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Comparison: K3 and SDR 5000A

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Bill W4ZV

Comparison: K3 and SDR 5000A

AB8O:
>I would like to hear from my fellow Elecraft fans regarding general
impressions of the K3 versus the SDR 5000A, software defined radio.

Good question John...unlikely it can be answered
completely until after the K3 ships. I've also been following
the 5000, and here are some strictly *academic* thoughts based
on published info:

RX Performance (2 kHz spacing, 500 Hz filter):

Metric K3 5000 Advantage Sources

IMDDR3 94 96 neutral Eric/Sherwood
BDR 138 123 K3
Eric/Sherwood

Note: Sherwood published data for 5 kHz only but the 5000
should have identical IMD/BDR performance at 2 kHz.

Phase Noise:

Rig 1kHz 2 10 20 50 100 1M
K3 -110 -119 -136 -140 -143 -144 -150
5000 -123(flat)*
*(Sherwood) "Phase noise does not fall off at 6 dB per octave as expected.
Flex believes the present phase noise limitations are caused by A/D
clock jitter". ("Clock jitter" is another word for phase noise).

Advantage K3. It has lower integrated phase noise
over the entire spectrum. The 5000's relatively higher
phase noise will likely be an issue, especially for
VHF users.

Form Factor:

This is a religious issue with some. Knobs versus
no knobs. "Real Radios Don't Need Knobs" (Flex's slogan).
I suppose the K3's corollary slogan is "Real Radios Don't
Need Computers". :-)

Cost (for the 5000 it depends on whether you already have
a fairly high-performance computer dedicated to your shack.
I'm going to compare the 5000C which includes the computer
and will assume $200 for an LCD display):

5000C $5098 (no ATU, $200 display plus a $99 knob option)
K3 $2825 (assembled K3/100, KXV3, KRX3, 2X 500 Hz filters)

Of course the K3 does not include a bandscope, but the KXV3
provides the wide bandwidth buffered IF output to do this.
Eventually Elecraft, Clifton Labs or someone will provide
this. The solution could be as simple as a SoftRock40 on
the 8.215 MHz output to something much more exotic. Let's
assume $400 for something like a Clifton Labs Z91 plus
another $600 for an adequate computer and display, resulting
in an additional $1000 for interface hardware, computer and
display. I'm assuming free software based either on Rocky
or PowerSDR. This results in:

5000C $5098
K3+ $3825

Advantage: K3 which will have basic RX performance
exceeding the 5000 (see above) and a parallel SDR bandscope.
Assuming someone like HB9DRV integrates this with his Ham
Radio Deluxe program, I believe the K3 will maintain a
significant price advantage over the 5000C.

Portability:

Metric: K3 5000C

Dimensions: 4X10X10" 8.72X17.67X14.67"
Cubic inches: 400 2260
Weight: 8 lbs. 13 lbs.
Power: Similar...I'm tired of typing!

Advantage: K3. I suspect it will very quickly become a
gold standard for DXpeditions, not to mention contesting.

Let's remember that neither of these rigs is
a finished product and both will likely be upgraded via
firmware/software as they evolve. Both have very good
designers and very good mechanisms in place for customer
feedback, so any weakness today may be solved tomorrow.

I also think there's simply a different mindset
appeal of both rigs. Some of us enjoy tinkering with
computers, software, etc and those will love the 5000C.
Some of us are more into ergonomics, operating, etc
and those may like the K3 better (IMHO). Time will tell.

73, Bill W4ZV

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dave.wilburn

Re: Comparison: K3 and SDR 5000A

Has anyone made an SDR yet that runs on anything but windows?

David Wilburn
[hidden email]
K4DGW
K2 #5982
FP#-1751

Bill Tippett wrote:

