Introduction Amateur radio VKV PA - November 2021

VKV PA - November 2021

Antenna DK7ZB yagi on a mast near the car

With the arrival of the winter months, I started looking for another place, from where it would be possible to participate in VHF competitions. Place, where I broadcast on Vlčom vrch will probably be unavailable in the snowy months. For this reason, I searched the Internet and I was interested in the location near the village of Brestovec, JN88ST.

It is a partially wooded hill, where above the village is a wooden lookout tower Poľana. The search required not only to browse the internet, but also several measurements of field profiles and viewing photos of people, who visited this site. But nothing compares to on-site testing, so on November 21 I headed through Myjava to this location on VKV PA.

Mast construction tip

The inspiration for the construction of the mast is idea OK1FJZ. It can be created in a moment auxiliary arm holding the mast, which is quickly screwed onto the roof rack on the car. It was made of residual material: duralumin profile 25 x 25 mm, L-bracket, Threaded rod and two flat head screws. The principle is clear from the photos.

The second tip is use of pertinax top bearing. It is a pertinax plate with dimensions 10 x 10 cm and a hole in the middle for the mast tube. Holes for four small carabiners are drilled in the corners. Anchor cables are fixed to them. This makes the mast easier to turn and the construction and packaging is also more comfortable.

Code JN88ST, Poľana lookout tower – Brestovec

I'm leaving! The temperature is kept at an unusual + 7 ° C. I knew, that broadcasting from the lookout is not possible. The hill itself has a relatively flat profile, but it is parked in a slight depression. From internet sources, I took a place in the field before the village, which is slightly elevated. I took a look at the four sides of the world after VHF PA, when there was not much to see.

The visual dimension did not dazzle. Firstly, the autumn weather, on the one hand, an uninteresting profile to look at. The view to the west is blocked by a grove, what does he like, where the mentioned lookout tower is located, the profile also rises a bit. The direction to the south looks attractive and I also look to the east to the valley.

Construction of a workplace for VHF PA

I use several improvements for port operation. I started using the hanging table a long time ago. This time I'm except auxiliary arm and mast bearing he also had another antenna, 8-element DK7ZB yagi decomposable into three parts. Such three parts allow the antenna to be carried in the trunk of a car with the rear seats folded down. At the same time, it can be assembled relatively quickly.

Auxiliary arm for mast
Auxiliary arm for mast

So the first thing I push on is the dimension auxiliary arm. The mast is fixed in it, the anchor cables develop. Then I extend the mast without the antenna. Since it is a light type with a height of approx. 5 meters, so the auxiliary arm holds it until the anchors are fixed. So this is the next step.

Pertinax mast bearing with anchorage
Pertinax mast bearing with anchorage

Then I lower the mast again and mount the folded antenna. There's an eyelet on the top of the mast, to which the tensioning cables are attached by carabiners DK7ZB yagi.

DK7ZB yagi in three parts
DK7ZB yagi in three parts

I'm taking the generator to a nearby field and pulling the cable. It's very important, to make the generator work reliably. In addition to powering the equipment, it will help provide heat. Inside the car, its capacity allows me to turn it on small electric heater (400W).

Because I rotate the antenna manually, so i have to keep the window running. In order not to blow inwards, I fasten the car mat to the roof structure. It didn't look aesthetically pleasing, but it helped.

This preparation of the workplace takes a little over half an hour.

Beginning of VHF PA

Workplace OM0AAO in the car
Workplace OM0AAO in the car

I start the race on the R2CW transceiver also with LDMOS PA, therefore with a power of 100W. DK7ZB yagi versus YU7EF behaves a little differently. It's not that directional, but redirection shows profit, which is observable. After about 20 minutes, I throw my eye at the meter of the amplifier - power dropped to wake up level. It is not possible to solve any problem of this type during such short races as VHF PA and therefore quickly i exchange transceiver for Kenwood TR-751E. It has a power of 25W.

When prompted or search?

Point benefit according to individual directions
Point benefit according to individual directions

It's a question, which the radio amateur is constantly dealing with in the race. As it turns out, that the power level also used in races such as VHF PA is higher (in Slovakia 100W, but in other countries more), so I don't create such an attractive signal with 25W, which would mean a continuous benefit for callers. Therefore, it works for me to look for other stations more, working on a challenge.

Be a new location, antenna or both, however, I call noticeably better. I only have to repeat the code exchanged for only one or two stations for the entire VHF PA. So sometimes I also try to challenge, but I'm still getting used to the "sharpness" of the direction 8-element DK7ZB yagi.

ON4KST chat a airscatter

Probably tips, which I published about the use of wtKST whose AirScout-u they fell on at least some fertile ground. I have seen several stations connected. I addressed Slava, OM0AS with KN18 with a request for damage. Until we agreed or found, it took a little longer, but the connection succeeded. The signal was legible. Excellent!

Terrain profile between OM0AAO and OM0AS
Terrain profile between OM0AAO and OM0AS

Not all stations responded to the request. Maybe they overlooked it, maybe they didn't catch up. I tried this way before JN87 and JO60, but these two locator squares could not be logged.

VHF PA results from JN88ST

I had my hands full for the last hour of VHF PA, because the wind intensified and the antenna tended to rotate spontaneously. Hold the mast, writing connections and having a handheld microphone at your mouth would require an octopus. So I didn't do much ON4KST chat and airscatter.

But we also managed to make unexpected multipliers, JN77 whose KN08. Peter OM8ADU he was even audible at the inaccurately directed antenna quite loudly.

Map of locators from VHF PA
Map of locators from VHF PA

He stopped at the end number of connections per number 73 and the number of multipliers per number 22, what after recalculation gives 5544 points. It is the highest point gain, which I managed in VKV PA. At the same time, new and new stations were heard in the last minutes of VHF PA, therefore, probably more could be achieved. I didn't make it this time.

The weather was getting worse. It's not quite pleasant, but it was manageable. In less than half an hour, everything is safely loaded in the car.

I am glad, that I could greet friends on the air and I hope, that we will hear in a month, when VHF PA comes out on 19.December. Hearings!

Diary from VHF PA – november 2021

It will be added after the deadline for reports in other countries as well.