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SDR IQ/IF Questions

AB3LS
Hello fellow SDR enthusiasts,

 

I have looked around a little bit and haven't found a very definitive answer
for the questions that I'm having about the way the K3 and external SDR
equipment works.

 

I've been looking into the LP-Pan which converts the IF output from the K3
into (im guessing) audio signals which then are converted into digital data
by a soundcard. The trouble I'm having is understanding what exactly I/Q is.
>From what I understand, I/Q is digital data that software like CW Skimmer
understands.

 

Now, I've also been looking at the SDR-IQ which does all of this internally
by taking the IF output from the K3 and converts it directly into digital
data which is then ferried to the computer over USB, forgoing the need for
an extra soundcard.

 

Now, I've seen two versions of PowerSDR. I've seen PowerSDR/IF (looks more
developed/supported), and PowerSDR-IQ. What is the difference?

 

I suppose the summary question of this email is. can you use PowerSDR/IF
with an SDR-IQ rather than an LP-Pan? I personally would rather buy an
SDR-IQ and take that extra hardware stage (possible audio loss) out of the
picture.

 

Thanks!

 

Geoffrey Wolf

AB3LS - Amateur Radio Callsign

University of Pittsburgh '14

[hidden email]

[hidden email]

(412) 450-1310

 

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Geoffrey Wolf
AB3LS
University of Pittsburgh '14
grw20@pitt.edu
liltechdude13@gmail.com
http://www.ab3ls.com
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Re: SDR IQ/IF Questions

AB3LS
Okay,

Well thank you for the link. I have a little bit of reading up to do on I/Q.
So I'm still a little bit confused in the K3 setup situation. So in both the
situations with the LP-Pan or the SDR-IQ, the PowerSDR software would
receive the same data? I'm having trouble understanding where the analog
signals are converted into digital signals. In the case of the LP-Pan, I'm
imagining that it happens at the soundcard? In the case of the SDR-IQ, it
takes place inside the SDR-IQ... right?

Sorry for my misunderstanding here...

So my main question still stands, can you use PowerSDR/IF software with an
SDR-IQ?

Thank You!

Geoffrey Wolf
AB3LS - Amateur Radio Callsign
University of Pittsburgh '14
[hidden email]
[hidden email]
(412) 450-1310

> -----Original Message-----
> From: [hidden email] [mailto:[hidden email]]
> Sent: Wednesday, April 06, 2011 1:39 PM
> To: Geoffrey Wolf
> Subject: Re: [Elecraft] SDR IQ/IF Questions
>
> Read this...
> http://education.tm.agilent.com/index.cgi?CONTENT_ID=4
>
>
>
>
>


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Geoffrey Wolf
AB3LS
University of Pittsburgh '14
grw20@pitt.edu
liltechdude13@gmail.com
http://www.ab3ls.com
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Re: SDR IQ/IF Questions

Byron Servies
In reply to this post by AB3LS
Hi Geoffrey,

Perhaps the ARRL Handbook, Chapter 15 - "DSP and Software Radio
Design", might help? Section 15.6, in particular describes the math
behind calculating the in-phase (I) and quadrature (Q) portions of a
wave form.

As for specific device compatibility with particular software
packages, the release notes for the software should list the hardware
it will work with.

HTH,

On Wed, Apr 6, 2011 at 10:29 AM, Geoffrey Wolf <[hidden email]> wrote:

> I've been looking into the LP-Pan which converts the IF output from the K3
> into (im guessing) audio signals which then are converted into digital data
> by a soundcard. The trouble I'm having is understanding what exactly I/Q is.
> >From what I understand, I/Q is digital data that software like CW Skimmer
> understands.

73, Byron N6NUL
----
- Northern California Contest Club
- CU in the 2011 Cal QSO Party 1-2 Oct 2011
- www.cqp.org
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Re: SDR IQ/IF Questions

AB3LS
Oh thank you. I Have the handbook but didn't know there was a DSP section. I'll take a look at that.

