste. 

Si estamos hablando de 3 bandas -o dos trampas- la cosa se complica todavía mas.

- El ajuste de las trampas (dado que el valor de la capacidad está limitado a los valores disponibles comercialmente, salvo que queramos usar pequeños trozos de coaxial como condensador) es bastante crítico. Debe hacerse usando un VNA bien calibrado, o si todavia disponeis de alguno, de un dip-meter. 

- Antes de añadir o quitar espiras, se puede probar a juntar o separar las espiras del bobinado. Esto modificará ligeramente la frecuencia de resonancia de la trampa.

- Ojo! Después de ajustar las trampas hay que inmovilizarlas para evitar que varíe la resonancia. Se puede usar pegamento, cola, cera o funda termorretráctil, pero cuidado, esto puede hacer variar ligeramente su sintonia. Comprobadlo antes de seguir. 

- El montaje físico de las trampas se puede hacer de muchas formas: sobre una placa de circuito impreso sin cobre, sobre un diseño 3D, con una placa de montaje, un trozo de plástico, o simplemente al aire. Solo tened en cuenta que van a soportar tensiones cuando estén montadas, y rozaduras al montar y desmontar la antena. 

En cuanto al transformador de impedancias, aunque la teoría dice que debería ser una bobina de 21 espiras para una relación de 1:49, con una toma a 3 para el bobinado secundario (el que luego irá al equipo) se recomienda partir de un número de 3 o 4 espiras mas y al final, una vez ajustadas las longitudes de los hilos de cada banda, probar a quitar una o mas espiras, hasta encontrar el número de espiras del primario que dé la menor ROE posible. El secundario será siempre de 3 espiras.

La longitud indicada para los hilos de cada banda es orientativa. Como siempre que trabajamos con antenas, es mejor partir de una longitud algo mayor y cortar, que ir justos y encontrarnos con que la antena está corta para la frecuencia deseada.

En contra de lo dicho para el transformador de impedancias (ajuste a menor ROE), el de la longitud de los tramos de cada banda debe hacerse para la resonancia de cada elemento. Buscaremos que sea en las frecuencias deseadas, independientemente de la ROE que presenten. Este ajuste se debería hacer también usando un VNA o un analizador de antena. 

También como siempre, los ajustes deben comenzar de arriba hacia abajo, es decir, conectaremos primero solo el tramo de 20m y la trampa de 13,9 y ajustaremos. Una vez hecho, añadiremos el tramo de hilo de 30m y su trampa (la de 10,0 MHz) y finalmente el tramo de 40m. 

Los ajustes deben hacerse de forma que el tramo que estemos ajustando esté en la posicion (altura, angulo, etc) que tendrá luego en su configuracion definitiva. Para ello podemos usar un viento mucho mas largo que luego iremos acortando conforme vayamos añadiendo tramos.

Si hemos hecho bien el ajuste de las bandas mas altas, éste no debe verse afectado (o solo muy ligeramente) al ir añadiendo mas bandas. Si cambia, es que el diseño de las trampas no es correcto.

En cuanto a su colocación, tener en cuenta los siguientes puntos:

- El transformador de impedancias del punto de alimentacion, debe estar al menos a 1,5m de altura sobre el suelo. 

- El otro extremo de la antena, es decir, lo que sería el final del tramo de la banda de 40m, deberá estar al menos a unos 4m de altura. De otro modo será dificil ajustarlo para una ROE baja. 

La antena puede ser comportarse de forma ligeramente direccional, en el sentido del hilo, en las bandas mas altas (15, 20 y 30m) o incluso en 40m, ya que sus tramos están dispuestos como una "sloper". La dirección de maxima radiacion será desde el final del tramo de 40 hacia el punto de alimentación. Es decir, si nos ponemos operando mirando al Norte, con la antena a nuestra espalda y la otra punta mirando al Sur, la antena radiará hacia el Norte. 

 

Es verdad que el ancho del lóbulo de radiacion será muy grande (muy baja direccionalidad) pero es importante que lo tengamos en cuenta a la hora de colocar la antena para operar. Es el punto débil de las endfed... Si en una cima encontramos solo un vértice o arbol al que podemos anclar el mástil, la endfed nos "marca" donde tendremos el punto de alimentación, vamos, dónde nos tendremos que sentar.

