I also noticed that Orion filter skirts after 1000 hertz and up get very
sharp. They are much sharper than the Icom filter skirts in the normal SSB
range. I don't know why the Orion filters are not sharper in narrow CW
bandwidths. The rx340 filter skirts are extremely sharp even at 100 hertz.
The rx340 100 hertz filter is still only 120 hertz wide at 60 db down.
Carl Moreschi N4PY
Franklinton, NC
----- Original Message -----
From: "Steve N4LQ" <n4lq@iglou.com>
To: <tentec@contesting.com>
Sent: Monday, September 27, 2004 9:03 PM
Subject: Re: [TenTec] Orions SO2R in CQ WW RTTY
> "FOR TOP NOTCH CONTEST GRADE RTTY USE, ORION'S DSP NEEDS TIGHTER SKIRTS"
>
> I noticed how broadly the Orion tuned while doing A/B test between it and
> the Pro2. The PRO2's filters are almost vertical and signals drop like a
> rock at the edge of the passband. You can taper them off by staggering the
> PBT for non-contest operation. At 100hz BW, the Orion seemed really broad
in
> comparison.
>
> Steve N4LQ
> ----- Original Message -----
> From: "Bob Henderson" <bob@cytanet.com.cy>
> To: <tentec@contesting.com>
> Sent: Monday, September 27, 2004 4:16 PM
> Subject: [TenTec] Orions SO2R in CQ WW RTTY
>
>
> >I used my Orions SO2R in the WW RTTY this weekend, so I decided to share
> >how
> > they performed.
> >
> > Firstly, both radios were on for the full 48 hours of the event and for
a
> > couple of hours before. I operated the full contest without having to
do
> > any kind of reset at all on either radio. For me this was unsurprising,
> > as
> > the only time I do a master reset is when I download new firmware.
Then,
> > I
> > do it as a matter of course.
> >
> > Overall, I would say they performed superbly. One particular thing I
> > noticed with Orions, which replaced my two FT1kMPs, is that they are
> > better
> > suited to SO2R in the kind of setup I use. What does that mean? Well, I
> > have a rather limited station here. No multiple towers or anything like
> > that. In fact, just one modest crankup with a Force 12 C31XR and a
> > Cushcraft XM240. If you're interested you can see my set up at
> > www.5b4agn.net. This is a new website and my first attempt at it, so
> > please
> > excuse it being a little bit raw & obviously unfinished!
> >
> > The C31XR driven elements for 20/15/10 metres, which are only a matter
of
> > inches apart, are fed with three seperate feeders. I operate high power
> > SO2R using these interlaced yagis. With driven elements so close
together
> > you can imagine the rf field presented to the second radio rx is really
> > nasty. Of course, I use band pass filters and stubs to minimise the
> > problems this causes. BUT with my two Ft1kMPs I could always feel a
> > presence on my second radio when transmitting on the first. What do I
> > mean
> > by a presence? Well, modulation of the noise floor I guess. I also
found
> > that listening on say 20m, within about 10kHz of my 40m second harmonic
> > was
> > a bit messy. What I found with Orions this weekend was that I had no
> > sense
> > of a presence on the second radio when transmitting on the first. Not
> > only
> > that but I found myself to have been working about 1 kHz away from the
> > second harmonic of my 40m signal on 20m without even realising it. In
my
> > view, this experience speaks volumes for Orion's bomb proof front end
and
> > very low phase noise.
> >
> > I have only two critiscisms to level at Orion after this weekend of RTTY
> > use
> > and one of those I suspect may be down to operator error though I'm
> > unsure.
> >
> > 1. My contesting software is Writelog. I ran both Orions set at 250 Hz
> > b/w
> > most of the weekend. Whilst tuning around the bands looking for mults
etc
> > I
> > band map wanted stations which don't answer me after a couple of calls.
I
> > then periodically return to their band mappped frequency to see if their
> > pile up has subsided. The problem I found is this: Every time I
clicked
> > back to a mapped frequency the rx b/w changed. If I had only one Orion
> > then
> > I would probably be thinking this was a logging software problem but I
> > don't, I have two and although the bandwidth changes on both it's not to
> > the
> > same setting. On one radio it always goes to a barn door 1 kHz but on
the
> > other it always goes to 300 Hz which isn't so bad. Though, I'd much
> > rather
> > it stayed at 250 Hz where I'd set it.
> >
> > What determines the b/w set when frequency is changed via the RS232
port?
> > Why is it 1kHz on one Orion and 300 Hz on the other? Anyone know the
> > answer
> > to this mystery? Should I just RTFM?
> >
> > 2. Filter shape factor is really the only significant concern I had
over
> > the weekend. With b/w down at around 250 Hz the DSP shape factor is not
> > far
> > short of 3:1 which really isn't good enough. As a consequence, folks
> > could
> > sidle up real close to Orion's beautifully clean signal and sit there
> > inside
> > my passband causing me grief. I spent way too much time over the
weekend
> > inching up or down in frequency to avoid QRM from folks alongside. This
> > leads me to the following conclusion:
> >
> > FOR TOP NOTCH CONTEST GRADE RTTY USE, ORION'S DSP NEEDS TIGHTER SKIRTS.
> >
> > Incidentally, FWIW the weekend was a lot of fun. I put in 36 hours and
> > finished with he following tally:
> >
> > QSO: 2582; Points: 7550; State/Prov: 100; Countries: 271; Zones: 94 for
a
> > total score of 3,510,750
> >
> > I was placed 4th last year in SOAB (HP). This year my Q's are up by
> > almost
> > 11% but mults are way down and as a consequence so is my claimed score
> > which
> > is about 5% short. Things get tough when 10 metres dies! Hopefully,
> > just
> > as tough for everyone. We'll see when the results come out.
> >
> > 73, Bob
> >
> > Bob Henderson, 5B4AGN, P3F
> > Giolou, Pafos, Cyprus
> > Email: bob@cytanet.com.cy
> > http://www.5b4agn.net
> >
> >
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
> >
>
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