EQUIPMENT: MFJ-1026 used with loop

[wa1ion@xxxxxxxxxxxxx (Mark Connelly)]

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You wrote: 
>
>I think I've asked this question before,but recall no answers.Here it is
>once again.And I apologize for my apparant ignorance when it comes to
>electronics(The MFJ PHASER modifications are too much for me!!) Here is
>the question then.....This phasing Unit is intended for A Long Wire
>Antenna????? What would happen if say..it were used in conjunction with
>a Loop,such as the Kiwa?????? IF this is a dumb question,again,I
>apologize.BUT in my defense,I am a darned good DXER!!It's just that some
>of us don't feel comfortable 'fiddling'around with circuits and stuff.I
>envy those of you that are comfortable with a soldering iron and a pair
>of snippers.
>Tom Messer River Falls,Wisconsin.
>
Tom Messer asked about using a Kiwa loop with the MFJ-1026.
I thought my article had adequately covered the issue of 
diminished interfering-station audio nullability when a 
high-Q source (loop) is used.  It doesn't really matter 
if the loop is Kiwa, Radio West, Quantum, Space Magnet, 
Palomar, d-i-y, or whatever.

Anyway, for the benefit of those who may have missed it, an
excerpt from the MFJ-1026 review article ...

	"Earlier on 26 JUL, I had done a few daytime DX tests of the 
MFJ-1026 from Harwich, MA on Cape Cod.  The first battery of tests 
involved feeding a Quantum Loop into the MFJ-1026 "main" input and 
using the 1026's built-in broadband active whip as the "auxiliary".  
With the loop at normal (i.e. high) Q, audio null depths only reached 
about 20 dB (versus better than 40 dB for carrier).  This is 
consistent with previous nulling scenarios where a high-Q tuned 
source is phased against a broadband one.  You get what sounds like 
a double-sideband suppressed carrier signal.  If the desired DX is 
more than 20 dB below the dominant, you probably won't hear it even 
during stable midday conditions.  Q-spoiling the Quantum Loop (15K 
resistor shunting the L-C tank) increases nullability of "pests" 
maybe to 30 dB, but the loop's usable sensitivity is compromised.  
At night, this is probably a non-issue (except in aurora), but 
during the day you need every bit of signal you can squeeze out 
of the small loop."

For comparison, two phased (untuned) longwires can give nulls of 
40 to 60 dB on groundwave or on lower-angle skywave signals.

73 / good DX ... Mark Connelly, WA1ION