En cuanto al contrapeso (counterpoise / contraantena) tenemos varias opciones:

- Usar el propio cable coaxial de alimentacion. Este ya tiene que tener al menos 1,5-2m de longitud para que el punto de alimentacion esté a 1,5m de altura. Si lo alargamos a 2,5-3m de largo, funcionará mejor en las bandas bajas.
Si este sistema nos da problemas de RF en el equipo (common mode currents), tendremos que usar alguna otra de las siguientes opciones.

- Poner un choque 1:1 (10 vueltas del propio coaxial sobre un toroide FT82-43) colocado justo a la entrada del coaxial al equipo, y un hilo que ejerza las funciones de contra-antena (ver siguiente párrafo)

- Poner un hilo de aproximadamente 0,045 longitudes de onda de la frecuencia mas baja (40m en este caso)r. Podemos probar con uno algo mas largo e ir recogiéndolo hasta obtener el mejor resultado. Este hilo puede colocarse elevado (mejor) o tirado por el suelo, e idealmente, paralelo a de la antena (que quedaría encima suyo.

El hilo del contrapeso va conectado en el punto de alimentación de la antena, en el extremo común de los bobinados primario y secundario, es decir, en el extremo opuesto de la bobina al de donde sale el hilo de la antena.

Espero que esta antena os de tantos buenos ratos como me ha dado a mi. Quedo a vuestra disposición para cualquier duda que se os presente. Tenéis mi dirección de correo en qrz.com

73 de Mikel EA2CW | AE2CW

Mountain Goat

After 10 years being active in the SOTA (Summits On The Air) program, on august 19th, 2023 I achieved the  Mountain Goat certificate, after reaching 1,000 activator points.

This happened during my 2023 Soria (EA1) SOTA Tour, when I activated 13 summits from august 18th to 26th. It was on the second activation of the 19th at Mt Toranzo, ref. EA1/SO-11 for 6 points, making a total of 1,003 points.

 

Together with the forest warden I celebrated the event -with orange juice. She was explained the "weird" celebration, but then I knew that a close friend of her was also a ham operator. She called him by phone and we were able to share the moment remotely.

 

Of course I worked some of my usual VHF fellow chasers too. Despite of being on a quite unpopulated spanish province -Soria- I was able to qualify the summit on VHF with Julian EA2ETB, Fernando EA1AAP, Joaquin EA2CCG, Oscar EC2UT y Mique EA2EUS from the nearby territories of Nafarroa, La Rioja and Saragossa. 

Celebrating at Toranzo

After some chat with these friends, time for some QSOs on 20m CW. Not many, as the propagation was not the best, and I had the intention of making a 3rd activation that same day.

A long trip, ten years long, from my first summit, Arrola EA2/BI-053 on october 6th, 2013 to august 19th, 2023 on Toranzo. A bit older, but keeping the same spirit and a lot more experience!

Then I continued my tour until august 26, when after the 13th activation at Cabimonteros EA1/LR-033 and a 1,200 Kms trip, finally arrived at home. 

Waiting for the next one, thanks a lot to all chasers and activators which made all this possible!

EA2/BI-033 Sollube SOTA activation

Yesterday I made a short afternoon activation of Sollube Mt. (SOTA Ref. EA2/BI-033) near Bermeo, at the biscaine shore. This is a drive-in summit, full of communication towers, and where the RFI on VHF and UHF bands, are huge. 

My goal for this activation was to test some portable equipment recently arrived to my station or being there for long time but not being used before. In this particular case, the targets were my new Xiegu X6100 portable rig, and the JPC-12 antenna, and how they would work together. Also we wanted to check how the new FT8 android apps work in order to use them as a compact SOTA digital station. So I carried all the wires and connectors needed to do so.

Sollube, EA2/BI-033

When arriving to the summit around 15:30 local time, the weather was sunny and temperature about 23ºC, with no wind. One of the tests I wanted to do was checking whether the antenna could be able to manage a medium wind without using any kind of help -say 3 rope winds- but this could not be be made under these conditions.

The antenna

Once all items out of the rucksack, first thing to mount was the JPC-12 antenna. This antenna can be found on a number of well known chinese stores, as at USA and EU radio gear commerces as well. It consists in a metallic pike, 4 aluminum tubes, an adjustable coil and a telescopic wipe. All together makes a 4.2 m high vertical multiband antenna, working from 7 to 50 MHz bands to up to 100w output. When stored back in its bag (already provided),  its length is only 33 cm, weighting about 1.4 Kg. It also brings 10 radials of very thin wire (computer flat ribbon wire type) working at ground level.