> AB8O:
> >I would like to hear from my fellow Elecraft fans regarding general
> impressions of the K3 versus the SDR 5000A, software defined radio.
>
> Good question John...unlikely it can be answered
> completely until after the K3 ships. I've also been following
> the 5000, and here are some strictly *academic* thoughts based
> on published info:
>
>
> RX Performance (2 kHz spacing, 500 Hz filter):
>
> Metric K3 5000 Advantage Sources
>
> IMDDR3 94 96 neutral Eric/Sherwood
> BDR 138 123 K3 Eric/Sherwood
>
> Note: Sherwood published data for 5 kHz only but the 5000
> should have identical IMD/BDR performance at 2 kHz.
>
> Phase Noise:
>
> Rig 1kHz 2 10 20 50 100 1M
> K3 -110 -119 -136 -140 -143 -144 -150
> 5000 -123(flat)*
> *(Sherwood) "Phase noise does not fall off at 6 dB per octave as expected.
> Flex believes the present phase noise limitations are caused by A/D
> clock jitter". ("Clock jitter" is another word for phase noise).
>
> Advantage K3. It has lower integrated phase noise
> over the entire spectrum. The 5000's relatively higher
> phase noise will likely be an issue, especially for
> VHF users.
>
>
> Form Factor:
>
> This is a religious issue with some. Knobs versus
> no knobs. "Real Radios Don't Need Knobs" (Flex's slogan).
> I suppose the K3's corollary slogan is "Real Radios Don't
> Need Computers". :-)
>
>
> Cost (for the 5000 it depends on whether you already have
> a fairly high-performance computer dedicated to your shack.
> I'm going to compare the 5000C which includes the computer
> and will assume $200 for an LCD display):
>
> 5000C $5098 (no ATU, $200 display plus a $99 knob option)
> K3 $2825 (assembled K3/100, KXV3, KRX3, 2X 500 Hz filters)
>
> Of course the K3 does not include a bandscope, but the KXV3
> provides the wide bandwidth buffered IF output to do this.
> Eventually Elecraft, Clifton Labs or someone will provide
> this. The solution could be as simple as a SoftRock40 on
> the 8.215 MHz output to something much more exotic. Let's
> assume $400 for something like a Clifton Labs Z91 plus
> another $600 for an adequate computer and display, resulting
> in an additional $1000 for interface hardware, computer and
> display. I'm assuming free software based either on Rocky
> or PowerSDR. This results in:
>
> 5000C $5098
> K3+ $3825
>
> Advantage: K3 which will have basic RX performance
> exceeding the 5000 (see above) and a parallel SDR bandscope.
> Assuming someone like HB9DRV integrates this with his Ham
> Radio Deluxe program, I believe the K3 will maintain a
> significant price advantage over the 5000C.
>
>
> Portability:
>
> Metric: K3 5000C
>
> Dimensions: 4X10X10" 8.72X17.67X14.67"
> Cubic inches: 400 2260
> Weight: 8 lbs. 13 lbs.
> Power: Similar...I'm tired of typing!
>
> Advantage: K3. I suspect it will very quickly become a
> gold standard for DXpeditions, not to mention contesting.
>
> Let's remember that neither of these rigs is
> a finished product and both will likely be upgraded via
> firmware/software as they evolve. Both have very good
> designers and very good mechanisms in place for customer
> feedback, so any weakness today may be solved tomorrow.
>
> I also think there's simply a different mindset
> appeal of both rigs. Some of us enjoy tinkering with
> computers, software, etc and those will love the 5000C.
> Some of us are more into ergonomics, operating, etc
> and those may like the K3 better (IMHO). Time will tell.
>
> 73, Bill W4ZV
>
>
>
>
> _______________________________________________
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>

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dj7mgq

Re: Comparison: K3 and SDR 5000A

> Has anyone made an SDR yet that runs on anything but windows?

Apart from platforms such as the K3, Orion or ADT-200A? hi hi

Maybe these will help:

<http://www.olifantasia.com/gnuradio/gnuradio_links.html>
<http://hpsdr.org/>
<http://uk.groups.yahoo.com/group/picastar/>
<http://dttsp.sourceforge.net/>

vy 73 de toby

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dave.wilburn

Re: Comparison: K3 and SDR 5000A

Thanks

David Wilburn
[hidden email]
K4DGW
K2 #5982
FP#-1751

Toby Deinhardt wrote:

>> Has anyone made an SDR yet that runs on anything but windows?
>
> Apart from platforms such as the K3, Orion or ADT-200A? hi hi
>
>
> Maybe these will help:
>
> <http://www.olifantasia.com/gnuradio/gnuradio_links.html>
> <http://hpsdr.org/>
> <http://uk.groups.yahoo.com/group/picastar/>
> <http://dttsp.sourceforge.net/>
>
>
> vy 73 de toby
>
>
>

Richard Smith-23

Re: Comparison: K3 and SDR 5000A

In reply to this post by Bill W4ZV

Hi Bill,

I would like to balance the scales here a little bit. First of all, I am
not only an Elecraft fan, but a Flex-Radio fan as well. I own a K2 as well
as an SDR-1000. I love what all these guys have done for Amateur Radio in
the past few years. We are all the beneficiaries of their excellent
engineering and competitive spirits.

After some long and hard thinking, I chose the SDR-5000A over the K3. I
think the specs are very close and either rig will do better than anything
I've ever owned before, including the K2, the SDR-1000 and an Icom 756PRO.
And all of those rigs were more than adequate in my location. Of course,
your mileage and mission may vary. I think the K3 and 5000A will both blow
away the Icom - Yaesu competition costing many thousands more.

I think your cost analysis is a bit overstated. I don't understand why Flex
Radio priced the 5000C so high. I think a fairer comparison is with the
5000A plus a stand alone computer. I imagine that most hams would be able
to use the computer currently in their shack. I upgraded mine to a dual
core AMD Athlon 64 X2 by throwing in a new motherboard, etc. for a few
hundred dollars when I got the SDR-1000. The CPU runs at less than 20% when
running the SDR-1000 full bore. For the $600 you mention for a PC, you can
get more than enough machine off the shelf to run an SDR-5000A plus
everything else in the shack simultaneously (e.g., logging program, PSK-31,
etc.). So now the calculation looks like:

SDR-5000A $2799
Computer $600

Total $3399, not $5098. I don't think you need the $99
knob.

