Tuesday, September 29, 2020

 CQ WW RTTY 2020 as OL9A SOSB80

I am quite busy last months and I was decided to work and do not run contests a few weeks ago... But than I have changed idea and wanted to finish some old projects: 80m single band PA and 5el wire yagi. PA was almost ready but I found problem with the low voltage for G2 and this could be a lot of IMD than better to leave it for next contest. And thanks to big help from Olda OK1YM, Pavel OK1MU and Jarda OK1XUB we could finish 5 el Wire yagi for 80m for the first testing in the contest. Also BIG  thanks for their help not only with beverage antennas. I could have it only for this weekend and WX was bad - a lot of rain :( We added one more beverage to NA on Saturday. 

And how about the contest. Well, quick look at aurora numbers and I could imagine how bad it could be :( Contest starded and there were no pile-ups. A65DR was between fisrt, thanks Paul, nice signal! US station with very very low signals and what more - coming from 260 degrees beverage! So my 2 el End-Fire to 315 degrees was totaly for nothing :( Last time (2016) I made 125 US during the first night. What a nice number compare to this year one. At the end of the first morning I was missing around 70 QSOs. What can we do, it is almost the same for all in the contest. Time for short sleep and than work on one more beverage. Conditions to East looked better. I could easy work 7 JAs. Surprice in numbers of VU and YB, thanks for 4 and 4 QSOs. I think I missed some DXCC which called me, but I was not really sure for QSO and did not log them, like: P4, LU, 2 x California etc. Nice highlight were VK5ARGRobert T6A with S7, Hasnad AP2HA with S8 signal and ZM4T in 6 UTC via the Long Path but with signal S7 :) 

Totaly made 119 US, 9 VE, 1 VK, AP2, 177 DL etc

I could not have time to compare 4SQ-8DIR and 5el wire yagi in EU and East Coast, maybe next time. Anyway signals in the West and North EU were very strong.

We also found some time for the ground work. So more than 200m of trench for new cables and two holes for another UHF antennas - 8.4 (10) GHz dish and 16th H+V yagies for 70cm EME.

Final score: 1029 QSO   2190 Points  19 Zones   68 DXCC   26 States  

Score : 247 470

5el Wire Yagi

Monday, September 21, 2020

 40m 4el Yagi - part 5: ERECTING

This is the biggest project at OL7M after the H-frame 4 x 6 el G0KSC system for 10m (link). Started about 10 years ago. Jiri OK1RI designed it in 2012.

This 4 el 40m Yagi project is over thousand hours of work. BIG thanks to Jiri OK1RI for many hours of designing. The result is incredible: designed results are the same as reality! Despite the facts that there were a lot of unknowns. We also have to thanks to Father of Jarda OK1XUB for mechanical designs and all consultations, Pida for climbing and many many other who were participated in this big and long project.

There are some parameters:

Boom length:                    19,05 m / 62,5 ft

Boom weight:                    130 kg - special dural triangle 70x70x70 cm

Longest element:             23 m / 75,46 ft

Elements weight :            190 kg - dural - 14 tubings, biggest diameter 100/5 mm

Tower height:                    36 m / 118 ft - triangle 80x80x80 cm

SWR:                                  less than 1:1,2 (7,000 to 7,200 MHz)

With 5m of coax

All posts about this project are there (link).