Monday, October 14, 2019

OMFF-0725 Dubovy Vrsok / Oak Hill

Bike trip in lovely sunny afternoon, 28km total, all equipment in small backpack. 49 QSOs in 50min, 40m + 20m CW, thanks for calling me. Used FT-857-light, LiPo pack 3S 5Ah, 70W, linked dipole.
73 / 44 / Ahoj

OMFF-0057 Javornicek

Started at 15:45, all tourists were coming already back in opposite direction... I lost my headphones somewhere and had to use small ones. Readibility of signals was not good, don’t know if it was due to bad headphones or conditions, sorry for those who I did not hear. Nevertheless, optical conditions during sunset blue hour were outstanding, pictures taken by lens camera.
Thanks, 73 / 44 de OM2JU

Tuesday, August 28, 2018

2018-08-20 South Moravian SOTA activities

We, members of OM3KII radioclub spent nice week together in recreational area near Skalica, which is not far from Czech border.

Together with my son OM1ATU, Ondro OM4DW and Brano OM1BD we decided to spend one day visiting flat summits in south moravian region. I must admit, they are only 1 point summits however the area was alway very interesting.

Saturday, March 10, 2018

2018-03-03 Winter SOTA activity - Velka Javorina

Preparation for 1. Subreg. contest of OM3KII on Velka Javorina (locator JN88UU) went smoothly

It was nice clear and sunny day, however the temperature was below freezing point. I decided to pack out my SOTA equipment for shortwave and try some activity on 20m and 40m

Monday, February 12, 2018

2018-02-12 Loading coil for short multiband vertical 10m-80m

Building my new multiband shortwave vertical for WFF (Worldwide Flora Fauna) operations.

Inspired by N1LO shortened mobile vertical:

Learned that very critical for efficiency is loading coil - must be airgap construction in order to reduce stray capacitacne and dielectrical losses. The coil shold not be “narrow and high”in order to maintain high Q.

1. Designing and printing the coil support on 3D printer, material is PET. Consists of top, bottom part and 4x comb sticks. All plastic parts are assembled together and form one piece.

2. Preparing Cu wire, diameter is 1.7mm, wound on plastic pipe of 10cm diameter and taken down from the pipe.

3. Cu spirale is easily wound on coil support. Wire pressed/clicked into openings on perimeter and fixed at both ends. All goes smoothly, I’m missing only a few last windings so now the antenna resonates at 4.3 MHz. After adding missing windings it should be OK also for 80m.
Next version of support will need to be stronger as middle of the coil is now slightly shrinked by pressure caused by windings.

2018-02-11 SOTA OM/TT-002

Marhat (OM/TT-002), closest SOTA summit to my home, only 2 points. However in winter time there are additional 3 bonus points counted as the elevation is 748m asl. Good reason to start trip on sunny Sunday afternoon.

Pictures were taken by iPhone equipped with Circular Polarization Lens attached to it with clip. Bought on eBay.

Tower on the summit. I was transmitting from bottom as the wind was rather fresh

Sun is setting down. Picture taken from top of tower, my hands were freezing

2018-02-08 SOTA OK/LI-010 Jested

Jested is the highest mountain peak of the Ještěd-Kozákov Ridge near Liberec in the north of the Czech Republic. From the summit there are views into Germany and Poland.

On the summit is located spectacular tower in hyperboloid shape, architectural treasure of Czech Rpublic designed by Karel Hubacek.

Unfortunately it was fog on summit and freezing, fortunately there is restaurant and bufet with warm meals and drinks.


Linked dipole for 7MHz

Alien statue (left)