In my case I already have the computer, and I bought the radio just
before the October 1 price increase, so my cost is $2499, or actually $2798
with the ATU.

Ergonomically, I must say that I really like the computer GUI of the
PowerSDR. I was skeptical at first, and was reluctant to give up my knobs,
but I don't even reach for them anymore. Tuning is very smooth with a
mousewheel, and its very easy to "reach" for other programs on the screen
while operating by just simply moving the mouse. I also like the fact that
you can connect various programs to the PowerSDR program through virtual
audio and port connections - that is you can, for instance interface a PSK31
program to the radio audio and com port without any cables, etc. You can
have many such channels running simultaneously. The radio should also
improve over time as the software continues to evolve. Very cool.

But most of all for me, its about the bandscope. I got hooked by the
756PRO, and the SDR-1000 brought my addiction to a whole other level. Its
not just seeing, its doing. Point and click tuning. Point and drag tuning.
Visual bandedge filter adjustments by dragging an edge. Etc. For me, this
was the key deciding factor for going with the SDR-5000A rather than the K3,
where to me, the other specs are very close.

But in a perfect world, I'd own both.

73,

Rich W1EZ

----- Original Message -----
From: "Bill Tippett" <[hidden email]>
To: <[hidden email]>
Sent: Saturday, October 06, 2007 3:52 PM
Subject: [Elecraft] Comparison: K3 and SDR 5000A

> Form Factor:
>
> This is a religious issue with some. Knobs versus
> no knobs. "Real Radios Don't Need Knobs" (Flex's slogan).
> I suppose the K3's corollary slogan is "Real Radios Don't
> Need Computers". :-)
>
>
> Cost (for the 5000 it depends on whether you already have
> a fairly high-performance computer dedicated to your shack.
> I'm going to compare the 5000C which includes the computer
> and will assume $200 for an LCD display):
>
> 5000C $5098 (no ATU, $200 display plus a $99 knob option)
> K3 $2825 (assembled K3/100, KXV3, KRX3, 2X 500 Hz filters)
>
> Of course the K3 does not include a bandscope, but the KXV3
> provides the wide bandwidth buffered IF output to do this.
> Eventually Elecraft, Clifton Labs or someone will provide
> this. The solution could be as simple as a SoftRock40 on
> the 8.215 MHz output to something much more exotic. Let's
> assume $400 for something like a Clifton Labs Z91 plus
> another $600 for an adequate computer and display, resulting
> in an additional $1000 for interface hardware, computer and
> display. I'm assuming free software based either on Rocky
> or PowerSDR. This results in:
>
> 5000C $5098
> K3+ $3825
>
> Advantage: K3 which will have basic RX performance
> exceeding the 5000 (see above) and a parallel SDR bandscope.
> Assuming someone like HB9DRV integrates this with his Ham
> Radio Deluxe program, I believe the K3 will maintain a
> significant price advantage over the 5000C.
>
>
> 73, Bill W4ZV
>
>
>
>
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
> http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com

Bill W4ZV

Fwd: Comparison: K3 and SDR 5000A

Hi Richard,

W1EZ wrote:

> Hi Bill,
>
> I would like to balance the scales here a little bit. First of all, I am
> not only an Elecraft fan, but a Flex-Radio fan as well. I own a K2 as well
> as an SDR-1000. I love what all these guys have done for Amateur Radio in
> the past few years. We are all the beneficiaries of their excellent
> engineering and competitive spirits.

And add excellent customer responsiveness by both companies
through forums like this! Ten-Tec is also much more responsive than
the Big 3.

> After some long and hard thinking, I chose the SDR-5000A over the K3. I
> think the specs are very close and either rig will do better than anything
> I've ever owned before, including the K2, the SDR-1000 and an Icom 756PRO.
> And all of those rigs were more than adequate in my location. Of course,
> your mileage and mission may vary. I think the K3 and 5000A will both blow
> away the Icom - Yaesu competition costing many thousands more.
>
> I think your cost analysis is a bit overstated. I don't understand why Flex
> Radio priced the 5000C so high. I think a fairer comparison is with the
> 5000A plus a stand alone computer. I imagine that most hams would be able
> to use the computer currently in their shack. I upgraded mine to a dual
> core AMD Athlon 64 X2 by throwing in a new motherboard, etc. for a few
> hundred dollars when I got the SDR-1000. The CPU runs at less than 20% when
> running the SDR-1000 full bore. For the $600 you mention for a PC, you can
> get more than enough machine off the shelf to run an SDR-5000A plus
> everything else in the shack simultaneously (e.g., logging program, PSK-31,
> etc.). So now the calculation looks like:
>
> SDR-5000A $2799
> Computer $600
>
> Total $3399, not $5098. I don't think you need the $99
> knob.
>
> In my case I already have the computer, and I bought the radio just
> before the October 1 price increase, so my cost is $2499, or actually $2798
> with the ATU.

