LF: F6CNI to night testing a tuned loop TX on MF

["F6CNI - Andy - JN19QB" <f6cni@orange.fr>]

Hi to all.

 

This evening, I’ll transmit to test a single turn loop on MF.

 

• 1 Watt HF TX ;
• Mode WSPR 2 and perhaps  also OP 8
• Loop description :
  • Vertical position, top at 11 meters, bottom at 1 meters over ground ;
  • Each side wire is 7 meters long ;
  • One single turn copper wire 10 mm diameter ;
  • Maximun lobe NW / SE. Note : at 600 km, the front / side lobe is about 6 dB ;
  • Impedance 0.21 - 113 j ;
  • Current wire 2.0 Amperes for 1 Watt output TX ;
  • Top loading using a 3C90 tore isolated transformer ;
  • Base tuning with a variable in parallel with a fixe capacitor. Total needs around 3000 pF of total capacitance ;
  • 50 Ohms coaxial to the TX ;
  • Minimum SWR at TX when the CV is well tuned : below 1.3 / 1.

 

Best 73.

 

Andy. F6CNI