Gene wrote:
>It tends to shift around but seems to remain about 20
>to 40 khz wide all throughout HF. The static appears at
>about every 150khz from 2mhz clear through 20mhz.
Hi Gene,
What you're hearing is the RF emissions from the free running oscillator found
in a cheap touch controlled lamp. I'll bet you a new QRO amplifier on it!
They're made in Taiwan and are not UL listed. Some are worse than others
depending on age. As long as they're plugged in they'll generate noise up to
2 or 3 blocks away! I have tracked down 4 nearby lamps in my neighborhood in
last 5 years.
If the signal's really strong, you may be able to trigger the on/off or 3-way
level control. I was able to do this to a new neighbor's lamp. The day they
moved in I was at the rig and actually heard them plug it in. I tuned to the
bottum edge of one of the 40Khz wide pulsations and keyed up on CW briefly.
The pulsation shifted up in frequency!!! So I retuned and keyed again. It
shifted again! I repeated the whole sequence a third time with same result.
On the forth transmission it shifted way down back where it started.
Definitely a 3-way...so I continued to cycle the lamp like this for a few
minutes IDing every now & then. Suddenly I heard them unplug it!! Then they
plugged it back in so I very deliberatley and with rhythm cycled it through
the levels and off again. They'd turn it back on and I'd turn it off again!
Boy was this fun!! They finally unplugged it and left it unplugged.
...until the next day. When I got home there it was again!! So I waited
awhile before playing the "Haunted Lamp" game again. Near bedtime I struck up
another conversation with the lamp. In no time at all it was unplugged again.
I never heard from this lamp again! This may not be the best solution,
however, especially if they figure out your causing the lamp to go on & off.
In another case, I was to far away to trigger the lamp. (I hv no amplifier.)
So after locating the house I contacted the young woman that lives there and
explained what the situation was. I tried the "Your lamp must be
malfunctioning and might be a fire hazard" story, but it didn't seem to phase
her. She said they were too pretty to get rid off! She had two of these RF
monsters, one on each night stand. So I asked if I might take one in to get
it repaired.
I researched who makes the lamps and who sells them here in Omaha. I then
contacted Imports Intl. here in Omaha and bought a new controller for $6.00
and installed it. Only a slight reduction in noise. Interestingly, I found
one AC outlet in my kitchen which didn't propagate any noise at all!! Might
be because of the GFI on that outlet or wiring configuration. I then tried
some of the cures found in the ARRL's RF Interference book (GREAT BOOK!) and
in some old QSTs. You can get this information via the ARRL e-mail server by
sending an email with
SEND RFILAMPS.TXT
QUIT
in the text to arrl-info@arrl.org , or if you'll send me your e-mail address,
I'll send it to you direct. Also, if you call the ARRL they'll send you
reprints of Hints & Kinks and Technical Cooresponance dealing with these
lamps. I wrote up my experiences and sent it in to QST, but they said they
couldn't publish it because they said didn't want to promote my "Haunted Lamp"
method as a solution. But Al Brogdon, K3KMO, sure thought it was real funny
and wrote me a nice letter relating an RFI story of his own from his college
days.
I was able to clean up one of the young woman's lamps to a tolerable level.
While the other lamp was still annoying when on low or high level only! I
asked her to use only the mid-level setting if possible, but she seemed to
like to use the low level for mood lighting always after about 1am or 2am.
She was a young single woman after all ;^)... If she only new how little
privacy she had with these lamps. She has since gotten rid of both lamps to
my delite! Now what can I do about my other neighbors new RF/wireless fence
for his German Shepherd. The poor dog is going to hate contest weekends!
73,
de ed
K0iL
-.-. --.- -.. -..- -.-. --.- -.. . -.- ----- .. .-.. -.-
Eddie Jay Edwards E-mail: eedwards@oppd.com
P.O. Box 375 Amateur Radio Call: K0IL
Elkhorn, NE 68022-0375 AK-SAR-BEN ARC Past-President, 1996
Visit Ak-Sar-Ben ARC home page at URL> http://www.probe.net/~aarc
.-- .... -.-- .-. ..- .-. . .- -.. .. -. --. - .... .. ...?;^)
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Sponsored by: Akorn Access, Inc. & N4VJ / K4AAA
|