--------------
Geoffrey Wolf
AB3LS (Amateur Radio Callsign)
University of Pittsburgh '14
[hidden email]
[hidden email]
(412) 450-1310


On Apr 6, 2011, at 2:07 PM, Byron Servies <[hidden email]> wrote:

> Hi Geoffrey,
>
> Perhaps the ARRL Handbook, Chapter 15 - "DSP and Software Radio
> Design", might help? Section 15.6, in particular describes the math
> behind calculating the in-phase (I) and quadrature (Q) portions of a
> wave form.
>
> As for specific device compatibility with particular software
> packages, the release notes for the software should list the hardware
> it will work with.
>
> HTH,
>
> On Wed, Apr 6, 2011 at 10:29 AM, Geoffrey Wolf <[hidden email]> wrote:
>
>> I've been looking into the LP-Pan which converts the IF output from the K3
>> into (im guessing) audio signals which then are converted into digital data
>> by a soundcard. The trouble I'm having is understanding what exactly I/Q is.
>>> From what I understand, I/Q is digital data that software like CW Skimmer
>> understands.
>
> 73, Byron N6NUL
> ----
> - Northern California Contest Club
> - CU in the 2011 Cal QSO Party 1-2 Oct 2011
> - www.cqp.org
______________________________________________________________
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Geoffrey Wolf
AB3LS
University of Pittsburgh '14
grw20@pitt.edu
liltechdude13@gmail.com
http://www.ab3ls.com
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Re: SDR IQ/IF Questions

Leigh L. Klotz Jr WA5ZNU
Administrator
In reply to this post by AB3LS
If you're interested in DSP code you might try using quisk instead of PowerSDR.
It's written in mostly Python and a little bit of C, and works on Linux and Windows.
I made some modules for it to talk to the K3 rigcontrol, but those aren't necessary to use it with the LP-PAN output, just for the click-to-qsy and frequency display.

Leigh/WA5ZNU
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(phase signals RE: SDR IQ/IF Questions

George Thornton
In reply to this post by AB3LS
IQ data is a method for describing the characteristics of a wave.  IQ
uses amplitude and phase angle to describe the wave, see for example

 http://zone.ni.com/devzone/cda/tut/p/id/3013

The K3 takes an RF signal from an antenna, filters and modulates it.  At
some point the filtered, modulated signal is made available to an IF out
port where it can be used conveniently by various testing and measuring
devices.

A panadapter takes the IF signal and converts it into IQ signals.  These
IQ signals can then be used to visually represent characteristics of the
signal on a chart or screen.  The LP-pan converts the I and Q signals to
audio for input into a computer using a sound card.  The P3 panadapter
directly charts the IQ data onto the built in screen.

The SDR-IQ is a standalone software designed receiver.  It is designed
to hook directly into an antenna source and can be used with software to
directly display data about the signal.  I do not believe it is designed
to work with modulated IF output from a quality receiver, but I could be
wrong.

The SDR-IQ can be used as a standalone panadapter through a computer,
getting its signal direct from the antenna, completely bypassing the
transceiver altogether.  According to its own manual it does not have
much filtering and it can get overwhelmed by other RF sources.  

The price for the LP-Pan and sound card is less than the price for the
SDR-IQ.  The P3 costs only a small amount more than the SDR-IQ.

The P3 and LP-Pan were compared in a recent QST article.  According to
the testers, the two approaches are roughly equal in their ability to
decode and display weak signals.  

The LP-Pan has the advantage of allowing the use of a large computer
screen for a panadapter. The disadvantage is that it is complex to set
up, requires use of buggy computers and software with driver
compatibility issues and has a lot of loose wiring.  

The P3 is a plug and play solution that is reliable and easy to use. The
P3 is more closely integrated with the K3.  IN the future the P3 is
going to allow direct connection to a computer monitor and keyboard.

Given all the factors, I do not think the SDR-IQ solution is the best
choice here.



From: [hidden email]
[mailto:[hidden email]] On Behalf Of Geoffrey Wolf
Sent: Wednesday, April 06, 2011 10:30 AM
To: [hidden email]
Subject: [Elecraft] SDR IQ/IF Questions

Hello fellow SDR enthusiasts,

 

I have looked around a little bit and haven't found a very definitive
answer
for the questions that I'm having about the way the K3 and external SDR
equipment works.

