"Very basic math of course, but unless
everyone has identical center frequencies, quite necessary."
Not at all! It doesnt matter if you set your rig at whatever freq (take
3581.5 your example) and the audio you have is at 1.500 on the waterfall.
The signal we are talking about is the one on 3583. If you spot 3.583, and
the rest of us see it, and click on it our rigs will qsy to whatever
frequency will give us that same exact spot on our waterfall. I. E, since
my offset is 1000, the correct waterfall position (sweet spot of my sound
card) will show as 3583 exactly 1000 cy from the edge of the waterfall- and
my rig has QSYd to its correct positon for that to happen (3.582).
Your Rig VFO readout 3.5815 - plus waterfall 1.500 equals 3.583
My Rig VFO readout is 3.582 - plus waterfall 1.000 still equals 3583
Each and every rig out there does the same thing, but with different
numbers, if the offsets are not the same as ours.
The rig freq, plus the offset freq is still going to equal 3.583 - which
should be the spotted freq.
This is why every one should use, not the rigs BFO, but the actual Rig +
Offset when we are spotting stations.
No manual addition/subtraction is necessary. If we have done our tuning
correctly, and the signal is set exactly on that "sweet spot" (the offset
position) in the waterfall window, the signal should be smack-on and the
software immediately copying the station. It is always disconserting to see
someone who has spotted another station on : say 14069, or 14070, or 14.071,
because 9 chances in 10, that person has simply set his rig on that freq,
and is ignoring the waterfall audio frequency readout. (Unless of course the
spotted station IS actually 1 KC above that freq) Some software doesnt even
have a freq readout on the waterfall, but just 0 to 1000 or 2 or 3000, but
that should not matter, since the RF plus AF(offset) is known. Some
software may not spot using the additive freqs, but I have yet to use one
that didnt.
I was quite confused about all this at first and also spotted people
incorrectly with just the rigs VFO freq. until I figured out what my
software was doing, and where people were actually reading the signals on
the waterfalls.
Danny Douglas N7DC
ex WN5QMX ET2US WA5UKR ET3USA
SV0WPP VS6DD N7DC/YV5 G5CTB all
DX 2-6 years each
.
QSL LOTW-buro- direct
As courtesty I upload to eQSL but if you
use that - also pls upload to LOTW
or hard card.
moderator [EMAIL PROTECTED]
----- Original Message -----
From: "KV9U" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Tuesday, December 19, 2006 9:35 PM
Subject: Re: [digitalradio] Establishing digital calling/beacon frequencies
?
> Establishing separate spot frequencies for each mode seems a bit
> impractical. The 003 frequency is close to where I operate on any mode
> except PSK31. On the later, I usually set my dial frequency on the
> watering hole frequency and use the cursor to pick out individual
> signals or to set my transmit frequency.
>
> Since some of us can not wisely use a 1000 Hz center frequency for the
> best filtering, it seems to me that we should specify the actual
> frequency of the signal. If I want to be on 3583 for MFSK16, I put my
> dial frequency in such a position that my transmitted data is centered,
> or close to centered on that frequency. Since my equipment is designed
> to center on 1500 Hz, I typically set my dial for 3581.5 and then my
> signal is on 3583 when I move the cursor to 1500 Hz on the waterfall.
> Other stations may have different requirements, but not all would
> necessarily be on 1000 Hz above the dial frequency. Indicating Dial
> frequency +1000 though would be perfectly acceptable. Then I would
> realize that if you were 3583 dial +1000, your actual signal would be on
> or near 3584 and I would place my dial at 3582.5 in order to center you
> on 1500 Hz on the waterfall. Very basic math of course, but unless
> everyone has identical center frequencies, quite necessary.
>
>
>
> Andrew O'Brien wrote:
>
> >Should we consider trying to establish calling or beacon frequencies
> >for the non-PSK31, non-RTTY, non-ALE, digital modes? I'm thinking
> >along these lines because I'm having to dial between 14072 and 14110
> >on 20M for those few opportinties to catch MT63, Olivia, MFSK16,
> >Hell, PSK63, PAX2, DominoEx, Throb, Chip64, etc, etc. 40M is a
> >similar "chore". If I park on ,say, 14075 ...with a wide filter I
> >can hear some of the folks that start up but often miss the guys that
> >are riding high on 14108.5
> >
> >I wondering if we could informally establish a calling frequency for
> >MT63, Olivia, MFSK16, Hell, PSK63, PAX2, DominoEx, Throb, where we
> >all agree to less than 20 second CQ calls and 60 seconds taken to
> >coordinate a move to a free frequency. Ideally I would love to have
> >an APRS-type beacon system where we can see who is on frequency via
> >our maps, and then move people off the freq to arrange QSO's , all
> >control operated not unattended beacons. My recent 300 baud packet
> >tests and PAX2 tests suggest that these two modes are not robust
> >enough fo weak signal detecting. Olivia would be idea but is slow
> >for beacon-type work. I guess we could establish it so that any
> >digital (data) mode could be used to "beacon" with, but perhaps
> >encourage nothing more than 500 Hz wide signal . I would probably
> >beacon with 16/500 Olivia.
> >
> >Any thoughts on this? What would be a good 20 , 40, and 80M
> >frequency? We would need one that all IARU regions could use, one
> >that most ham license classess can access, one that is not common for
> >others to CQ on. One that does not have a lot of automated PACTOR
> >traffic, and ideally one that is outside the usual RTTY contest
> >range . Suggestions ?
> >
> >How about 14073, 7073, and 3573? These would be the radio dial
> >frequency , all USB, AF frequency standard would be 1000 Hz.
> >
> >Would they work for most parts of the world? "73" would be easy to
> >remember!
> >Of course, we would refrain from beaconing if the frequency is in use.
> >
> >
> >Andy K3UK.
> >
> >
> >
> >
> >
>
>
>
> Connect to telnet://cluster.dynalias.org a single node spotting/alert
system dedicated to digital and CW QSOs.
>
>
> Yahoo! Groups Links
>
>
>
>
>
> --
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>
>
