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John Barnard · December 23rd 06, 02:29 AM posted to rec.radio.shortwave

Brian wrote:
I don't have that problem, however I'd be inclined to try a LC series trap
in series with the offending antenna, as the cheapest experiment (pick L
and C
to resonate at the broadcaster's frequency, to remove it perferentially),
or even
just a resistor, to see if overload is really the problem. Or a MFJ-956
passive
antenna tuner, off the shelf.

Or swap the antennas, and null the broadcaster with the ALA-1530, which is
then the
noise antenna, by orienting it. Or you can null the station with the wire
antenna,
though it's likely to be more inconvenient to reorient. Every antenna has
null.

A slight disadvantage of tuned traps is that they change the attenuation
across
the bandwidth of a station, so you can never quite eliminate the entire
station
across the audio spectrum because the second antenna still has the
original
shape.

--
Ron Hardin

On the internet, nobody knows you're a jerk.

I compared the board to a schematic I found online which shows the bc trap
and jumper components. Apparently the model I have is an earlier version
lacking these revisions. Regarding your suggestions, swapping antennas
proved ineffective, as the loop generally did not hear the noise, and when
it did the level was far lower than on the wire, making canceling difficult.
Using a twelve foot dipole I had no overload issues, but found it to be too
short in some instances. I'm still looking for instructions on building a
trap or bcb filter, but I'll keep experimenting with antennas in the
meantime.

-Brian

Brian,

I have plans on how to build a BCB filter that I could send to you as a
PDF once I return to work and scan the document. Fortunately, I don't
get back to work until Jan. 2.

Cheers!

John Barnard