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.

> Ergonomically, I must say that I really like the computer GUI of the
> PowerSDR. I was skeptical at first, and was reluctant to give up my knobs,
> but I don't even reach for them anymore. Tuning is very smooth with a
> mousewheel, and its very easy to "reach" for other programs on the screen
> while operating by just simply moving the mouse. I also like the fact that
> you can connect various programs to the PowerSDR program through virtual
> audio and port connections - that is you can, for instance interface a PSK31
> program to the radio audio and com port without any cables, etc. You can
> have many such channels running simultaneously. The radio should also
> improve over time as the software continues to evolve. Very cool.

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.

> But most of all for me, its about the bandscope. I got hooked by the
> 756PRO, and the SDR-1000 brought my addiction to a whole other level. Its
> not just seeing, its doing. Point and click tuning. Point and drag tuning.
> Visual bandedge filter adjustments by dragging an edge. Etc. For me, this
> was the key deciding factor for going with the SDR-5000A rather than the K3,
> where to me, the other specs are very close.
>
> 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.

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'm sure both rigs will do well in their respective niches and
we are indeed fortunate to have two such responsive companies
challenging the Big 3. Thanks for your comments which I'm sure are
representative of many other folks. As they say, "That's what makes a
market"...in the end, customers will decide.

73, Bill W4ZV
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Brett gazdzinski-2

RE: Comparison: K3 and SDR 5000A

The flex radio is making big strides into the AM community,
because it allows better then broadcast quality audio on TX, or
communications quality , or anything in-between, and also allows
tricks with the modulation, negative clipping, compression, EQ,
very good fidelity reception, and of course the band scope feature.

I am not fond of computers in the shack, don't contest or DX,
but the flex stuff is starting to look very interesting to me.
The 5000D? will have true diversity reception and 300 watts pep output,
computer built in, auto antenna tuner, built in power supply, and all
sorts of other new things they will think up in the software...

Not sure what it will cost, but it looks like it will do whatever you
want to do in radio.

It sure would be an odd mix in my shack, with all the
homebrew vacuum tube stuff!

Brett
N2DTS

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Richard Smith-23

Re: Comparison: K3 and SDR 5000A

In reply to this post by Bill W4ZV

> 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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Joe Subich, W4TV

RE: Comparison: K3 and SDR 5000A

> 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.

Since Power SDR has a Kenwood CAT interface, I would bet it would
relatively easy to couple PowerSDR with a SoftRock40, a relatively
inexpensive soundcard and a few lines of custom software to both
provide a "bandscope" and fully control the K3.

If one is into the GUI interface, such a configuration would
provide a real receiver with proper filtering close to the antenna
and still have all the point and click control one might want.

73,

... Joe, W4TV

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Darwin, Keith

RE: Comparison: K3 and SDR 5000A

In reply to this post by Richard Smith-23

-----Original Message-----
From: Richard Smith

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?
-------------------------

Rich has a very good point here. There is a tremendous momentum to "the
way things have been". Basically, most of us are resistant to change.
We're happy to have the new provided it looks / feels / works just like
the old.

But people can change and relearn. Those that go through the difficult
process will often find that the new way is just as intuitive as the old
and provides capabilities that the old way couldn't even dream about.

When was the last time you played solitaire with a real deck of cards?
For many of us, that game has become a Windows application and we
happily play it with a mouse, not really missing the old way we used to
play the game.

- Keith N1AS -
- K2 5411.ssb.100 -

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John A. McCabe

Re: Comparison: K3 and SDR 5000A

In reply to this post by Richard Smith-23

Hi All

"Since Power SDR has a Kenwood CAT interface, I would bet it would
relatively easy to couple PowerSDR with a SoftRock40, a relatively
inexpensive soundcard and a few lines of custom software to both provide
a "bandscope" and fully control the K3"

There already is a modified version of PowerSDR that is similar to what
you are describing. It is a version that works with Ham Radio Deluxe and
a Softrock to allow point and click bandscope tuning in PowerSDR of any
radio that has an IF out (which includes the K3) and supported by Ham
Radio Deluxe. I have tried it and it does work (Not on a K3 however,
still waiting on mine like the rest of us). To me this is the best of
both worlds, a High performance K3 controlled by computer and/or Knobs.
Sometimes I just don't want to have to boot my computer up to use my
radio, and at other times the features of bandscope point and click
tuning would be nice.

The software is at the following location: http://www.wu2x.com/sdr.html

73, John KD8K

>
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Richard Thorne

Re: Comparison: K3 and SDR 5000A

In reply to this post by Darwin, Keith

It all depends on the use of the rig. If the rig is for contesting then
more than likely one will want knobs. You wouldn't want to be jumping
around with your mouse between software applications (contest software,
rig control software). Its not very efficient.