JPC-12 antenna

Obviously, being supported by a pike, you need a specific kind of terrain, making it difficult to install on rocky or sandy ones. Probably on these cases, some paracord winds tied under the middle coil might be used to secure it. I think the supplied pike is a bit short for the height of the antenna. The builders could use the bag size to implement a 33cm pike instead the actual 25cm one, making it a bit safer at least.

All the parts use the same M10 screw mounting, so it's very easy to tie all them together, being it quite intuitive and fast. The mounting order is: ground pike, feed point (PL-259 type), 4 aluminum rods, adjustable coil and finally the telescopic (2.4m) rod. Don't forget (as I did) to connect the gound wires between the pike and the bottom side of the feeder before going on. The parts cannot be mounted on a wrong way due to male-female connections, but they can be mounted on a wrong order. Be careful on this, I have already read on the net that some people have mounted the adjustment coil on the base, just after the feeding part. On the other hand, this one have a rugged surface, very useful while sticking the pike to the ground.

The user manual (also included) tells to deploy at least 3 radials, but being at ground level and no tuned, I chose to install all of them. To do this you must take apart all the thin wires that come joint as a ribbon, and then distribute them evenly around the antenna.

Once the antenna installed, my intention was to adjust it on the different bands using the nanoVNA which I previously had calibrated at home. No way. Due to the strong RF signals at the summit, the readings were continously changing, showing random weird values. Same thing has already happened to me on several similar RF seriously polluted summits. Fortunately, the X6100 has an option of SWR check which later provided me with at last a rough measure of the behaviour of the antenna.

So that I did. Install and connect all kind of items to the transceiver, that is: microphone, battery (5200 mAh Lipo 3S 11.7v), cw iambic keyer, usb C cable and BNC antenna connector. For this I used a short 2m RG-174 male PL-259 to male BNC with a small choke on the radio side, trying to avoid RF signals on the usb connection to the phone (and it worked!)

Once the Xiegu turned on, the first thing to remark was that the display. It was easily seen, despite the sun light (my phone was not so good on this when taking the photos). I adjusted the antenna to the proposed point of the coil for the 20 m band (it has two marks, for 20 and 40m bands), change the rig to the SWR check mode and run it. I had to change only one turn (making the virtual length of the antenna longer) to have it at 1.3:1 ratio over all the 20 band. Actually, the minimum span of the X6100 check is 1 MHz, so I could see the SWR value from 13.9 to 14.9 MHz. 

More fine adjustment can be done by shortening slightly the telescopic rod, but in this case, it was not necessary. I was really surprised by the width of the working range, being a "short" antenna, loaded with a coil, at least compared with my previous experiences with other similar (but quite shorter) antennas. Almost the same happened on 30 and 40m bands, the adjustments being easy, wide, and accurate. I guess it can be due -at least partially- to ground losses caused by a basic radials system. 

In summary, the antena is well mechanized, strong, and easy and quick to be installed and adjusted, provided you have some way to check the SWR ratio on the chosen frequency. No need to use an ATU, so that is less weight you must carry to the summit. It performed well  on the 20/30/40m bands, having at sight that a quite strong CME was on, and the conditions were not the best. It could be appropiated particularly on small summits, where a pole supporting and EFHW or CF dipole could not be installed. OTOH, the 1.4 Kg weight and the size of its bag is not small and could determine the size of the rucksack needed.

The rig

As previously said, the first thing was the display. Even under strong sun light it was easily visible, a good point. The ability to check the SWR was also very useful. However, the use of the different options are not the most intuitive. Basic items -like power output adjustment, keyer speed, or RIT- are kind of hidden among other features not so commonly used. It would also be prefereable other kind of setting the freq stepping, for example, by pushing the main VFO knob. Better if you learn all these at home, before going onto work at the summit!

The waterfall is pretty, and capable of being adjusted on amplitude (other bigger and more expensive rigs cannot), but not particulary useful while SOTA activating, as usually you are going to stay on a fixed frequency, but it always can give you an idea of the band activity or conditions.

The noise reduction was not useful at all. Even on the lowest levels, the behaviour is extremely aggresive, making the signals weird and hard to be copied. Some firmware work have to be made in order to improve it seriously.

By this moment I had operated mainly on CW, but I also used SSB to check the clarity and readiness of my signals. The controls given were not the best, and I found the PTT switch of the mike a bit soft, not making a clear on-off, but overall it was not so bad.

