SM6BGP on 500 kHz.
                  Return to index page

Some pictures of the Double Inverted L-Antenna at my home QTH in Kinna/JO67IL
Simple antenna layout with the little coil-house in center of the picture. The ground plane wires are of varying length adapted to the size of the house garden. A lot of metal is digged into the ground for better take off for the radio waves.
This antennas fundamental frequency is 1260 kHz without coils and capacitors.
The little coilhouse where different frequencies are tuned in.
Coil for 136 kHz takes form.
Coil for 136 kHz ready and dimensioned for single wire inv-L.
Impendance tranformer and cable switch.
Impendance tranformer.
Earth connections via copper plate.
Antenna connection outside the coil house.
Handy little coil house for antenna measurements.
When to work at 150 meter I add some capacitance.
136 kHz coil at top, with less turns for double L-antenna.
Antenna connector outside the coil house.
This picture shows data from the fundamental frequency without accessories, 1261 kHz.
This picture shows data when the big long wave coil (2.225 mH) is added, but no transformer.
This picture shows data when the variometer is added with maximum inductance, 679 uH = 233 kHz.
This picture shows data when the variometer is added with minimum inductance, 119 uH = 519 kHz.
To work on 472 kHz I have to adjust the variometer to approximately 130 uH and of course use the transformer.

This picture shows data when the variable capacitor and transformer is added, approximately 229 pF of capacitance.
The antenna seems to work very well also at our 150 meter band!

Picture of my little woodie, with just one EL84 tube and a modulation transformer from an old radio.
Just for fun I use this little wonder on 1945 kHz with AM modulation. Output is about 3-4 Watt.
   



SM6BGP - Gunnar Ivarsson, Andra Hedakersgatan 16, SE-511 58 Kinna, Sweden
Member of SSA and SK6RUD - Radio Rud of Sweden

 INFINEON - SPW47N60C3 - MOSFET, N, COOLMOS, TO-247
  2010-2019 SM6BGP