Rich - N5ZC

Darwin, Keith wrote:

> -----Original Message-----
> From: Richard Smith
>
> 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?
> -------------------------
>
> Rich has a very good point here. There is a tremendous momentum to "the
> way things have been". Basically, most of us are resistant to change.
> We're happy to have the new provided it looks / feels / works just like
> the old.
>
> But people can change and relearn. Those that go through the difficult
> process will often find that the new way is just as intuitive as the old
> and provides capabilities that the old way couldn't even dream about.
>
> When was the last time you played solitaire with a real deck of cards?
> For many of us, that game has become a Windows application and we
> happily play it with a mouse, not really missing the old way we used to
> play the game.
>
> - Keith N1AS -
> - K2 5411.ssb.100 -
>
> _______________________________________________
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> Post to: [hidden email]
> You must be a subscriber to post to the list.
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>
>
>

Richard Smith-23

Re: Comparison: K3 and SDR 5000A

In reply to this post by John A. McCabe

Thanks for the info on this program, John. I'll download it and give it a
try.

My first reaction without trying the program (always dangerous) is that
needing HRD sitting between the PowerSDR GUI and the K3, and controlling the
K3 via serial commands, will leave users with the feeling that software
control just isn't responsive enough for real world uses. To me, even a
slight delay in response, or waiting for the rig to catch up with the GUI
user, is annoying enough for me to reach for the knobs. It certainly won't
cut it for competitive contesting. The PowerSDR when used with the
SDR-1000, and I assume the SDR-5000A as well, has an instantaneous "feel" to
the software. It feels very natural to tune, and no adjustment is necessary
by the user to learn how to use it effectively. It is a generation beyond
what you propose in software control. My beef with serial
command-controlled hardware radios has always been the tuning "lag" I
experience as I sweep the software controls up and down the band and the
radio tries to keep up. That is not the case with the PowerSDR running the
SDR-1000 or 5000A. Maybe the K3, the interface, the software and the PC
will all be responsive enough to emulate the excellent "feel" of the
PowerSDR running an SDR-5000A, but I'm skeptical it will. Right now, this
solution seems like a band-aid to me.

Also, is booting a computer really an issue? I use mine these days for so
many things, it is always on or in standby. I can play radio at anytime by
simply clicking the PowerSDR icon.

It will be interesting to see how things evolve.

73,

Rich W1EZ

----- Original Message -----
From: "John A. McCabe" <[hidden email]>
Cc: <[hidden email]>
Sent: Tuesday, October 09, 2007 7:34 AM
Subject: Re: [Elecraft] Comparison: K3 and SDR 5000A

> Hi All
>
> "Since Power SDR has a Kenwood CAT interface, I would bet it would
> relatively easy to couple PowerSDR with a SoftRock40, a relatively
> inexpensive soundcard and a few lines of custom software to both provide a
> "bandscope" and fully control the K3"
>
>
> There already is a modified version of PowerSDR that is similar to what
> you are describing. It is a version that works with Ham Radio Deluxe and a
> Softrock to allow point and click bandscope tuning in PowerSDR of any
> radio that has an IF out (which includes the K3) and supported by Ham
> Radio Deluxe. I have tried it and it does work (Not on a K3 however,
> still waiting on mine like the rest of us). To me this is the best of both
> worlds, a High performance K3 controlled by computer and/or Knobs.
> Sometimes I just don't want to have to boot my computer up to use my
> radio, and at other times the features of bandscope point and click tuning
> would be nice.
>
> The software is at the following location: http://www.wu2x.com/sdr.html
>
> 73, John KD8K
>
>
>
>
>
>>
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
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wayne burdick

PC->K3 command responsiveness

Administrator

Richard Smith wrote:

> My first reaction without trying the program (always dangerous) is
> that needing HRD sitting between the PowerSDR GUI and the K3, and
> controlling the K3 via serial commands, will leave users with the
> feeling that software control just isn't responsive enough for real
> world uses.

Richard,

The K3 serial I/O port can run at up to 38.4 kb, and command response
is very fast. It can also buffer a large number of commands at full
speed and respond to them in order, error-free. To verify this, I'll
paste 10 different commands into the terminal emulator window, running
at 38.4 kb. All 10 responses appear in the terminal emulator window
immediately, with no perceptible delay.

Yesterday there was a discussion about Panadapter responsiveness.
If/when we offer a panadapter, it will be tightly linked with the K3,
so you'll be able to do things like click on a signal and move the VFO
to it, etc. If the text decoder is turned on, CW, RTTY, and PSK31
signals will be decoded and displayed on the K3's own LCD and/or in a
window on the panadapter.

Of course the "P3" would match the K3's enclosure styling, too, and may
include a power supply and/or speaker. For field ops, you could take
just the K3. Either way, it's computer-optional.

