info on the K9AY loop
Listening test and other observations
How to make your own K9AY
The importance of good ground
How to place wires best
of the KPAY
wires giving more gain
By Andy Ikin
K9AY web group, October 2, 2000
I have been experimenting with some loop configurations suggested
by Johan Bodin a few months ago.
Without going into lengthy detail, one configuration consisted of
two loops mounted at right angles connected in series.
To my surprise I measured a 5/6dB increase in gain over the normal
K9AY config. As a co-incidence, an e-mail from Gary was forward
to me, giving details of a 6dB increase gain using a two turn loop
with a resistive plus reactive termination.
Therefore, I had to see if a single loop of two turns would work
for LW and MW with just resistive termination.
Well as far as I can see, the answer is yes, but only if the turns
are separated to reduce mutual coupling, i.e. using a twin lead
wire loop connect in series only provides about a 2 dB gain increase.
Separating the delta loops by 1m at each end of the loop i.e. two
poles at each end. The loops cross at the apex. This provided the
5/6dB gain increase.
The only reason I can explain for this increase in gain is that
the 450-50 match xmfr is not optimised for LW/MW. Hence raising
the antenna impedance with two turn loop provides a better match!
So the experimentation continues.