First activation - March 29. 2015.
Mt Avala (YUFF-006) is one of Belgrade landmarks, along with the TV tower near its top. Although Wiki and media say it has 511 meters, the topo maps say 506 meters, so the latter was accepted as official height in SOTA.
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| By Djidash (Own work) [CC BY-SA 4.0 (http://creativecommons.org/licenses/by-sa/4.0)], via Wikimedia Commons |
Avala is my closest SOTA summit. It is less than 20 km away.
At the end of March I finished building my basic SOTA equipment: a MTR v2 rig designed by KD1JV, and my clone of ZM4 antenna tuner. The wire antenna was cut and prepared in the morning of the activation, on March 29. I decided to make an antenna for 14 MHz, a quarter wave vertical with 2 elevated radials, since I had excellent results with this type of antenna in the past (on 40 meters).
At the end of March I finished building my basic SOTA equipment: a MTR v2 rig designed by KD1JV, and my clone of ZM4 antenna tuner. The wire antenna was cut and prepared in the morning of the activation, on March 29. I decided to make an antenna for 14 MHz, a quarter wave vertical with 2 elevated radials, since I had excellent results with this type of antenna in the past (on 40 meters).
We parked at the parking are at the lower peak, at the base of the TV tower. There is a 500 meters walk to the top from there.
On the top of Avala there is a Monument to the Unknown Hero, a WWI memorial. The area around the top is a park with paths leading to the monument. I guess the park should be kept free of leisure activities, including radio, so I decided to find an operating place elsewhere in the activation zone. The park and the top are encircled by a road (closed for vehicles) just some meters above the activation zone limit. Apart from the circular road itself, the only remaining flat areas within the activation zone are a small picnic area, a parking in front of old Hotel Avala and the hotel building itself, and a flat area behind some souvenir kiosks. Apart from the big TV tower on the lower Avala peak, there are two communication towers on opposite locations along the circular road.
I chose the picnic area for my activation location. It very close to one of the communication towers. Since it was my first portable activity ever, it took some time to untangle the wires and rise the antenna. I could not tune the antenna properly, the LED on ZM4 was only slightly diminished. I think I read somewhere that this might be caused by strong signals from the nearby communication tower - the antenna picks them all and disrupts the expected operation of the resistive bridge. Anyway, I tuned the antenna the best I could and hoped for the best.
I am not a good cw operator and have been long time off the air, so keying mistakes were abundant. Most of all I kept forgetting to sign /P. Some mobile network QRM was heard, but not too much. Soon after my first CQ, first contacts were made with DJ1PQ and DL2KAS. And after that - nothing, nobody was coming back. I thought that I might have damaged my transmitter because of unmatched antenna. Finally, after some retuning and more cqing, the pileup started. During next 25 minutes, I worked 24 stations more (26 in total), and then the pileup stopped. That was it, not too bad for a first SOTA activation.
Warmer weather was forecast for following Saturday, so I decided to make an early morning activation, this time on all bands (i.e. on 7, 10 and 14 MHz since these are the bands my MTR v2 operates on). During the week I built my portable cw paddle, and started building a second antenna. I decided to try a doublet for 7 MHz and above, fed by 450 ohms home made ladder line. Due to other commitments, the antenna building was again left for the morning of the activation, and it took much longer than expected, so instead early in the morning I took of to Avala at 11 AM.
Despite sunny weather, there were not much visitors at the top, so I decided once again to erect the antenna in the picnic area. I also inspected an alternate location, a small flat area behind the souvenir kiosks, at the same elevation. Maybe next time I will go there since it is uninteresting for visitors, always unoccupied and further away from the communication towers.
I had much more problems this time while erecting the antenna. Thick and heavy wires kept pulling down the fishing rod mast and getting tangled in nearby trees. Same as a week before, I was using a 12V SLA battery, so my MTR v2 was giving almost 5 watts on all bands. I tuned (again with difficulties) on 7 MHz, and S54X came to my call. Just as I was finishing the exchange, the antenna decided to come down, so I ended the exchange with the antenna mast in one hand, the other hand keying qrx 5 ant dwn.
5 minutes later I secured the antenna and continued with 5 more qsos. I jumped quickly to 10 MHz, but nobody there came to my cq. I had not much time left so moved further to 14 MHz (latter home I saw I have been spotted by rbn, so maybe I should have waited some more time on 10 MHz). After 6 more qsos on 14 I had to call it a day and move on to arrive on time for my nephews birthday party.
Well, after this activation I must say I am not impressed with the doublet. I am using one at home (2 x 21 m) with great success, but that one is sloping from a 30 m high building. This one, attached as an inverted V on a 8 m fishing rod, is nothing more than a cloud burner, in my opinion. Besides, I made it from 1 mm2 PVC insulated electric wire, and it is quite heavy for the cheap fishing rod I am using as a mast. So I am considering again resonant monoband quarter wave verticals for 10 and for 7 MHz as my next antennas...
I chose the picnic area for my activation location. It very close to one of the communication towers. Since it was my first portable activity ever, it took some time to untangle the wires and rise the antenna. I could not tune the antenna properly, the LED on ZM4 was only slightly diminished. I think I read somewhere that this might be caused by strong signals from the nearby communication tower - the antenna picks them all and disrupts the expected operation of the resistive bridge. Anyway, I tuned the antenna the best I could and hoped for the best.
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| My first SOTA activation, 29.03.2015 on YU/CS-043 |
Second activation - April 4. 2015
Despite sunny weather, there were not much visitors at the top, so I decided once again to erect the antenna in the picnic area. I also inspected an alternate location, a small flat area behind the souvenir kiosks, at the same elevation. Maybe next time I will go there since it is uninteresting for visitors, always unoccupied and further away from the communication towers.
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| My operating position |
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| Operating at YU/CS-043 |
Well, after this activation I must say I am not impressed with the doublet. I am using one at home (2 x 21 m) with great success, but that one is sloping from a 30 m high building. This one, attached as an inverted V on a 8 m fishing rod, is nothing more than a cloud burner, in my opinion. Besides, I made it from 1 mm2 PVC insulated electric wire, and it is quite heavy for the cheap fishing rod I am using as a mast. So I am considering again resonant monoband quarter wave verticals for 10 and for 7 MHz as my next antennas...
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