G'day,
I saw KFIs carrier last night at Hobart, Tasmania, Australia. A screen
shot is at www.qsl.net/vk7ro/640khz.jpg
When using an HF dipole antenna the signal was overwhelmed by several
"local" stations on 639KHz, but I could see the KFI carrier when using my
LF active 6' vertical with its 300?KHz lowpass filter.
Sorry about the receiver drift, but my Yaesu FT747 is not happy about me
using a fan heater in the shack to keep warm.
At 10:53 AM 8/8/03 -0400, you wrote:
Here's an unusual DX reception opportunity which may not be possible from
the U.K. and EU, but might be fun to try.
KFI, a 50 kw AM station in Los Angeles, California, has an unusual
transmitter problem which is causing a +/- 0.5 Hz deviation of their carrier
over an 11.5 minute period. This results in a very distinctive "square wave"
on an Argo screen. Dale Rice in Oregon first noticed it, and I have
confirmed it (at a distance of 4000 km) in Massachusetts. Given the time
differential, there might be a narrow window before U.K. sunrise that would
permit reception. If anyone is interested in trying, Carl Swanson at KFI
Engineering has offered to send special QSLs to those providing proof of
reception. Here is what he told me, and the rest of the details:
-----------------------------
"Please forward this email onto your Lowfer mailing list and let them know
that I will send any interested listener a verification letter and a KFI
sticker if they will e-mail me a standard reception report and a URL to a
screenshot of the carrier like you did (with reception details added to the
JPG photo itself). Let's try to keep it under a hundred reception reports
please, quantity of reports isn't as important as widely varying locations
of reception.
To recap, each email should have a name/address/city/state/zip/phone
number, a standard repection report (date/time(z)/location), and a URL to a
screenshot of whatever software they are using showing this unusual
waveform, with the same reception details listed in the JPG itself. No
attachments to the e-mail, my corporate e-mail will strip any attachment and
I will never see it."
-------------------------------
I have Carl's email address, and will provide it to you on request. I don't
want to post it here, lest it turn into spam fodder when the reflector is
archived at QSL.net. Here are the details for your search:
KFI is in the Los Angeles area, and runs 50 kw on 640 kHz. Dale Rice and I
have observed their transmitter frequency to be centered on 640.0084 kHz,
varying about +/- 0.5 Hz in a square-wave pattern. Each "cycle" of the
square wave takes about 11.5 seconds. It can be nicely seen on Argo screens
from 20 through 60 seconds (Dale has used 120 as well). An Argo 20 second
screen shot from my house (2500 miles!) can be seen at:
http://webpages.charter.net/w1tag/files/KFI080603.jpg
I would suggest Argo 30 or 60 second screens as the best. Here on the east
coast, the signal has been visible between 0400 and 0900 UTC. Such an odd
waveform will be very distinctive, and excellent proof that you have seen
KFI's carrier.
So, have fun... and pester me for that email address.
John Andrews, W1TAG
73, Ric, VK7RO
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