 

I've been looking into the LP-Pan which converts the IF output from the
K3
into (im guessing) audio signals which then are converted into digital
data
by a soundcard. The trouble I'm having is understanding what exactly I/Q
is.
>From what I understand, I/Q is digital data that software like CW
Skimmer
understands.

 

Now, I've also been looking at the SDR-IQ which does all of this
internally
by taking the IF output from the K3 and converts it directly into
digital
data which is then ferried to the computer over USB, forgoing the need
for
an extra soundcard.

 

Now, I've seen two versions of PowerSDR. I've seen PowerSDR/IF (looks
more
developed/supported), and PowerSDR-IQ. What is the difference?

 

I suppose the summary question of this email is. can you use PowerSDR/IF
with an SDR-IQ rather than an LP-Pan? I personally would rather buy an
SDR-IQ and take that extra hardware stage (possible audio loss) out of
the
picture.

 

Thanks!

 

Geoffrey Wolf

AB3LS - Amateur Radio Callsign

University of Pittsburgh '14

[hidden email]

[hidden email]

(412) 450-1310

 

______________________________________________________________
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Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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Please help support this email list: http://www.qsl.net/donate.html
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Re: (phase signals RE: SDR IQ/IF Questions

Pete Smith N4ZR
There is one other consideration with mentioning, and that is that
because the LP-PAN uses your computer's sound card, it is at least
theoretically subject to image problem as a result of amplitude and
phase imbalances between the I and Q channels, where the SDR-IQ passes
those data in digital form.  Cw Skimmer recognizes this issue and
includes automatic amplitude and phase balancing functions in software.

73, Pete N4ZR

The World Contest Station Database, updated daily at www.conteststations.com
The Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com,
spots at telnet.reversebeacon.net, port 7000



On 4/6/2011 4:52 PM, George A. Thornton wrote:

> IQ data is a method for describing the characteristics of a wave.  IQ
> uses amplitude and phase angle to describe the wave, see for example
>
>   http://zone.ni.com/devzone/cda/tut/p/id/3013
>
> The K3 takes an RF signal from an antenna, filters and modulates it.  At
> some point the filtered, modulated signal is made available to an IF out
> port where it can be used conveniently by various testing and measuring
> devices.
>
> A panadapter takes the IF signal and converts it into IQ signals.  These
> IQ signals can then be used to visually represent characteristics of the
> signal on a chart or screen.  The LP-pan converts the I and Q signals to
> audio for input into a computer using a sound card.  The P3 panadapter
> directly charts the IQ data onto the built in screen.
>
> The SDR-IQ is a standalone software designed receiver.  It is designed
> to hook directly into an antenna source and can be used with software to
> directly display data about the signal.  I do not believe it is designed
> to work with modulated IF output from a quality receiver, but I could be
> wrong.
>
> The SDR-IQ can be used as a standalone panadapter through a computer,
> getting its signal direct from the antenna, completely bypassing the
> transceiver altogether.  According to its own manual it does not have
> much filtering and it can get overwhelmed by other RF sources.
>
> The price for the LP-Pan and sound card is less than the price for the
> SDR-IQ.  The P3 costs only a small amount more than the SDR-IQ.
>
> The P3 and LP-Pan were compared in a recent QST article.  According to
> the testers, the two approaches are roughly equal in their ability to
> decode and display weak signals.
>
> The LP-Pan has the advantage of allowing the use of a large computer
> screen for a panadapter. The disadvantage is that it is complex to set
> up, requires use of buggy computers and software with driver
> compatibility issues and has a lot of loose wiring.
>
> The P3 is a plug and play solution that is reliable and easy to use. The
> P3 is more closely integrated with the K3.  IN the future the P3 is
> going to allow direct connection to a computer monitor and keyboard.
>
> Given all the factors, I do not think the SDR-IQ solution is the best
> choice here.
>
>
>
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of Geoffrey Wolf
> Sent: Wednesday, April 06, 2011 10:30 AM
> To: [hidden email]
> Subject: [Elecraft] SDR IQ/IF Questions
>
> Hello fellow SDR enthusiasts,
>
>
>
> I have looked around a little bit and haven't found a very definitive
> answer
> for the questions that I'm having about the way the K3 and external SDR
> equipment works.
>
>
>
> I've been looking into the LP-Pan which converts the IF output from the
> K3
> into (im guessing) audio signals which then are converted into digital
> data
> by a soundcard. The trouble I'm having is understanding what exactly I/Q
> is.
> > From what I understand, I/Q is digital data that software like CW
> Skimmer
> understands.
>
>
>
> Now, I've also been looking at the SDR-IQ which does all of this
> internally
> by taking the IF output from the K3 and converts it directly into
> digital
> data which is then ferried to the computer over USB, forgoing the need
> for
> an extra soundcard.
>
>
>
> Now, I've seen two versions of PowerSDR. I've seen PowerSDR/IF (looks
> more
> developed/supported), and PowerSDR-IQ. What is the difference?
>
>
>
> I suppose the summary question of this email is. can you use PowerSDR/IF
> with an SDR-IQ rather than an LP-Pan? I personally would rather buy an
> SDR-IQ and take that extra hardware stage (possible audio loss) out of
> the
> picture.
>
>
>
> Thanks!
>
>
>
> Geoffrey Wolf
>
> AB3LS - Amateur Radio Callsign
>
> University of Pittsburgh '14
>
> [hidden email]
>
> [hidden email]
>
> (412) 450-1310
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>
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Re: (phase signals RE: SDR IQ/IF Questions