Although the X6100 has its internal battery, the maximum power available when you use it is only 5w. In order to have up to 10-12 w (band depending) the use of an external power supply is a must. But be aware that any source giving more that 10-11 volts will cause a sensible heating of the equipment. So, LiPo 11.7 volts 3S batteries are strongly recommended. As an alternative, some kind of heat sinks attached to it can be used (There are some raspberry ones that can be easily adapted)

FT8 Android Apps

Although FT8 is not my preferred mode at all, this is quickly becoming one of the most used modes, and the needing of carrying some kind of computer (tablet PC, raspberry, etc) has refrained its use on portable scenaries. 

Now we have at least two android apps making possible its use with some rigs and a simple smartphone, that you probably are already carrying during your SOTA activations for using it as GPS tracker, for self-spotting, S2S QSOs and so. These are:

FT8 Radio (at 9.99$)

FT8CN by BG7YOZ, and freely available on Github

They both work with a number of rigs -using a bluetooth connection or via an USB OTG cable, like IC-705, Xiegu X6100, Lab599 TX-500, QDX, uBITX, etc. They all have an internal audio card, but it can be also used by means of an external USB audio card

Working procedures and interface are not similar to the usual WSJT-X way, and each one has its own particularities. I found FT8CN more adequated to my needs as activator as I am normally more interested on calling CQ and less on answering calls.With this one it is easier to find clear frequencies to call -using its own waterfall- and to keep your transmission freq fixed. In my POV, it also manages better the QSO interchange, but this is a matter of taste.

They are both in a developing state and must be still refined regarding to its operation procedures but the two give you a way to work this mode without carrying any suplementary equipment. 

Any further question? Please let me know, and thanks for reading, 73!

 

Consejos para una activación SOTA con éxito

 

Trataré aquí de resumir algunos consejos para conseguir una activación SOTA con éxito. Algunos de ellos son tan obvios que pueden olvidarse con facilidad. La mayoría provienen de mi experiencia a lo largo de 10 años y 300 activaciones, casi todas incluyendo la operación en telegrafía. 

Y recuerda: Cualquier activación será mas sencilla si llevas antena, equipo, una batería cargada, manipulador, bloc de notas y lápiz! ;-)

Nota: Casi todo lo expuesto puede aplicarse a cualquier tipo de activación SOTA, sea en VHF, HF, SSB, datos, etc.

Empecemos pues! En cualquier activación SOTA, existen una serie de cuestiones a tener en cuenta. Estas son algunas:

Antes de iniciar la activación:

• Planificación, planificación y mas planificación. En lo relativo al viaje, la ruta de subida, los tiempos, el periodo de luz según la epoca de año, la climatología, la zona de activación, cobertura de móvil, cobertura de repetidores de V/UHF y DMR, etc.
• Antes de comenzar el viaje, en casa, comprueba que tienes listos todos los elementos de radio: equipo, antenas, conectores, batería(s) cargada(s), micro, manipulador, bloc de notas, lápiz (bolígrafo), teléfono móvil, brújula, GPS, lo que sea. Procura hacer -y usar- una lista de comprobación, y revisar la mochila para asegurarte de que no has sacado nada desde la anterior activación.
• Comprueba atentamente la previsión metereológica de la zona, te ayudará a elegir la ropa y elementos de refugio adecuados.
• Lo mismo para el resto del equipo: los 10 esenciales, comida, agua, ropa de repuesto, refugio, etc.
• Una vez hecho esto, pon una alerta en SOTAwatch. Al hacerlo, el sistema  RBNhole te "espoteará" automáticamente durante tu activación en cualquier frecuencia de CW en la que transmitas, en un intervalo de -1 a +3 horas de la que hayas puesto en la alerta. También, en otros modos, servirá para que los cazadores estén atentos a tus transmisiones y, opcionalmente, pongan sus propios spots en SOTAwatch.
  
• Si formas parte de algún grupo local de SOTA (correo-e, redes sociales, etc.) infórmales de tus planes. Haz lo mismo con tus amigos y/o familia. Intenta mantener el GPS de tu teléfono móvil activado, será util para ayudar a localizarte en caso de emergencia.

