ANTENTOP- 01- 2007, # 009

UR5WCA Balcony Antenna for 7, 10 and 14

SWR at 7, 10 and 14 MHz was near 1:1,1. While two weeks running the antenna on the bands I did a hundred CW QSO with practically of all the European countries and some district of Asia of the former USSR. I have received 569- 599. The antenna works with low SWR at 80- meters, however only local QSO was done. At 18 MHz the antenna has SWR 1:2. For testing the antenna I used a home- brew transceiver made on the base of old Russian receiver R-250 and ATU MFJ- 945E.

 

Modification of the UR5WCA Balcony Antenna for 7, 10 and 14- MHz

 

Figure 4 shows modification of the antenna that increases it performance. Inductors L1 and L2 were coiled by insulated copper wire in 1.5-mm (15- AWG) diameter, spacing between turns is 2-mm. Form diameter is 35- mm (was used PVC tape tubes), numbers of turns are 29, tap from 9 turn from cold end. FSM (Field Strength Meter) displayed increasing of electromagnetic field to 30% compare to antenna without matching coils.

 

Figure 2 Schematic of the UR5WCA Balcony Antenna

Figure 3 ATU of the UR5WCA Balcony Antenna

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