73,
Wayne
N6KR

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John A. McCabe

Re: Comparison: K3 and SDR 5000A

In reply to this post by Richard Smith-23

Hi Rich,

Actually, and correct me if I am wrong on this, but I believe that one
of the bigger issues with SDR's right now is with latency. There is some
delay in the processing of the signal on the computer which can cause
effects such as slower turn around time for CW/Digtal Modes, slightly
slower tuning, a slight delay in received and transmitted audio, etc. I
know there has been a lot of improvement made in that area, but I don't
believe it is quite at the level of other radios such as the K3. .
Whether or not this latency is more or less more then serial control of
a radio, I am not sure. But I suspect that some of that might depend on
the baud rate of the radio. I have a TS-2000 set to 57600 baud and it
seems quite responsive, whereas my K2 which I believe is 4800 baud is
noticeably less responsive. I am not sure what the baud rate is on the
K3. And as far as booting up a computer, I work as a computer
consultant, and sometimes the last thing I want to do when I get home
from work is boot up my computer :)

John, KD8K

Richard Smith wrote:

> Thanks for the info on this program, John. I'll download it and give
> it a try.
>
> My first reaction without trying the program (always dangerous) is
> that needing HRD sitting between the PowerSDR GUI and the K3, and
> controlling the K3 via serial commands, will leave users with the
> feeling that software control just isn't responsive enough for real
> world uses. To me, even a slight delay in response, or waiting for
> the rig to catch up with the GUI user, is annoying enough for me to
> reach for the knobs. It certainly won't cut it for competitive
> contesting. The PowerSDR when used with the SDR-1000, and I assume
> the SDR-5000A as well, has an instantaneous "feel" to the software.
> It feels very natural to tune, and no adjustment is necessary by the
> user to learn how to use it effectively. It is a generation beyond
> what you propose in software control. My beef with serial
> command-controlled hardware radios has always been the tuning "lag" I
> experience as I sweep the software controls up and down the band and
> the radio tries to keep up. That is not the case with the PowerSDR
> running the SDR-1000 or 5000A. Maybe the K3, the interface, the
> software and the PC will all be responsive enough to emulate the
> excellent "feel" of the PowerSDR running an SDR-5000A, but I'm
> skeptical it will. Right now, this solution seems like a band-aid to me.
>
> Also, is booting a computer really an issue? I use mine these days
> for so many things, it is always on or in standby. I can play radio
> at anytime by simply clicking the PowerSDR icon.
>
> It will be interesting to see how things evolve.
>
> 73,
>
> Rich W1EZ
>
> ----- Original Message ----- From: "John A. McCabe"
> <[hidden email]>
> Cc: <[hidden email]>
> Sent: Tuesday, October 09, 2007 7:34 AM
> Subject: Re: [Elecraft] Comparison: K3 and SDR 5000A
>
>
>> Hi All
>>
>> "Since Power SDR has a Kenwood CAT interface, I would bet it would
>> relatively easy to couple PowerSDR with a SoftRock40, a relatively
>> inexpensive soundcard and a few lines of custom software to both
>> provide a "bandscope" and fully control the K3"
>>
>>
>> There already is a modified version of PowerSDR that is similar to
>> what you are describing. It is a version that works with Ham Radio
>> Deluxe and a Softrock to allow point and click bandscope tuning in
>> PowerSDR of any radio that has an IF out (which includes the K3) and
>> supported by Ham Radio Deluxe. I have tried it and it does work
>> (Not on a K3 however, still waiting on mine like the rest of us). To
>> me this is the best of both worlds, a High performance K3 controlled
>> by computer and/or Knobs. Sometimes I just don't want to have to boot
>> my computer up to use my radio, and at other times the features of
>> bandscope point and click tuning would be nice.
>>
>> The software is at the following location: http://www.wu2x.com/sdr.html
>>
>> 73, John KD8K
>>
>>
>>
>>
>>
>>>
>> _______________________________________________
>> Elecraft mailing list
>> Post to: [hidden email]
>> You must be a subscriber to post to the list.
>> Subscriber Info (Addr. Change, sub, unsub etc.):
>> http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/subscribers.htm
>> Elecraft web page: http://www.elecraft.com
>
>
>

n6wg

Re: PC->K3 command responsiveness

In reply to this post by wayne burdick

Wayne
Does the use of the mouse to click imply a computer,
or some uP likely to be imbedded in the Pan'r?
Running TRLOG in DOS doesn't leave me with a
mouse to click on things.
73, Bob N6WG

----- Original Message -----
From: "wayne burdick" <[hidden email]>
To: "Richard Smith" <[hidden email]>
Cc: "Elecraft Reflector" <[hidden email]>
Sent: Tuesday, October 09, 2007 9:25 AM
Subject: [Elecraft] PC->K3 command responsiveness

