How important is the matching transformer on a Beverage? I am not a RX
antenna guru, I only have installed simple temporary contest Beverages
any place where I could hang the wire in desired directions.
John KK9A
jimlux wrote:
On 1/22/20 1:18 PM, VE6WZ_Steve wrote:
Thanks Jim!
I didn't look at the Fair Rite catalog, but yes…its there on page 8.
I am using 73 material Binocular cores.
The temp. coefficient for 73 material is .65 % per deg C. My temp
change is about 50 deg C, therefore the permeability will change 33
% !!
That seems like a decent amount.
Go to page 28, and there's a curve of properties vs temperature. It
looks like mu is 1500 at -40C and 2100 at 0C (that's at 10kHz, where
mu'' (the loss) is very low.
The impedance at 10 MHz changes from about 80% at -40 to about 90% at 0
to a peak of 100% at 30C.
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