Una vez en la activación:

Ten siempre en cuenta que una activación SOTA está caracterizada por una serie de factores. Tu seguidad es el mas importante de ellos. El tiempo de luz solar, las condiciones atmosféricas, y tu estado de forma física determinarán también cómo será la activación. No te sientas obligado a operar en algún modo, banda, duración, etc. La hora de llegada y la duración de la activación que has puesto en la alerta son solo estimaciones, no un compromiso firmado. Las condiciones climáticas pueden cambiar, o echarse la noche. Por tanto, adecúa siempre la activación a tu seguridad. Dicho todo esto, ¡empezamos!

Prepara la antena, emisora y todos los elementos necesarios para operar (micrófono, manipulador, grabadora, bloc, lápiz, auriculares, etc). 

Intenta poner en el aire la mejor señal posible (antena, potencia, situación,...) Ayudará a que se te oiga y entienda mejor en caso de que avises de cambios de frecuencia, apagado de la radio, llames a indicativos parciales, etc. Piensa en la mejor estrategia potencia / duración de la batería a usar para lograrlo.

Una vez que lo tengas todo listo, pon un "spot" en SOTAwatch (si es posible). Si no, también tienes la posibilidad de llamar por algún repetidor de V/UHF FM o DMR y pedir que te "espoteen". También puedes hacerlo por SMS o APRS. Comprueba si te hace falta. (¡Recuerda que ya lo has planificado!)

Haz una primera llamada CQ lo suficientemente larga para que sea detectada por el RBNhole. Incluye en ella la referencia de la cumbre.  Esto es especialmente importante en el caso de que no hayas podido poner un spot de la forma tradicional. El RBNhole utilizará los datos de tu alerta previa para publicar automáticamente esta información como un spot en SOTAwatch.

Cuando comiences a hacer contactos, mantente tranquilo. El comportamiento de los cazadores en el pile-up será un reflejo del tuyo. Si no puedes copiar un indicativo completo, pregunta por el indicativo parcial, pero siempre con calma y relajado. Los cazadores están en casa, no bajo una lluvia intensa, el frio o viento!

No uses una velocidad muy alta; tu señal probablemente no sea muy fuerte y debes ser claro y constante. Entre 20 y 25 ppm será mas que suficiente. Esto no es un concurso y tu objetivo es hacer cuantos mas contactos puedas, pero 4 son suficientes para validar la cumbre.

Intenta adecuar tu velocidad -si te lo permite el equipo- a la de tu corresponsal durante el QSO. Si no puedes, deja espacios mas largos entre los caracteres para que tu transmisión se pueda copiar mas fácilmente (Metodo Farnsworth)

Mantén un ritmo constante, p. ej. acaba siempre tus transmisiones con: [indicativo] TU 73 DE [tu_indicativo] K. Ayudará a que los cazadores sigan tu estilo de transmisión y a hacer mas contactos y mas rápidos. 

¡Nunca contestes a los que llamen "fuera de turno"!. Si llamas, p.ej. "AB1?", nunca contestes a un operador "BC2...". Si lo haces, el pile-up se volverá incontrolable. Sigue llamando "AB1?" hasta que te conteste o empieza nuevamente haciendo un CQ corto, llamando "QRZ" o similar.

Piénsatelo antes de contestar a los "tail-end"*. Si no, los cazadores seguirán llamando durante un largo rato tras tus llamadas.
(Tail-end es una técnica que consiste en llamar antes de que el QSO anterior termine, o esperar a que las estaciones mas potentes acaben de llamar y empezar mas tarde. Puede provocar que si no contestas a los primeros, estos se impacienten y repitan su llamada y asi sucesivamente)

Intenta escuchar un poco desplazado de tu frecuencia de transmisión, digamos entre 100 y 300 Hz hacia arriba o abajo. Hará que los que llaman se distribuyan un poco, tu frecuencia de transmision estará mas limpia y podrás escuchar los diferentes tonos mas fácilmente. Los cazadores se darán cuenta rápidamente de esta técnica y la utilizarán. Mejor para todos. 

Intenta también informar a los cazadores en el caso de que tengas que interrumpir la emisión para cambiar algún elemento (antena, batería, etc...), si tienes problemas con el tiempo, elementos caidos, pausas para comer o beber, dar explicaciones a los visitantes,... no desaparezcas sin explicación alguna -si puedes, claro.

Continúa mandando spots cuando cambies de banda o modo, tal y como ya hemos explicado.