John Ragle
In reply to this post by George Thornton
The URL posted by Mr. Thornton is part of an excellent mid-level
tutorial series, quite worth reading.

I wanted to mention, in this mix, another SDR which seems to be somewhat
unknown in this country; /vide/ http://www.rfsystem.it/shop/... This
receiver "PMSDR" has T/R switching, covers up into the VHF region, and
is physically very small and available in kit form. I had one of the
early models, and was quite pleased with its quality. In its newest
form, it can serve as a stand-alone unit or as a panadapter with, for
example, the K3. I believe there is a US/Canadian dealer.

QST's articles do not demonstrate any particular expertise or breadth of
knowledge in this field.

John Ragle -- W1ZI

=====

On 4/6/2011 4:52 PM, George A. Thornton wrote:

> ...see for example
>
>   http://zone.ni.com/devzone/cda/tut/p/id/3013
>
> The price for the LP-Pan and sound card is less than the price for the
> SDR-IQ.  The P3 costs only a small amount more than the SDR-IQ.
>
> The P3 and LP-Pan were compared in a recent QST article.  According to
> the testers, the two approaches are roughly equal in their ability to
> decode and display weak signals.
>

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(phase signals RE: SDR IQ/IF Questions

Edward R Cole
In reply to this post by AB3LS
Geoff,

I have both the SDR-IQ and LP-Pan (but not the P3).  Essentially, all
are SDR's and convert the RF signal into two signals which are
90-degrees out of phase with each other, thus the I and Q
designations.  Difference is that the SDR-IQ is a stand-alone
receiver covering 500-Hz to 30-MHz and connects directly to a
computer using USB (so the I-Q signals are data streams).  The LP-Pan
is dedicated SDR set on the IF of the K3 (or other radios, if
desired) and produces I-Q audio signals sent to a soundcard for
conversion to data in your computer.  The P3 is a stand-alone
panadaptor with built-in SDR for processing the IF from the K3.

I bought my LP-Pan for about $150 used.  SDR-IQ runs about $500 and
P3 even more.
You can run a SDR-IQ connected to the K3 IF by tuning it to 8.215 MHz
or run it separately.

But for your money (if you already have a K3) the LP-Pan is best and
will do everything the SDR-IQ does (within the restrictions of the K3).
I bought the LP preamps for my LP-Pan as I wanted maximum sensitivity.

