It stopped raining exactly, when it was convenient. It's raining all the way, but only easily. But the sky is pouring out in front of Myjava. All the more surprising, where the blue sky shines through from Sobotišť. Apparently it's blowing, but the road is partly dry. It is wet and muddy on Černecki vrch, but it's not raining. Glory!
It's unbelievable, how many antennas can fit in a car. This time I'm driving 4x 5-elementov DK7ZB yagi and 2x 8-elementov DK7ZB yagi, which I end up not using. But I'm getting ahead of myself. Building the first antenna system is easy even in strong winds. However, building a second mast is not. I wanted to try a thinner extendable pole held by a bike rack and topped with four anchor cables. But the force of the wind was such, that the mast wanted to topple even without antennas. So I preferred to disassemble the antennas and mast again and decided to go for one antenna.
As I had considerable time to spare, so I also checked the beacons OK0EWW and OE3XTR. Everything works. So I start on time. team, that the Alpe-Adria UHF Contest is taking place, that's what it looks like, that there are fewer stations on the band. On the other hand, there is a lot of interference! I can see Draha for a few kilometers OM3CQF. However, the interference does not come from the neighboring hill, but from 40 kilometers distant Považské Inovec, where is laco OM4AGW.
You will read:
Comparison of signal strength
If we take the calculation of radio signal propagation attenuation in free space: Au = 20 x ( – 4.622 – log f – log L)
OM3CQF 15W + long F9FT antenna, distance 7 kilometers
- attenuation of radio signal propagation in free space -92,5 dB
- +42 dBm power + 13 dB antenna gain -92,5 dB propagation attenuation + 14 dB antenna gain = -23,5 dBm
OM4AGW 100W? + antenna system 18dBd?
- attenuation of radio signal propagation in free space -107,6 dB
- +50 dBm power + 18 dB antenna gain -107,6 dB propagation attenuation + 14 dB antenna gain = -25,6 dBm
It means, that the OM3CQF signal is o 2 dB stronger and yet does not cause such problems in the receiver.
Fluctuating VHF PA
Moments alternate, when I can't hear stations for moments, when I hear very well. A successful sked with Robert will therefore be surprising I1BPU at a distance 780 kilometers! He also calls for him for a while I3FGX and IK4GNG.
I am looking for directions from where there is the least interference. A successful sked with OM0AJ from KN09. Jano only has a 7-element DK7ZB yagi antenna and 50W. However, the line between us is interwoven with hills. The bounce from the smaller plane also helped. He is followed by YO5OHB from KN17.
Despite the antenna being turned differently, I can hear the call YU7ACO from KN05, what is above 500 kilometers. He will surprise Lojza OM3WAN, which I have not yet done in VKV PA. By connecting with SO2V allows the relatively rare JN87 locator is added, and the neighboring JN97 has been "colored" by HA2NP. After a long chase, the connection with 9A3SM. Big kudos to big-gun HG1DRD – Tamász came to my request for a sked!
Thanks to the filters in Marc's great program DO5AMF for chat via KST, I notice SO7M. He suggests sked on 144,300 MHz. Not a chance… but I heard him there for a moment. I try to pull it on 144,394 MHz and it really works! The only Polish station, from the KO00 locator.
Already during the contest I noticed an unusually high number of stations from JO60. I have up to eight of them in my log. VKV PA is already ending, when I receive a message from OM0AB. That's what I asked for last week, that I would like to try sked. Jožko did not forget and so we threw ourselves into it. We were putting the connection together 6 minutes, because there were only a few smaller planes on the route. After all, bouncing off a large plane is something else: it is much stronger and longer. Reflections from small aircraft last only a few seconds and are not enough for the entire connection. But it worked, Jožko tried to take my locator for a long time, but we were not lucky. It's at the end 104 QSOs to 29 locator squares, 10788 points.
The contribution of points from the north-west direction is unusual:
