Yes, the average power may be pushed higher, but is the intelligibility of the
signal any better. Lately when I go up on SSB, I hear a lot of signals
compressed beyond the ability to understand. Maybe it's just my old ears
Dave
WA3MKB
-------------- Original message --------------
From: Mike Schatzberg <wow_chf@hotmail.com>
>
> Hello O2 Fans:
>
> To quantify the issue a little better, my measurements show that the O2
> produces
> an average power output that is about 3 db lower than the typical imported
> radio. Even with the compressor set at 7, the O2 will produce about 20 to 25
> watts average output at 70 watts PEP, while a Yaesu Mark V, with the RF
> Clipper
> on and set at 4 to 5 db, will produce at least 40 watts or more when the PEP
> output is 70 watts.
>
> The ALC system in the O2 is entirely different from any off shore
> manufacturer.
> It is so very fast to provide current limiting and protection for the finals,
> not specifically to avoid overdriving an amplifier. This system provides
> excellent final protection, but seems to limit the development of the
> transmit
> envelope.
>
> Of course, there are significant differences between an RF Clipper and a
> Compressor. There alone, the differences are enough to easily see a
> difference
> in average power, especially when driving an amplifier. Ten Tec seems to
> prefer
> the lower distortion of a compressor, as opposed to slightly higher
> distortion
> and more average power output with a Clipper.
>
> I have experimented with changing the time constants in the hardware ALC for
> the
> O2. By the time I got the average power output increased, the signal already
> had begun to distort. If indeed this is the issue, the timing changes will
> have
> to come from the software side. There are probably also reasons for the ALC
> to
> be this fast in regards to the DSP system in use.
>
> The audio in the O2, even with the compressor set at 7 is very good, and very
> strong. It works well in pile ups, and is very distinctive sounding. The
> system works as Ten Tec wanted it to. My amplifier clearly doesn't need to
> work
> as hard when being driven by the O2, and maybe that isn't such a bad thing
> after
> all.
>
> BTW, I see the new K3 will indeed use a RF Clipper.
>
> 73 and Happy DXing,
>
> Mike
> W2AJI
>
> > From: ronc@sonic.net> To: tentec@contesting.com> Date: Tue, 5 Feb 2008
> 13:48:12 -0800> Subject: Re: [TenTec] ORION II the right rig for SSB ?> > I
> agree with Merle that the sound of the processing is among the best out >
> there,
> but most operators notice that Orion's don't seem to drive a linear > as hard
> as
> most other rigs. I looked at the waveform for quite some time on > a spectrum
> analyzer and I believe that the problem is due to instantaneous > and
> absolute
> ALC action (and possible over reaction) on even the most > fleeting peaks.
> This
> results in a lower observed average output although > the peak output appears
> to
> be correct. The lower average output probably > has little effect on the
> overall
> intelligibility of the signal or its > ability to bust through a pile-up, but
> this is an area that could use some > more study.> > Ron N6IE> www.N6IE.com>
> > >
> ----- Original Message ----- > From: "Merle Bone" > To:
> > Sent: Tuesday, F
> ebruary 05, 2008 10:20 AM> Subject: Re: [TenTec] ORION II the right rig for
> SSB
> ?> > > > Ben (ON5GQ) said:> > "In the archives of this reflector and reviews
> on
> Eham I found also > > negative> > comments regarding the average SSB power
> output of the Orion II."> >
> --------------------------------------------------------------------------------
>
> --------------------------> >> > Ben, like many other recent DSP based rigs,
> the
> Orion/Orion II V2 code has > > been> > "work in progress" for some time.
> There
> was a point in the firmware > > releases where,> > in my opinion, the V2
> speech
> processing was not great. However, that has > > been fixed> > and I now
> believe
> that the current V2 speech processing is among the best > > I have> > ever
> seen.> > See post > >
> http://lists.contesting.com/archives//html/TenTec/2007-05/msg00478.html> >> >
> The Orion/Orion II V2 speech processing algorithm delivers 15-20dB of > >
> compression with> > solid high quality speech. I think it represents a real a
> dvantage for SSB > > contesters> > or DX'ers.> > 73, Merle - W0EWM> >
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> >
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