Brian wrote:

Just picked up an ANC-4, and am pleased with its performance so far;
however, I'm having trouble with my noise antenna, almost regardless of
length, being overloaded by a local broadcast station. According to the
manual, as well as a post Steve submitted here a few months ago, there's a
jumper which can be moved to attenuate the MW band. Unfortunately, this
jumper, JP3, isn't obvious to me on this board. I'm not sure if it has been
removed by the previous owner, as I bought it used, or if I'm just not
getting something. Is this a pretty straight forward thing that I'm just
missing somehow? Also, as far as wires go, which have you found to perform
the best as a noise antenna? I'm currently using an inverted L of sixty or
so feet phased against the ALA-1530, which works fine aside from the
overload issue.

-Brian


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.