Posted by
Richard Smith-23 on
Oct 09, 2007; 3:29am
URL: http://elecraft.85.s1.nabble.com/Comparison-K3-and-SDR-5000A-tp454268p454271.html
> W4VZ wrote:
> Thanks for your analysis which is probably representative of
> computer-savvy hams. Not everyone has a dual-core processor with 2GB
> of RAM (required for the 5000) running his station and I also question
> how many would be willing to upgrade motherboards, processors, etc
> themselves. Maybe the truth lies somewhere in between our two
> estimates. In my case I only have a 250 MHz Win98SE system in my
> shack, so I would need a completely new system. As I implied
> previously, IMHO the 5000A appeals to folks who love to tinker with
> computers and software. For those who don't, the 5000C Plug and Play
> package may be probably more realistic.
I may have given you the wrong impression. Although I am capable of
changing a motherboard, I in no way meant to imply that such knowledge is
required or that changing a motherboard is necessary. My point is that
computers and memory are pretty cheap and readily available today. For the
$600 you mentioned, you typically get a pretty powerful computer right off
the shelf - with plenty of power to run the SDR-5000A (you don't need
dual-core - but they are pretty standard these days at this price). No need
to change the motherboard or anything else. I was trying to make the point
that, if you are a "computer-savvy" ham you can even save more money by
doing it yourself. But a $600 PC right out of the box will work just fine.
Also, by all reports the SDR-5000A is plug and play with the PC - but I
guess you do need to be able to find the firewire port and load some
software.
>
>> Ergonomically, I must say that I really like the computer GUI of the
>> PowerSDR.
>
> Again this gets down to personal preferences. HF DX contests
> are one of my personal interests. I cannot imagine operating a
> mouse/GUI as quickly as using the classical knob UI refined over some
> 50 years of contesting. N6TR is probably one of the finest contest
> operators in the world, who I believe has won the NCJ CW Sprint (the
> most difficult contest in the world) more times than anyone else.
> Tree is also very savvy about computers and software (he's the author
> of TR-Log...a high performance contest program for SO2R), having even
> written a robot program to control all TX, RX and logging functions
> many years ago (i.e. no human involvement required!) When I see top
> contest operators like Tree switch to SDRs with GUIs, then I'll become
> a true believer. Tree is a beta tester for the K3 and is switching
> from two TS850s to two K3s. I know some VHF contesters are using SDRs
> successfully, where the bandscope helps find stations on otherwise
> dead bands, but the pace of VHF operation (i.e. QSOs/hour) is much
> lower than in HF contests, where top operators make octaves more
> contacts in the same period of time.
I will admit that 50 years of contesting by turning a knob is a lot of
momentum to overcome. You certainly can't argue with success, and I
wouldn't expect a top contesters to readily change their form and adopt a
new paradigm without some certainty of success. Of course, they might just
get picked off in the next contest by someone who has. I think there is
great efficiency in the PowerSDR GUI interface. I'm a casual contester at
best so can only tell you my experience. Being able to see the whole
spectrum at a glance and pick off signals instantly with a point and click
of the mouse seems to me to be ideal for contesting. The resolution of the
PowerSDR bandscope is quite good and the ability to select stations on a
crowed band is quite remarkable - especially for CW. Want to monitor
another signal, stick the second receiver on top of it with a single click
of the mouse. Send the audio from different receivers to separate speakers.
You are already at the keyboard with logging and other control programs -
why keep reaching up to tune the radio? I think it is just a matter of
time before some serious contesters adopt this new approach.
>>
>> But in a perfect world, I'd own both.
>
> The way I see it, the K3 allows you to have both. You have
> the superior RX performance benefits (IMD, BDR & Phase Noise over a
> wide spectrum) of a narrow front-end superhet rig *plus* an SDR
> bandscope on the buffered IF output. The K3 will allow the latter
> for a small increment (e.g. a $15 Softrock40, free Rocky software or
> even PowerSDR, some additional isolation buffering, a $100 soundcard
> and a 1 GHz 256MB (WinME or higher) computer (non dual-core). I'm
> guessing <$400 is a reasonable increment.
Bill, I believe you are mistaken here. Adding a bandscope to the K3 does
not give you the benefit of the SDR rig. Yes, with your approach you will
be able to see signals in a bandscope format. But for the SDR-5000A run by
the PowerSDR program, the bandscope is a fundamental part of the GUI for
controlling the radio. You don't only see the signals on the bandscope, but
you tune to them by simply pointing and clicking on the bandscope. You can
also drag the signal you want into your bandpass. You can adjust filter
widths to exactly tailor the bandpass to the signal you see on the bandscope
by dragging the edges of the filter. You point to place your second
receiver on any signal you want. You control the radio through the
bandscope. Your bandscope solution without the GUI interface functionality
is just a pretty picture. And you don't get that functionality by twisting
knobs on the K3. There is a lot of software that needs to be written to
control the K3 to emulate these bandscope GUI functions. You also need to
be very computer-savvy to implement the solution you suggest, and the
performance of the bandscope will not likely approach that of the
SDR-5000A..
>
> There is no question the bandscope is the neatest feature of
> an SDR, but to get it you must give up fundamental receiver
> performance. You are also saddled with a user interface that may be
> glitzy, but cannot (IMHO) compare for truly fast-paced operating with
> classical knobs. When I see *any* Top Ten class HF contest ops (e.g.
> WRTC class) moving to SDRs, then I'll become a believer. So far there
> are none that I'm aware of. Do you know of any? The beauty of the K3
> is that you can add the bandscope-only features of an SDR for a small
> increment, yet don't need to sacrifice RX or ergonomic performance to
> get it.
>
I think the question of giving up anything in fundamental receiver
performance is far from answered. I also think the inherent efficiency of
GUIs like PowerSDR will prevail eventually. I just don't see how turning a
knob could possibly be faster than seeing, pointing and clicking. And more
features are being added all the time. You seem to make the assumption that
knobs beats computer control ergonomically every time. Personally, I think
the PowerSDR software is generations beyond the old-school radio control
programs that control a hardware rig with serial commands that emulate
twisting knobs. Based on my experience with such programs, I would have to
agree with you that knobs have it all over computer control when it comes to
ergonomics. However, since using the PowerSDR software my opinion has
changed. I no longer need knobs to feel comfortable using a radio. I guess
you just have to use it for a while to see what I mean. It is very
intuitive, instantaneous and comfortable. Of course, you can add a knob or
use the mousewheel to dial up frequencies and tune in stations the old
fashioned way, but why?
Thanks for the spirited debate.
73,
Rich W1EZ
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