> Richard Smith wrote:
>
> > My first reaction without trying the program (always dangerous) is
> > that needing HRD sitting between the PowerSDR GUI and the K3, and
> > controlling the K3 via serial commands, will leave users with the
> > feeling that software control just isn't responsive enough for real
> > world uses.
>
> Richard,
>
> The K3 serial I/O port can run at up to 38.4 kb, and command response
> is very fast. It can also buffer a large number of commands at full
> speed and respond to them in order, error-free. To verify this, I'll
> paste 10 different commands into the terminal emulator window, running
> at 38.4 kb. All 10 responses appear in the terminal emulator window
> immediately, with no perceptible delay.
>
> Yesterday there was a discussion about Panadapter responsiveness.
> If/when we offer a panadapter, it will be tightly linked with the K3,
> so you'll be able to do things like click on a signal and move the VFO
> to it, etc. If the text decoder is turned on, CW, RTTY, and PSK31
> signals will be decoded and displayed on the K3's own LCD and/or in a
> window on the panadapter.
>
> Of course the "P3" would match the K3's enclosure styling, too, and may
> include a power supply and/or speaker. For field ops, you could take
> just the K3. Either way, it's computer-optional.
>
> 73,
> Wayne
> N6KR
>
> _______________________________________________
> Elecraft mailing list
> Post to: [hidden email]
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
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>
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Richard Smith-23

Re: PC->K3 command responsiveness

In reply to this post by wayne burdick

Thanks for your response Wayne. The P3 approach sounds like the way to go,
and I look forward to seeing it. My concern is that some of the patchwork
solutions being discussed just won't cut it.

There may be a K3 in my future yet.

73,

Rich W1EZ
----- Original Message -----
From: "wayne burdick" <[hidden email]>
To: "Richard Smith" <[hidden email]>
Cc: "Elecraft Reflector" <[hidden email]>; "John A. McCabe"
<[hidden email]>
Sent: Tuesday, October 09, 2007 12:25 PM
Subject: PC->K3 command responsiveness

> Richard Smith wrote:
>
>> My first reaction without trying the program (always dangerous) is that
>> needing HRD sitting between the PowerSDR GUI and the K3, and controlling
>> the K3 via serial commands, will leave users with the feeling that
>> software control just isn't responsive enough for real world uses.
>
> Richard,
>
> The K3 serial I/O port can run at up to 38.4 kb, and command response is
> very fast. It can also buffer a large number of commands at full speed and
> respond to them in order, error-free. To verify this, I'll paste 10
> different commands into the terminal emulator window, running at 38.4 kb.
> All 10 responses appear in the terminal emulator window immediately, with
> no perceptible delay.
>
> Yesterday there was a discussion about Panadapter responsiveness. If/when
> we offer a panadapter, it will be tightly linked with the K3, so you'll be
> able to do things like click on a signal and move the VFO to it, etc. If
> the text decoder is turned on, CW, RTTY, and PSK31 signals will be decoded
> and displayed on the K3's own LCD and/or in a window on the panadapter.
>
> Of course the "P3" would match the K3's enclosure styling, too, and may
> include a power supply and/or speaker. For field ops, you could take just
> the K3. Either way, it's computer-optional.
>
> 73,
> Wayne
> N6KR
>

Richard Smith-23

Re: Comparison: K3 and SDR 5000A

In reply to this post by John A. McCabe

Hi John,

As I understand it, latency is no longer an issue. Latency issues with the
early versions of PowerSDR and the SDR-1000 have been resolved. That being
said, signal processing latency is a fact of life for all digital radios.
We are talking microseconds, and I don't think its fair to say that the
performance of the SDR-5000A will be inferior in this respect to other
radios such as the K3. PCs are pretty damn fast processors these days. I
think the much slower serial control commands are more significant in
dictating the feel of the software controlled radio than the signal
processing latency.

73,

Rich W1EZ

----- Original Message -----
From: "John A. McCabe" <[hidden email]>
Cc: <[hidden email]>
Sent: Tuesday, October 09, 2007 12:53 PM
Subject: Re: [Elecraft] Comparison: K3 and SDR 5000A

> Hi Rich,
>
> Actually, and correct me if I am wrong on this, but I believe that one of
> the bigger issues with SDR's right now is with latency. There is some
> delay in the processing of the signal on the computer which can cause
> effects such as slower turn around time for CW/Digtal Modes, slightly
> slower tuning, a slight delay in received and transmitted audio, etc. I
> know there has been a lot of improvement made in that area, but I don't
> believe it is quite at the level of other radios such as the K3. . Whether
> or not this latency is more or less more then serial control of a radio, I
> am not sure. But I suspect that some of that might depend on the baud rate
> of the radio. I have a TS-2000 set to 57600 baud and it seems quite
> responsive, whereas my K2 which I believe is 4800 baud is noticeably less
> responsive. I am not sure what the baud rate is on the K3. And as far as
> booting up a computer, I work as a computer consultant, and sometimes the
> last thing I want to do when I get home from work is boot up my computer
> :)
>
> John, KD8K
>
>

KK7P

Re: Comparison: K3 and SDR 5000A

> As I understand it, latency is no longer an issue. Latency issues with
> the early versions of PowerSDR and the SDR-1000 have been resolved.
> That being said, signal processing latency is a fact of life for all
> digital radios. We are talking microseconds,

I beg to differ.

