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Click for Kinshasa, Democratic Republic of Congo Forecast

Tuesday, April 10, 2007

50 Mhz first steps

in 9Q land...

Grid Locator : jI75PQ

4° 19’ 39’’ S - 15° 16’ 31’’ E

Only CW Mode - earlier I will try JT6M mode

Running March 2007 with the information of Gus 9Q1D and in forecasting of the opening of this band planned for the end of March. I began studied the possibilities to be able to activate and be ready on this band.

I had a transceiver but not any antenna!
Not easier in Kinshasa to find a aluminum pipe as necessary to look for in the city and the scrapes market during several days of the pipe tips of any diameter and often in bad condition!!!!

So. After investigation … I decided to built a vertical.
As having found some alu pipe more or less correct, I constructed a 3/4 of lambda therefore (4,50m long and radials of 1,50m) to begin a little monitoring and to see what it could give.
An opening made itself toward April 04 and I could make a dozen of QSO with the south of Europe.

Picture of homemade aerial 50 mhz vertical and 3el yagi

In view of this beautiful opening, I decided to built a new small beam 3 el following DK7ZB, DL1GNM design, (see diagram below)
Excellent site of 50 Mhz antenna design at:

9Q1EK and 9Q1TB
(Red face is due to the sun… 43° Celsius when 3el installation. Hi!!!

The only difference is the gamma adaptor of my side and especially the aesthetics that is less beautiful of has it my strange pieces of pipes !!!!!
Seen at 13m of height , it doesn't see itself, hi!! And the main, it is that it is well adjusted and that it" works "…

The signals are sometimes as loud as on my vertical, most of the time about 1.5- 2 S-units upper. For real DX the Yagi outperforms the vertical of course...
I find signals outside the Yagi-direction. Not having a rotor for my beam. it is fixed to the north direction. I am able to hear some signals in other directions with the wrong position of the Yagi.

3-Element-Yagi with 1,90m-Boom
Element Element-position Element-length Element-length
Ref 0 mm 2970mm 2974mm
Rad 600mm 2820mm 2820mm
Dir 1 1850mm 2654mm 2666mm

Short data: Gain 6.4dBd F/B 20dB
bandwidth 500KHz (49.9-50.4 MHz) at SWR <>

In red, the curve of my 3 el built with aluminum pipe 22mm diameter
and gamma adaptor..

Fortunately or unfortunately my QTH is located in the zone of Trans Equatorial Propagation (TEP). Propagation across the equator, but largely along the TEP zone, can produce very strong signals, such as zigzagging north and south in the short term, but generally moving along in an east-west direction

Please see excellent article of J. Kennedy K6MIO about
50 MHZ F2 Propagation Mechanisms at:

For the meantime, since 3 weeks two beautiful openings presented themselves, I could make about hundred beautiful contacts with southern Europe. I hope that it is going to open up more soon to the north of Europe.

Since april 04-2007 the best distance is : 6349 km

04 April to 30 April 2007: 19 DXCC Contacted

I am often on 50.102 and Gus 9Q1D on 50.107. We keep 5 or 6 KHz not to be disturb between us.
Finally with these antennas and 200w RF, I hope to be able to hear you on the" magic band ".

73's of 9Q1EK - VE2EK. ZS1ii