Re: [IRCA] Recent logs from Moody, Texas

["Gil Stacy" <gilstacy@xxxxxxxxx>]

James,
Wire size is not critical.

Assuming you have good ground, I would look to the toroid/windings you are
using.

The absence of good ground affects directivity and not the ability to hear
lower in the band.  My two ewes perform excellently and I could send you a
sound clip of 780, WBBM, Chicago and ZBVI, Tortola (BVI) being toggled back
and forth between the ewes.  WBBM is on the 35 degree ewe and ZBVI on the
118 degree ewe.  In the one minute clip, both stations id.



Steve Ratzlaff and I have recently had an email discussion on cores.  Using
his HP spectrum analyzer, he has tested cores made on FT114-J and ferrite
beads, FB77-6301.

I had sent him two pairs of the beads for use in a Gary Breed (K9AY)
designed mini-binocular core, made by gluing two of the small beads together
in binocular form, and winding 3 and 9 turns.  On Steve's FT114-J, he used
11/33 turns.  Here are his results in the testing which was done with two
transformers of each type back to back. (He tested on wide range of freq. ,
HF to LW, but these are his MW results) The gross loss was divided by two to
reflect the average loss per core:

FT114-J:

530 kc  -.1dB

1000 kc -.15

1260 kc  -.2

1730 kc  -.25



FB 77-6301 mini-binocular

530 kc  -.35 dB

1000 kc -.4dB

1260 kc  -.4 dB

1730 kc  -.05 dB



In the testing, Steve discovered that the toroid transformer, for best
results, the short winding must be on top of the longer winding and not on
opposite sides of the toroid as some have suggested.
The mini-binocular would be improved by more windings on each.  On longwave,
the toroid's performance was better by a larger margin. Hopefully Steve will
comment on his testing which is ongoing.
73, Gil NN4CW
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