Latency (delay) in a DSP-based radio (or SDR, if you prefer) is caused
by several things.

The one we can't get rid of is the filter delay. By making "shorter"
filters (fewer taps), we can reduce the delay through the filter, but at
the expense of filter performance. We get wider skirts, less ultimate
rejection, more passband ripple, or some combination of these three factors.

However, DSP can be applied in many ways. One sure way to increase
latency is by processing the incoming signal in blocks. This means you
collect a certain number of samples, then process them all at once while
collecting the next block, etc. PC implementations of DSP typically use
this method.

Another method is to process the signal after each sample. This
eliminates the block delay. This is how the K3 processes signals.

As an example, let's consider an SDR using 2048-sample blocks (common in
the SDR world) and 96 kHz sampling. It will take (2048/96,000 =) 22
milliseconds to acquire this block. This is 22 ms more delay, or
latency, than a K3 will have, assuming similar delays in each radio for
the filter(s).

For a real world example, I connected an SDR-14 receiver (with
associated dual core 3 GHz PC) to the IF output of my K3. I then tuned
in an SSB signal and listened to it through the K3's speaker as well as
demodulating it and listening through the PC's audio system.

The audio coming from the PC was very noticeably delayed versus the
audio from the K3.

This delay or latency may not be an issue in all cases. But in come
common operational scenarios, like QSK CW or SSB using "syllabic" VOX,
it can be critical. By paying close attention to such latency issues in
the architecture of the K3, we are able to provide QSK CW operation at
speeds well over 30 WPM without "reducing the taps" in the filters or
otherwise compromising the performance of the radio. The 22 ms
additional delay cited in the example above would kill QSK performance.

Latency is just one of many considerations that arise when comparing
radios, architectures, and one's own needs and preferences.

73,

Lyle KK7P

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Richard Smith-23

Re: Comparison: K3 and SDR 5000A

Lyle,

I don't believe you can get something for nothing. The sample-in/sample-out
may work at steady state, but if you use an FIR filter, it still takes a
number of samples and time to fill the filter pipeline, as well as empty it.
My DSP may be a bit rusty, but I believe that the edges of a CW signal (the
no-signal to signal transition and the signal to no-signal transition) still
takes time to propogate through the FIR filter, and appears as a signal
delayed in time at the output. What is it about the K3 architecture that
eliminates this latency? How many taps does the FIR filter have that is
used in the K3 for a 30 WPM QSK mode, and what is the sample rate of the A/D
in that mode?

73,

Rich W1EZ
----- Original Message -----
From: "Lyle Johnson" <[hidden email]>
To: <[hidden email]>
Sent: Wednesday, October 10, 2007 2:13 AM
Subject: Re: [Elecraft] Comparison: K3 and SDR 5000A

>> As I understand it, latency is no longer an issue. Latency issues with
>> the early versions of PowerSDR and the SDR-1000 have been resolved. That
>> being said, signal processing latency is a fact of life for all digital
>> radios. We are talking microseconds,
>
> I beg to differ.
>
> Latency (delay) in a DSP-based radio (or SDR, if you prefer) is caused by
> several things.
>
> The one we can't get rid of is the filter delay. By making "shorter"
> filters (fewer taps), we can reduce the delay through the filter, but at
> the expense of filter performance. We get wider skirts, less ultimate
> rejection, more passband ripple, or some combination of these three
> factors.
>
> However, DSP can be applied in many ways. One sure way to increase
> latency is by processing the incoming signal in blocks. This means you
> collect a certain number of samples, then process them all at once while
> collecting the next block, etc. PC implementations of DSP typically use
> this method.
>
> Another method is to process the signal after each sample. This
> eliminates the block delay. This is how the K3 processes signals.
>
> As an example, let's consider an SDR using 2048-sample blocks (common in
> the SDR world) and 96 kHz sampling. It will take (2048/96,000 =) 22
> milliseconds to acquire this block. This is 22 ms more delay, or latency,
> than a K3 will have, assuming similar delays in each radio for the
> filter(s).
>
> For a real world example, I connected an SDR-14 receiver (with associated
> dual core 3 GHz PC) to the IF output of my K3. I then tuned in an SSB
> signal and listened to it through the K3's speaker as well as demodulating
> it and listening through the PC's audio system.
>
> The audio coming from the PC was very noticeably delayed versus the audio
> from the K3.
>
> This delay or latency may not be an issue in all cases. But in come
> common operational scenarios, like QSK CW or SSB using "syllabic" VOX, it
> can be critical. By paying close attention to such latency issues in the
> architecture of the K3, we are able to provide QSK CW operation at speeds
> well over 30 WPM without "reducing the taps" in the filters or otherwise
> compromising the performance of the radio. The 22 ms additional delay
> cited in the example above would kill QSK performance.
>
> Latency is just one of many considerations that arise when comparing
> radios, architectures, and one's own needs and preferences.
>
> 73,
>
> Lyle KK7P
>
>
>
>
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