Dependiendo de cuánta gente te esté llamando, repite tu indicativo y la referencia SOTA. A veces, dos activadores diferentes pueden estar en la misma frecuencia, alguien ha podido poner un spot incorrecto o, en el caso de activaciones conjuntas, haber cambios de operador. Puedes hacerlo cada 3-4 contactos si tienes poca gente llamando, o cada 10 o 12 llamadas. Si controlas bien el pile-up, puedes llegar a hacer hasta 2 o 3 contactos por minuto.

Una vez que disminuya el número de cazadores, valora si hacer unas cuantas llamadas mas o cambiar de banda, pero intenta permanecer en cada una al menos 10 minutos. Los cazadores no siempre están preparados para responderte nada mas poner tu spot. Además, algunos cazadores en QRP suelen esperar hasta que las estaciones mas potentes te hayan trabajado antes de llamarte. Dales tambien una oportunidad de hacerlo.

Ten siempre en cuenta: El tiempo que puedas estar operando depende de tu seguridad, de las condiciones climaticas, la temperatura, el tiempo estimado de vuelta al coche, tu condición física, etc. ¡Tu eres quien corre el riesgo y tu y solo tu quien decide!

Intenta seguir los mismos hábitos en todas tus activaciones. Los cazadores lo aprenderán y lo usarán para trabajarte. Por ejemplo, empieza en 20m CW, luego SSB, después 30m, mas tarde en 40m,... Usa si es posible las mismas frecuencias entre las mas utilizadas en las activaciones SOTA (por ejemplo, 14.063, 10.119, 7.034, etc). Esto también les dara pistas a los cazadores sobre dónde encontrate y ayudará a lograr una activación con exito.

Y recuerda: una activación fallida es siempre mejor que una arriesgada. El monte siempre estará ahi para que vuelvas otro dia. ¡Si sigues vivo, claro!

Como ya he dicho, toda esta información está basada en mis propias experiencias, y probablemente haya olvidado algun aspecto importante. Así pues, por favor, no dudes en ponerte en contacto conmigo y lo incluiré tan pronto como pueda. 

Gracias y buena activación!

73 de EA2CW 

ea2cw \arroba\ gautxori \punto\ com

DMR multiprotocol link

When you have different handheld models, or depending which DMR mode repeaters you have in sight while at the mountains

 Dashboards:

http://dmr4370.xreflector.es
http://dmr.pa7lim.nl

Links to the different modes / TG's /Rooms / Reflectors:

Brandmeister	TG 2140
D-Star	DCS015SL
YCS224 24	EA-C4FM-Spain	http://c4fm.es
Wires-X	Room 27187
YSF 27187	ES-WIRESX
YSF 22401	EA-C4FM-Link
EUROPELINK	24
NXDN	214
P25	2140
DMR+	2140	IPSC2-EA-RPTR Server
DMR+	Reflector 4370	All Server
Peanut	YSF-EURO	http://peanut.pa7lim.nl
FCS	FCS004 00
FCS	FCS224 24

Support & news on Telegram: https://t.me/dmrserver

Tips for a successful SOTA (CW) activation

 

I will try to resume and explain here some tips for achieving a successful SOTA CW HF operation. Some of them are sooo ovbious that can be easily forgotten. Others come from my own experience along about 275 activations, almost all of them including CW operation. And remember, any activation will be easier if you carry: antenna, transceiver, charged battery, keyer, notebook and pen(cil)! ;-)

Almost all the information here can be applied for any kind of SOTA activation, no matter if it is on VHF or HF SSB/Data.

As in any SOTA activation, there are common factors to have in mind. These are some of them:

Before activation starts:

• Planning, planning, planning! About trip, hiking path(s), timings, daylight time of the year, wheather, Activation Zone, phone coverage, V/U repeaters, DMR, etc.
• Before starting the trip, at home, check that you have all your radio items, rig, antenna(s), connectors compatibility, batteries (charged), mic, keyer, notebook, pencil, mobile phone, compass, GPS, whatever. Try to make & use a checklist.
• Check carefully the weather forecast, that will lead you to choose the appropriated clothes, shelter, etc.
  
• The same for non-radio equipment: the ten essentials, food, water, backup clothes, shelter, etc.
• Then, with all that information, put an alert on SOTAWATCH. Putting this alert, the RBNhole system will spot you automatically during your activation in any CW frequency you are, and on an interval of -1 to +3 hours of your alerting time. 
• If you are part of any activators community (e-mail, social networks,...), keep them informed of your plans. So do it with family and/or friends. Try to keep your phone GPS activated, it will help to locate you in an emergency.

