Hi Mikebg.
You are absolutely right. I have past experience in the construction of an amateur on the 4MHz filter ladder with 100Hz bandwidth and less. At 32kHz easily get smaller bandwidth, the more crystals are exactly the same watch. What about modulation A2 ?
Vaino Ronk AIR uses second RX signal from antenna as reference signal , a brilliant idea + todays software that gives a strong instrument.
I hoped to check the simplest method. Lighting treasure chest only to the GND, a simple receiver - preferably with a vertical antenna ferite. Then I have a minimum of receipt by the AIR and directional reception of the order. SPECTRUM LAB is the program straight from the VLF.
Ideally, it was simple, easy and fun, small and cheap. Perpetium mobile not yet.
Is this a useful?
http://www.stormwise.com/page28.htm
Best regards