I must add to the praises W0FLS gave last week on the K1FZ
transformers.
I replaced an ICE box with a KB-1 on my 170 meter long X 2 meter
high Beverage. The terminating resistor came out optimum at 590 ohms
per Bruce's instructions on how to "tune up." I used the feed line isolation
scheme on page 7-19 of ON4UN's book. The KB-1 is MUCH less noisy;
an improvement of at least 3 db S/N!
I then replaced a "ZJ" amplified box with a KB-1 on my EWE antenna.
There is a broadcast station 30 miles off the back of the EWE operating
on 1430 khz, so I have the luxury of being able to tweak the EWE while
enjoying country music. The signal strength when unterminated from the
B.C. station was S-9 + 20db. I used a 2K ohm pot at the termination point,
and I was able to completely null out the station! I came out with 1100 ohms
on the pot, and replaced it with a fixed resistor. I use RG-6U feed line on
the EWE (Radio Shack) and a ferrite line isolator at the feed point.
All ground rods on both antennas are 4 feet long. I am delighted with
the performance and increased "quietness" on both antennas.
This is my first experience with RX antennas, so I can only guess why
the K1FZ boxes are so much better:
1. The transformers are wound on a core that is about 20 times larger
than other brands.
2. The transformer is mounted in a plastic box, so that the ground
connections on the input and output side of the box are isolated
from each other.
You Beverage Guru's out there...feel free to add to this list. I am
trying to learn as I go here.
Bottom line: The K1FZ boxes are top quality units, that are obviously
built with TLC. I highly recommend them; and Bruce is readily available
to support you all the way. Your mileage may vary, but I'll bet you will
see a noticeable difference.
(((73)))
Phil, K5PC
"The Dark Ages were caused by a Y1K problem."
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