Longwave/mediumwave square loop

Pushed by the achievements of authorized HAMs using the 500kHz/600m band, I decided to rebuild my multi-turn square loop for long/medium wave.

I played with it maybe 10 years ago but I still had all parts laying around. It is composed of:

• 4 meters of computer flat cable, 26 wires (probably), soldered "shifted-by-1"
  
• two wood sticks 1 meter each
• one variable capacitor (whatever you have at hand, even a trimcap will do)

Initially I will hang the loop on the shack window, hoping not to catch too much noise from the building, starting from the shack CFL lamp.

The loop will be 25 turns in parallel with the capacitor, coupled with one full turn loop to the receiver. Probably this configuration has a high impedance, about 2kohm (how to measure it? my MFJ259 doesn't go that low), so I might also try a step-down transformer with a surplus toroidal core salvaged from somewhere.

If the loop will not pick too much noise I will try to add an active amplifier in between the antenna and the receiver.