[Milsurplus] Ferrite cores and 16Khz reception

[Hue Miller]

TV type flyback transformers have suitable permeabilities for VLF loops but not a convenient dimension. They are generally glued together in two halves and one half makes a good loaded inductor with fairly high Q.Getting resonance near those frequencies takes lots of high Q capacitors and many wire turns. 
 
Palomar Engineers make a VLF loop that goes down to 50Khz. Perhaps it could be modified to work lower. 
 
In the mid 60's I installed inductive loop wireless paging systems and it was normal to copy NSS in Jim Creek in downtown Toronto with a small resonant reed vest pocket receiver at 16Khz. 
 
Ralph 
VE3BBM  
 
Ralph- VERY INTERESTING. The inductive loop pagers, were they tuned systems, tuned to an LF
frequency, or broadband audio responding? What did the VLF signal sound like?  ( NSS actually
Navy in Annapolis, MD, USA - i believe.  Jim Creek near Oso, Washington was station NLK but
when i heard them in the 60s they were keyed out of San Francisco hence sent call as 
NPG/NLK.  At least i think they were keyed from SF; i don't know this for a fact, i just realized,
but it made more sense to me than NLK keyed by Jim Creek. )
 
The TV flybacks work at 15.75 kHz and i've long thought there was some possiblity there.
You would have to break the closed magnetic loop of the ferrite frame, tho.
-Hue Miller 
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