Ready again to receive VLF with my new loop. At the moment the antenna is located on the roof under the TX antenna for MF-LF.
The preamplifier circuit comes from the easyloop of VLF.IT with an OP27 and few others components.
The antenna is composed by 32 turns of 0.15 mm dia. for a total lenght of over 200 meters. No screen has been applied around the wires.
Power supplied from a 12 V battery the signal goes down to the station by a little dual coaxial cable for submergible cameras (video+PS).
Just before the input to the audio board I’ve used a 50:600 Ohm home made trafo to optimize the signal.
This solution give me less noise and more signal.
Next step will be to insert the GPS to one of the audio channel to discipline by Spectrum Lab the audio board and get a stable and precise frequency.
Under here an image of this afternoon.
I still have an unknown noise on 10KHz.