Tuesday, December 31, 2019

Stew Perry OK6W from OL7M





Pavel OK1MU is enjoying Christmas holiday also at OL7M contest QTH. Expect the 160m DXing he run also Stew Perry Top Band Challenge.

There is his 3830 post:
One of the most interesting contest of the year. Many friends on the air and good conditions towards the NA. Worked 300 x NA and 16 x JA. Used IC-775DSP, 40m Vertical and 8 BVRGs. Thank you for all the QSOs and see soon you during ARRL RTTY Roundup. Happy New Year! Pavel, OK1MU (OK6W)

Our new Top Band vertical

 SH5 statistics:
 NA QSOs

Call: OK6W
Operator(s): OK1MU
Station: OL7M
Class: Single Op HP
QTH: Policko
Operating Time (hrs): 14
Location: Northern Europe
Summary:   Compare Scores
Total:QSOs729Total Score5,669

Sunday, December 8, 2019

Radio Astronomy 8.4 GHz, part 1: building antenna





It was my childhood dream, EME and radio astronomy. I took long years and now I do have room and rest parts but missing time :) This winter (2019) I have decided to do something. On the wine with my friend Lubos OK2BEN we have started to speak about mechanical parts. He sent me full mechanical drawings after a few weeks :) What a service. Also with the full list of parts so I just could order it and start...

The mechanical system is based on nice HW by Marek OK2DL

A few years ago we got nice 4m dish from NEC. It has got f/b = 0,25. It is not very usable for EME. I have decided to learn more about mechanical systems and good RX from the space. This is great possibility.




So I bought welding machine and started learning :) There is a lot of to improve and learn...



Thanks to my girlfriend Lucka for help :)



Franta OK1CA visited me one day and we spoke about satellites, EME and also 8.4 GHz. He offered me his septum feed design. I bought all parts for two pieces and found one Sunday. Result was one feed which I sent to Franta for tunning. Thanks a lot Franto! He allowed me to publish his designe: HERE you can download it.

I found small piece of CuAg sheet and started.




And there are results for port isolation and S11:


 Photos from Franta: Kumar for dish

Tuesday, November 26, 2019

CQ WW CW 2019 SOSBs: OK6W, OK7W, OL0M





We had a lot of work before contest on RX antennas, Top Band vertical etc. Finaly a few hours before the contest we were ready. Just 20min before contest start we lost tubes in OM-4000 (second time)...

We now do have ready 9 beverage antennas including 2 wire Bi-Directional one and 2 el end-fire to NA. Adding RX CMCC (common-mode current choke) helped and we feel lower noise from beverages. All HW is from www.QRO.cz :)


 Pavel OK1MU as OK6W SOSB 80m HP
 160m Top Band vertical tunning box
Beverages :)

3830 notes from PAvel OK6W:
Fantastic contest and great fun for 42 hours, which I spent on the band. For the last 3 weeks we have been working very hard on QTH to prepare all equipment for 160/80m, which proved to be crucial during the contest.

Btw, In 2016 I was also on SOSB80m HP, but the conditions for the directionforf the USA were poor, and excellent for JA. This year it was quite opposite. I did great number 640 x NA (previously only 300 NA) and 138 x JA (previously 184 JA). Amazing was the number of BY, which is 22 in the log and also 7 x VK on 80m is good from OK land.

Used IC-7800, OM Power and Sloping dipoles with 4SQ hybrid, antennas multibeaming and Rx switching. Good improvement on RX antennas with additionals CMCC (common-mode current chokes) and 2el end-fire beverage to NA. All parts from www.QRO.cz . For RX used 9 QTF BVRGs, totally over 2400 meters... 
My greatest thanks go to our technical guru Jan OK2ZAW, for complete technical setup and eating service during the contest!

Anyway, it was a beautiful contest that I will remember for a long time. I really appreciate that we managed to break the 15 years old country record held by a nice friend and a great contestman Jirka, OK2RZ!

Thanks a looooot for everybody who calling me, without you, the CQWW would not be what it was !

Pavel OK1MU/OK6W