Introduction Amateur radio VHF operating assets - April 2021

VHF operating assets - April 2021

Výhľad z JN88XX na juh
View from JN88XX to the south

During one of the walks in the area, I registered an interesting view from the JN88xx locator. Using the program Dioptra I did an horizon analysis. In the direction to the southeast is relatively close to the hill Chabová, but the main directions seem relatively well open. Altitude is 630 meters.

Because theory is one thing and practice is another, I decided to try the place in a VHF operating asset. I packed the car Kenwood TR-751E, 6-elementovú yagi YU7EF and the necessary details. Unfortunately, a car battery that has not been used for a long time no longer looks useless, so the power supply was provided by two smaller ones, 14Ah and 7Ah batteries.

Already at the entrance to the village of Horná Súča, I noticed snow flakes on the way. Also in place, where I wanted to park the car I was greeted by a mixture of mud and snow. The antenna can be built and anchored without the help of another person by the method of building a mast through a needle, but since I gave YU7EF yagi only to a height of about three meters, so I estimated to tie three anchors and lift the mast. Subsequent calls were already easy.

As the VHF time of an operating asset does not coincide with the time of a race in other countries, so I retuned the band before I started. The Acer Aspire One netbook runs N1MM +. Internet connection, so I did not deal with the cluster or chat.

Netbook s N1MM+ transceiver TR-751E
Netbook s N1MM+ transceiver TR-751E

At the beginning of the race, a serious problem appeared - the TR-751E transceiver occasionally oscillated at a set power of 25W.. Is possible, that it was caused by HF energy from the antenna or battery power. So I switched to 5W, where the problem did not occur.

Connections with such power do not increase easily, so after a slight reorganization of the workplace, after about 30 minutes I try again by 25W. It's better now, the transceiver oscillates only occasionally.

YU7EF yagi have excellent directional characteristics. Clean. This is both an advantage and a disadvantage. Advantage, that it allows you to divert from an unwanted signal, but at the same time it is necessary to rotate the antenna in the desired direction.

Occasionally the sun peeked through the clouds, the temperature was quite tolerable. Only the snowy Chab reminded her, that it is still spring. I did not hear German and Italian stations at all. At least it worked 504 mileage connection with YU7ACO and several Croatian stations.

Directional statistics of connections in VHF operating assets
Directional statistics of connections in VHF operating assets

It was only in the end 44 link, but a lot of valuable knowledge. So maybe I'll come back to this place again.