> Well, mostly I was thinking about what gets foisted off on us by
> Microsoft every time there is an "upgrade".
Yes! But this is part of the landscape of today's operating systems. You can
pick your OS to critique and there will be people on both sides to cheer with
you or yell at you. Windows vs Mac vs Linux vs embedded ??? It seems that
developers pick their OS and cope with the pros and cons. The major effort of
PowerSDR has been to use the open source philosophy of 'free' and
'collaboration' for the key DSP components and publishing the SOURCE of Windows
code for 'collaboration'. In addition the stated development direction is
towards a newer architecture.
> Which is why we need a set of snap-together modems neatly integrated
> into the radio. Signal stream in, data stream out. No worrying about
> what it looks like because that is what the UI module is for and that
> isn't part of the modem. Now you just reuse the modem LEGOs. Want a
> better modem, drop it in. You don't need a whole new system or whole
> new application.
If you search the reflector archives you may be pleased to see that is EXACTLY
where the newer architecture is headed.
> Unless, like me, the bloody legacy applications DON'T WORK RIGHT!
> (Sorry, that's the frustration speaking -- oh yes, that IS a new PCI-E
> display adaptor next to the extra gig of RAM and the separate IEEE
> 1394 card. Thanks for asking.)
Agreed, this is the least 'plug and play' radio I've ever encountered. Most of
my early frustration (uh, excitement?) came from trying to get first one
computer working, a Dell 2.4ghz. Now I've got a 3.0ghz hyperthreaded machine
doing the PC work. The hypertheaded machine is much better, but still not
there yet. I'm slowly building up a quad core machine to dedicate to the
radio.
>
> I hope to get to that point someday!
Get hold of some snap on ferrite cores from your junk box or check here on the
reflector for the best places (cheapest) to buy them. As you start radiating
power you may need these.
>
>
> And there is nothing quite like those little spur spikes skipping
> hither and yon as one meanders through the spectrum. (That is
> something I am worried about because I think that is a function of the
> DDS LO.)
The spurs end up being scarier visually than audibly. When I first tuned
across 6m there were picket fences of moving spurs that scared the heck out of
me. They disappeared in the next software version.
Then there is the phenomenon of an actual RF signal on the panadapter, with the
'Avg' button pushed in, bouncing up and down as you tune across the band. This
appears to be a spur that changes amplitude as you tune but is really caused by
the averaging function taking a moment to work. The bouncing up and down of
the signal goes away as you tune if you turn off the 'Avg' function.
Disconcerting but understandable.
Years ago I did some digital DSP work using an oscilloscope for the spectrum
display, this is before we had PC's to use. As I tuned my digital oscillator I
followed the 'blip' on the screen of the scope move. Every few cm's of
movement the scope screen would break out in an array of picket fence spurs.
Finally the lab guys and I figured out that we were observing very common
mixing artifacts. They occur all the time in mixers. In old style radios
they are very carefully dealt with over many iterations of trial and error.
There is some math but there is a lot of trial and error. With these new SDR
radios, the Flexradio being the latest and greatest, we get to observe these
artifacts if and when they occur. The programmers have been fantastic in
working them out of the system. I attribute that to their skill, dedication
and the visual tools that the panadapter display provides.
> Well, the radio is too but we have such a long way to go for the
> software to catch up that I think it will work for a bit longer yet.
> (I certainly hope so as I share your vision. I passed up the K3 for
> the '5K.)
yes, as did I. It's taking a leap of faith. No doubt in that!
> Well, faster than what? My whole (subtle) point was that once your
> computer is fast enough, making it faster won't make things perform
> better ... until you add something else in that requires more CPU
> cycles. So if the display is updating fine, you are sampling at
> 192Ksps and there are no dropouts, and the other applications, e.g.
> MixW, are running without gaps in the waterfall and garble in the
> text, then paying for extra computer power doesn't make it run better.
I've yet to get to 192 Ksps AND use all the filter buttons AND do auxiliary and
legacy software. sigh.
> Well, not quite. It is more like FM -- once you have enough signal for
> full-quieting, more power won't make the signal any better.
agreed, but I keep adding functions and I want more features. Every addition
needs more compute power and less hassles from interrupts and system processes.
> But if you want to stick with the automotive analogy, there is always
> the 65mph speed limit. :-)
I always disliked the speed limit. ;-)
>
> Some computer applications will consume (and perform better) the more
> CPU cycles you can throw at them. This is what the gamers are after
> since more power means more detailed rendering and faster display
> updates (frame rate).
That is exactly what this radio and computer is like. The more compute power
the more bandwidth I can display. I can use more filters and more applications
running simultaneously. Exactly. You've nailed the situation with this
'gaming' idea. They want frame rate, we want more features.
The Flex 5000 + PowerSDR needs a certain amount
> to do its job and it won't run faster, better, quieter, higher BDR,
> higher IP3, etc., with a faster computer.
But this is a moving target! True, the IP3 is fixed by the input circuitry,
but hamming is more than a single parameter. How quick can you see a new
station and click on it? How much noise can you get rid of? How many
different modulation schemes can you simultaneously decode? These are computer
power dependent. As long as I've observed the computer field I've seen any and
all new computer capabilities swallowed up by the programmers. Not all new
code is bloat, there is a lot of cool and interesting coding concepts that are
being invented and implemented, a lot of it enabled by the availability of
cheap computer power.
>
> Now maybe that isn't valid when you decide to run CW Skimmer and try
> to suck in 200 simulataneous QSOs but even then, you just need enough.
Yes, but I'm not there yet. I'm still putting together my own 'super computer'
(discretionary spending only heheheh)
> And I am trying not to go over the top with being negative.
Thank you!
>
> (But what about those spurs?)
Where do you see them? (All of my observable spurs disappeared many versions
of software ago.)
Ted, NX6C
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