Having modded my Ten Tec RX-320 for VLF/LF (for no good reason other
than I was in there anyway), I am looking for a cheap and easy low low
band antenna. Two miles of wire is not practical for my QTH. Also,
big loops are problematic. So I am considering antennas using huge
ferrite bars and reasonable wire lengths.

In particular, I am interested in the antenna entiled "Shortwave / AM
/ Longwave Radio Booster" shown at:
http://www.stormwise.com/vfr12cproject.htm

I would use the direct connect option, since my radio has no internal
ferrite bar for coupling to.

(1) Does this make any sense at all?

I would put the turns on a bigger pipe and slide the ferrite into the
bigger pipe. I am told that you can "fine tune" by sliding the
ferrite bar. I am not sure what is being fine tuned, except maybe the
inductance to get resonance with whatever cap is in the circuit.

If it does make sense, can I get this to work from 10kHz to 550kHz?
10kHz to 1500 kHz?

The vendor thinks so, but he is selling ferrite bars -- the bigger the
better. He is recommending the 24" monster, with 300 turns and a 1 uF
cap. However, using 27 ga magnet wire, I only need 5" to get 300
turns.

(2) Which ferrite bar should I use -- 12", 24" or 36" -- to get the
result I need without overkill? See table at:
http://www.stormwise.com/vlf.htm

(3) Is there somthing I can read that will provide some guidance as
to number of turns, cap value and expected frequency range?

Ken KC2JDY
Ken
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