28.634 ?
Didn't someone intend to write 28.636 (or so) ?
My experience while mobile on 10 Meters in urban areas
while idly 'searching for anomolies' always indictes around
28.636 MHz but this is not why I am writing (pls forgive
my brief digression).
When a frequency is identified, and it seems to
be a 'carrier', and said carrier is reported, are we to
assume said reported frequency is:
a) the receiver 'window' frequency (the display or dial
reading which produced a 400 or 1000 Hz beat
note in the receiver's speaker). Using this method
will, of course, result in different reported results
for USB or LSB receive modes.
- or -
b) the actual nominal 'carrier' frequency - as determined by
'zero-beating' with said unknown carrier? (I do this by
selecting USB and shifting my IF (IF Shift) so as to allow
a zero beat to be performed against the unID carrier.)
I vote for "b)" as being the reported value in all such reports.
Jim / WB5WPA /
----- Original Message -----
From: "Jim Brown" <jim@audiosystemsgroup.com>
To: "RFI List" <rfi@contesting.com>
Sent: Thursday, January 06, 2005 9:38 AM
Subject: [RFI] Fwd: Re: [TenTec] RE 28.634
> Gentlemen,
>
> The following post from the TenTec reflector is interesting because it
> illustrates the obvious need for a list of common "birdie" frequencies and
the
> equipment that produces them. I've edited this post down a LOT, and it
went on
> for three days while hams around the world triangulated, gyrated,
prognosticated
> about signals from outer space (how could it be everywhere and triangulate
> everywhere?), and talked about calling Riley. All of us have been in the
position
> of wanting to chase these things but not knowing where to start. Of course
we can
> DF them, but there are literally hundreds of them within the ham bands I
use. It
> would be a lot faster if you knew what you were looking for.
>
> Would someone volunteer to collect the data for such a list if we
contribute to
> it? I would volunteer space on my website for it. As a general procedure,
I
> suggest that known frequencies of unknown sources be posted to the list,
so that
> those who have tracked them down can identify them.
>
> To start the ball rolling, here are some frequencies I've found that I'm
sure are
> produced by 10BaseT Ethernet. 3511 kHz, 10106 kHz, 10122 kHz, 14030 kHz,
and
> 21052 kHz.
>
> Jim Brown K9YC
>
> ==================BEGIN FORWARDED MESSAGE==================
>
> What Uses Color Decoders
>
> Every TV monitor and TV receiver (or projector) that displays video from
> composite video or S-video sources has a color decoder.
>
> VCR's and laserdisk players do not have color decoders because, although
they
> may isolate the luminance and chrominance from composite video, they do
not
> decode the chrominance signal.
>
> The NTSC color decoder takes the chrominance (color) signal modulated on a
> subcarrier and demodulates it to obtain two color difference signals such
as Pb
> and Pr. Then it recreates red, green, and blue content signals (RGB) from
the
> color difference signals and the luminance signal using mixtures of the
latter
> three signals or by performing a matrix transformation. Although this
discussion
> is for NTSC, PAL uses a similar color decoder.
>
> A comb filter or (less expensively) a bandpass filter is used to isolate
the
> chrominance content from the total content of composite video. For
S-video, the
> chrominance signal is already separate from the luminance.
>
> To reduce artifacts in the picture, the 3.58 Mhz (actually 3,579,545.4 Hz)
> subcarrier is suppressed as much as possible from the chrominance signal.
>
> In order to decode the color signal, a pure 3.58 Mhz subcarrier signal in
the
> proper phase is needed. It is generated locally by the color decoder. At
the end
> of every scan line, in a part of the waveform called the back porch, there
are
> about eight cycles of the subcarrier used for synchronizing. So long as
the
> local oscillator does not gain or lose more than a quarter of a cycle in
63.5
> microseconds (one scan line time) these "color bursts" will keep the local
> oscillator in sync. and in phase
>
>
> Quoting George <w2yj@highstream.net>:
>
> > I thought there was a reply earlier today or yesterday explaining that
this
> > was probably a color burst crystal frequency? The note indicated that
the
> > power was turned off in the house and the signal disappeared???
> > Can anyone verify that the signal is not internally generated by our
modern
> > electronic "things"?
> > Help me understand.
> > George
>
> > ----- Original Message -----
> > From: "David S.McCallum" <w7sac2@cox.net>
> >
> > > From: "Dave Edwards" <kd2e@comcast.net>
> > >
> > > So how 'bout some beam headings?
> > > Let's see if it can be triangulated (sp?)
> > > at all!!
> > > I'll check myself when I get home.
> > >
> > > ...Dave
> > > ----- Original Message -----
> > > From: "Tommy Bennwik" <bennwiktv@hotmail.com>
> > > To: <tentec@contesting.com>
> > > Sent: Wednesday, January 05, 2005 4:30 AM
> > > Subject: [TenTec] RE 28.634
> > >
> > >
> > >> 28.364 & 14.317 abt S-2 in Stockholm. Hiding under my bed!
> > >> SM0PCA /Tommy
> > >>
> ===================END FORWARDED MESSAGE===================
>
>
>
> _______________________________________________
> RFI mailing list
> RFI@contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
>
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|