Once on the activation itself:

Keep always in mind that a SOTA activation is defined by some particular factors. Your security is the key one. Daylight, weather conditions, your physic capabilities must always define how the activation will be. Don't feel forced to operate on any mode, band, time, duration, etc. The arrival time and duration of an activation are just an estimation, not a signed contract. Weather conditions can change, or daylight be sort, so always make the activation fit your security. All this said, begin activating!

Prepare yor antenna, radio and any needed accesories ready to operate. 

Try to put the best possible signal on the air (antenna, power, etc) This will help to be better heard and understood (in case you make QSY, QRT, call for partial callsigns, etc.) Make your calcs concerning power used vs battery duration to achieve it.

Once all ready, spot yourself on SOTAWATCH (if possible). Otherwise, you have the choice of transmitting it on a V/U repeater, and/or ask to be spotted. You can also make it via SMS or APRS. Check them all if necessary. (Remember you have already planned it!)

Make a first CQ call, long enough to be detected by RBNhole. Include the summit reference on it.  This is specially important in case you've been not able to spot yourself in the traditional way. RBNhole will use your previous sotawatch alert to "migrate" and insert automatically this information to sotawatch as a spot.

When the QSOs begin, try to keep yourself calm. The pile-up behaviour will be a reflection of yours. If you cannot copy a full callsign, you can ask for partial calls too. But always calm and relaxed. Chasers are at home, not under heavy rain or winds!

Don't use a very high speed, your signal probably will not be very strong, and you must be clear and steady. 20-25 wpm will be more than enough. This is not a contest and your goal is making as many QSOs as possible, but 4 are enough.

Try to adapt your speed -if your rig allows it easily while making the QSO- to the correspondent's. If you cannot, leave longer spaces between the characters to make your transmission easier to be copied (Farnsworth timing)

Mantain a constant rythm , i.e. always end your QSO with: [callsign] TU 73 DE [yourcall] K. This will help the chasers to follow your operating style, and make more and faster Qs. 

Never answer "out-of-turn" callers. If you call f.i. "AB1?", never answer a "BC2..." op. This will make the pile-up uncontrollable. Keep on calling "AB1?" until being answered, or start it again making a short CQ, calling "QRZ?", or so.

Think before answering "tail-enders". Otherwise, the chasers will keep calling long time after your call. 

Try to listen a bit out of your transmitting frequency, say 50-100 Hz up or down. This makes your callers spread a bit, your frequency will be more clear, and you will be able to listen different tones easier.The chasers will be soon aware of this technique and use it. Better for you all. 

Try also to keep your chasers informed in case you must stop (QRX) your operation to  change something (antenna, links, batteries), troubles with the wheater, falling elements, eating or drinking, explanations to visitors on the summit... Don't dissapear from the air without any explanation (if you can, of course). 

Keep sending spots when you change the band or mode in the way already explained

Depending on how many people is calling you, repeat your callsign and summit reference acordingly. Sometimes two different activators can be on the same frequency, or your summit being spotted wrong. It could be done every 3 QSOs (if only a few are calling) or every 10-12 calls. If you control the pile-up right, up to 2-3 Qs per minute can be done.

Once the number of chasers decreases, think on making several more calls and make QSY, but try to stay on the band at least for 10 minutes. Chasers not always are instantly ready to answer you once the spot is sent. Some QRP chasers also use to wait until the bigger stations end to call you. Give them a chance to work you as well.

Keep Always In Mind: How long you can remain operating depends on your safety, weather conditions, temperature, estimated time to go back to the car, physical condition, etc. Your are taking all the risks, so you, and only you, decide it!

Try to follow the same habits along all your activations. The chasers will know & use them for working you. For example, start on 20m, then 30m, later on 40m, etc. Use the same freqs around the most used on SOTA activations (could be 14.063, 10.119, 7.034, etc). It will  also gives clues to the chasers about when and where to find you, resulting on a successful operation.

And remember: a failed activation is always better than a risky one. The mountain will be always there for you to come back again. If you are still alive, of course!

All this information is based on my own experience, and probably I forgot and left some important aspects out. So please, don't hesitate to contact me and I shall include them ASAP. Don't forget that english is not my mother language so please, forgive my mistakes.Thank you.

73 de Mikel EA2CW
ea2cw /at\ gautxori /dot\ com