I recently figured out how to slave two LP-Pan to a single xtal LO so
they would be phase-locked and do dual-Rx diversity reception.  Info
on my website under "LINRAD".

I only take exception with one paragraph George makes: "The K3 takes
an RF signal from an antenna, filters and modulates it."  The
received signal is not "modulated".  It is filtered, amplified and
converted to the first IF for use by external SDR's.  The roofing
filters do not come into play or the 2nd IF/SDR of the K3,
itself.  There is no modulation or demodulation by the
K3.  Demodulation is done by the DSP sw in the computer.

LP-Pan is a great little Rx to get acquainted with SDR.

73, Ed - KL7UW
------------------------------

Message: 51
Date: Wed, 6 Apr 2011 13:52:53 -0700
From: "George A. Thornton" <[hidden email]>
Subject: [Elecraft] (phase signals RE:  SDR IQ/IF Questions
To: "Geoffrey Wolf" <[hidden email]>,
         <[hidden email]>
Message-ID:
         <[hidden email]>

Content-Type: text/plain;       charset="us-ascii"

IQ data is a method for describing the characteristics of a wave.  IQ
uses amplitude and phase angle to describe the wave, see for example

  http://zone.ni.com/devzone/cda/tut/p/id/3013

The K3 takes an RF signal from an antenna, filters and modulates it.  At
some point the filtered, modulated signal is made available to an IF out
port where it can be used conveniently by various testing and measuring
devices.

A panadapter takes the IF signal and converts it into IQ signals.  These
IQ signals can then be used to visually represent characteristics of the
signal on a chart or screen.  The LP-pan converts the I and Q signals to
audio for input into a computer using a sound card.  The P3 panadapter
directly charts the IQ data onto the built in screen.

The SDR-IQ is a standalone software designed receiver.  It is designed
to hook directly into an antenna source and can be used with software to
directly display data about the signal.  I do not believe it is designed
to work with modulated IF output from a quality receiver, but I could be
wrong.

The SDR-IQ can be used as a standalone panadapter through a computer,
getting its signal direct from the antenna, completely bypassing the
transceiver altogether.  According to its own manual it does not have
much filtering and it can get overwhelmed by other RF sources.

The price for the LP-Pan and sound card is less than the price for the
SDR-IQ.  The P3 costs only a small amount more than the SDR-IQ.

The P3 and LP-Pan were compared in a recent QST article.  According to
the testers, the two approaches are roughly equal in their ability to
decode and display weak signals.

The LP-Pan has the advantage of allowing the use of a large computer
screen for a panadapter. The disadvantage is that it is complex to set
up, requires use of buggy computers and software with driver
compatibility issues and has a lot of loose wiring.

The P3 is a plug and play solution that is reliable and easy to use. The
P3 is more closely integrated with the K3.  IN the future the P3 is
going to allow direct connection to a computer monitor and keyboard.

Given all the factors, I do not think the SDR-IQ solution is the best
choice here.






73, Ed - KL7UW, WD2XSH/45
======================================
BP40IQ   500 KHz - 10-GHz   www.kl7uw.com
EME: 144-1.4kw, 432-100w, 1296-testing*, 3400-winter?
DUBUS Magazine USA Rep [hidden email]
======================================
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Re: (phase signals RE: SDR IQ/IF Questions

Wes Stewart
In reply to this post by George Thornton
Just a couple of extra thoughts.

I use an SDR-IQ as a panadapter on the i-f output of my K3 and it works (*almost) flawlessly.  

(*I have never found anything with a microprocessor in it to work completely flawlessly).

So the SDR-IQ can be used both as a standalone receiver with decent demodulation capability with the supplied SpectraVue software and/or as an excellent panadapter with the same software.  This has a good (i.e simple) GUI and serves the purpose well.

SDR-Radio is another program that supports the SDR-IQ but it is way too complicated and changes sometimes several times a day.  Not ready for prime time in my view. (Flame suit on)

The LP-Pan works well with a decent soundcard, but suffers from the use of PowerSDR software, which is simply awful in my opinion, and lots of cabling.

I have seen a prototype P3 in action, but don't have extensive knowledge of it, other than to note that the screen is too small for my taste and located in the wrong place.  The proposed VGA output will solve the screen size problem, but unless I'm mistaken, precludes the use of the same display for several programs.

My current setup has a laptop usually with a web browser displayed and N1MM (if contesting) or DXBase (if DXing), MMTTY and the panadapter window all on a second monitor.  For my purpose this is the most functional option.

Wes  N7WS

--- On Wed, 4/6/11, George A. Thornton <[hidden email]> wrote:

> IQ data is a method for describing
> the characteristics of a wave.  IQ
> uses amplitude and phase angle to describe the wave, see
> for example
>
>  http://zone.ni.com/devzone/cda/tut/p/id/3013
>
> The K3 takes an RF signal from an antenna, filters and
> modulates it.  At
> some point the filtered, modulated signal is made available
> to an IF out
> port where it can be used conveniently by various testing
> and measuring
> devices.
>
> A panadapter takes the IF signal and converts it into IQ
> signals.  These
> IQ signals can then be used to visually represent
> characteristics of the
> signal on a chart or screen.  The LP-pan converts the
> I and Q signals to
> audio for input into a computer using a sound card. 
> The P3 panadapter
> directly charts the IQ data onto the built in screen.
>
> The SDR-IQ is a standalone software designed
> receiver.  It is designed
> to hook directly into an antenna source and can be used
> with software to
> directly display data about the signal.  I do not
> believe it is designed
> to work with modulated IF output from a quality receiver,
> but I could be
> wrong.
>
> The SDR-IQ can be used as a standalone panadapter through a
> computer,
> getting its signal direct from the antenna, completely
> bypassing the
> transceiver altogether.  According to its own manual
> it does not have
> much filtering and it can get overwhelmed by other RF
> sources. 
>
> The price for the LP-Pan and sound card is less than the
> price for the
> SDR-IQ.  The P3 costs only a small amount more than
> the SDR-IQ.
>
> The P3 and LP-Pan were compared in a recent QST
> article.  According to
> the testers, the two approaches are roughly equal in their
> ability to
> decode and display weak signals. 
>
> The LP-Pan has the advantage of allowing the use of a large
> computer
> screen for a panadapter. The disadvantage is that it is
> complex to set
> up, requires use of buggy computers and software with
> driver
> compatibility issues and has a lot of loose wiring. 
>
> The P3 is a plug and play solution that is reliable and
> easy to use. The
> P3 is more closely integrated with the K3.  IN the
> future the P3 is
> going to allow direct connection to a computer monitor and
> keyboard.
>
> Given all the factors, I do not think the SDR-IQ solution
> is the best
> choice here.
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Re: SDR IQ/IF Questions

N8LP
In reply to this post by AB3LS
  Hi Geoffrey. I just read through your thread (I receive the reflector
in digest mode). I didn't see one of your questions answered, so I will
tackle it...

I'm not aware of any version of PowerSDR which works with SDR-IQ. The
interface has to be a sound card. My favorite version of PowerSDR is the
/IF version by Scott, WU2X. I have tried others like PowerSDR/IQ, but
they are not as well integrated with the K3 or LP-Bridge.

A recent addition, on which I am a contributing developer, is TRX-Pan.
It is much simpler and cleaner looking than PowerSDR/IF and integrates
more tightly with the K3. In fact, more tightly than any other
panadapter for the K3, I believe. You can read about it here,
http://www.telepostinc.com/TRXP.html TRX-Pan does not provide
demodulated audio as PowerSDR does, so it can't be used as a sub-rcvr,
but it does display and track passbands for both VFOs very nicely. It's
more like a P3 with huge screen and mouse control.

I wasn't aware that Quisk now supports Windoze. Leigh might have
mentioned this and I just forgot. I will play with it when I have some
time. Maybe it could be customized to the level that TRX-Pan is in terms
of K3 / LP-Bridge integration.

Before deciding on a PC based solution versus a partial PC based
solution versus a standalone solution, I would download and play with
the programs that would be required for any of these. They are all
available as a free download, although WU2X requests a donation to
support PowerSDR/IF if you decide to go that route. You can set these up
to control the rig and display noise from your sound card. This will
help you decide if the PC approach is right for you.

73,
Larry N8LP



On 4/6/2011 5:11 PM, [hidden email] wrote:

> Date: Wed, 6 Apr 2011 13:29:45 -0400
> From: "Geoffrey Wolf"<[hidden email]>
> Subject: [Elecraft] SDR IQ/IF Questions
> To:<[hidden email]>
> Message-ID:<000f01cbf480$39143d10$ab3cb730$@gmail.com>
> Content-Type: text/plain; charset="us-ascii"
>
> Hello fellow SDR enthusiasts,
>
>
>
> I have looked around a little bit and haven't found a very definitive answer
> for the questions that I'm having about the way the K3 and external SDR
> equipment works.
>
>
>
> I've been looking into the LP-Pan which converts the IF output from the K3
> into (im guessing) audio signals which then are converted into digital data
> by a soundcard. The trouble I'm having is understanding what exactly I/Q is.
> > From what I understand, I/Q is digital data that software like CW Skimmer
> understands.
>
>
>
> Now, I've also been looking at the SDR-IQ which does all of this internally
> by taking the IF output from the K3 and converts it directly into digital
> data which is then ferried to the computer over USB, forgoing the need for
> an extra soundcard.
>
>
>
> Now, I've seen two versions of PowerSDR. I've seen PowerSDR/IF (looks more
> developed/supported), and PowerSDR-IQ. What is the difference?
>
>
>
> I suppose the summary question of this email is. can you use PowerSDR/IF
> with an SDR-IQ rather than an LP-Pan? I personally would rather buy an
> SDR-IQ and take that extra hardware stage (possible audio loss) out of the
> picture.
>
>
>
> Thanks!
>
>
>
> Geoffrey Wolf
>
> AB3LS - Amateur Radio Callsign
>
> University of Pittsburgh '14
>
> [hidden email]
>
> [hidden email]
>
> (412) 450-1310

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Re: SDR IQ/IF Questions

Joe Subich, W4TV-4

Larry,

 > A recent addition, on which I am a contributing developer, is TRX-Pan.
 > It is much simpler and cleaner looking than PowerSDR/IF and integrates
 > more tightly with the K3.

Does TRX-Pan support SDR-IQ or is it limited to soundcard based
devices?

73,

    ... Joe, W4TV


On 4/6/2011 10:09 PM, Larry Phipps wrote:

>    Hi Geoffrey. I just read through your thread (I receive the reflector
> in digest mode). I didn't see one of your questions answered, so I will
> tackle it...
>
> I'm not aware of any version of PowerSDR which works with SDR-IQ. The
> interface has to be a sound card. My favorite version of PowerSDR is the
> /IF version by Scott, WU2X. I have tried others like PowerSDR/IQ, but
> they are not as well integrated with the K3 or LP-Bridge.
>
> A recent addition, on which I am a contributing developer, is TRX-Pan.
> It is much simpler and cleaner looking than PowerSDR/IF and integrates
> more tightly with the K3. In fact, more tightly than any other
> panadapter for the K3, I believe. You can read about it here,
> http://www.telepostinc.com/TRXP.html TRX-Pan does not provide
> demodulated audio as PowerSDR does, so it can't be used as a sub-rcvr,
> but it does display and track passbands for both VFOs very nicely. It's
> more like a P3 with huge screen and mouse control.
>
> I wasn't aware that Quisk now supports Windoze. Leigh might have
> mentioned this and I just forgot. I will play with it when I have some
> time. Maybe it could be customized to the level that TRX-Pan is in terms
> of K3 / LP-Bridge integration.
>
> Before deciding on a PC based solution versus a partial PC based
> solution versus a standalone solution, I would download and play with
> the programs that would be required for any of these. They are all
> available as a free download, although WU2X requests a donation to
> support PowerSDR/IF if you decide to go that route. You can set these up
> to control the rig and display noise from your sound card. This will
> help you decide if the PC approach is right for you.
>
> 73,
> Larry N8LP
>
>
>
> On 4/6/2011 5:11 PM, [hidden email] wrote:
>> Date: Wed, 6 Apr 2011 13:29:45 -0400
>> From: "Geoffrey Wolf"<[hidden email]>
>> Subject: [Elecraft] SDR IQ/IF Questions
>> To:<[hidden email]>
>> Message-ID:<000f01cbf480$39143d10$ab3cb730$@gmail.com>
>> Content-Type: text/plain; charset="us-ascii"
>>
>> Hello fellow SDR enthusiasts,
>>
>>
>>
>> I have looked around a little bit and haven't found a very definitive answer
>> for the questions that I'm having about the way the K3 and external SDR
>> equipment works.
>>
>>
>>
>> I've been looking into the LP-Pan which converts the IF output from the K3
>> into (im guessing) audio signals which then are converted into digital data
>> by a soundcard. The trouble I'm having is understanding what exactly I/Q is.
>>>  From what I understand, I/Q is digital data that software like CW Skimmer
>> understands.
>>
>>
>>
>> Now, I've also been looking at the SDR-IQ which does all of this internally
>> by taking the IF output from the K3 and converts it directly into digital
>> data which is then ferried to the computer over USB, forgoing the need for
>> an extra soundcard.
>>
>>
>>
>> Now, I've seen two versions of PowerSDR. I've seen PowerSDR/IF (looks more
>> developed/supported), and PowerSDR-IQ. What is the difference?
>>
>>
>>
>> I suppose the summary question of this email is. can you use PowerSDR/IF
>> with an SDR-IQ rather than an LP-Pan? I personally would rather buy an
>> SDR-IQ and take that extra hardware stage (possible audio loss) out of the
>> picture.
>>
>>
>>
>> Thanks!
>>
>>
>>
>> Geoffrey Wolf
>>
>> AB3LS - Amateur Radio Callsign
>>
>> University of Pittsburgh '14
>>
>> [hidden email]
>>
>> [hidden email]
>>
>> (412) 450-1310
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
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Re: SDR IQ/IF Questions

N8LP
  Sound card only.

Larry N8LP



On 4/6/2011 11:14 PM, Joe Subich, W4TV wrote:

>
> Larry,
>
> > A recent addition, on which I am a contributing developer, is TRX-Pan.
> > It is much simpler and cleaner looking than PowerSDR/IF and integrates
> > more tightly with the K3.
>
> Does TRX-Pan support SDR-IQ or is it limited to soundcard based
> devices?
>
> 73,
>
>    ... Joe, W4TV
>
>
> On 4/6/2011 10:09 PM, Larry Phipps wrote:
>>    Hi Geoffrey. I just read through your thread (I receive the reflector
>> in digest mode). I didn't see one of your questions answered, so I will
>> tackle it...
>>
>> I'm not aware of any version of PowerSDR which works with SDR-IQ. The
>> interface has to be a sound card. My favorite version of PowerSDR is the
>> /IF version by Scott, WU2X. I have tried others like PowerSDR/IQ, but
>> they are not as well integrated with the K3 or LP-Bridge.
>>
>> A recent addition, on which I am a contributing developer, is TRX-Pan.
>> It is much simpler and cleaner looking than PowerSDR/IF and integrates
>> more tightly with the K3. In fact, more tightly than any other
>> panadapter for the K3, I believe. You can read about it here,
>> http://www.telepostinc.com/TRXP.html TRX-Pan does not provide
>> demodulated audio as PowerSDR does, so it can't be used as a sub-rcvr,
>> but it does display and track passbands for both VFOs very nicely. It's
>> more like a P3 with huge screen and mouse control.
>>
>> I wasn't aware that Quisk now supports Windoze. Leigh might have
>> mentioned this and I just forgot. I will play with it when I have some
>> time. Maybe it could be customized to the level that TRX-Pan is in terms
>> of K3 / LP-Bridge integration.
>>
>> Before deciding on a PC based solution versus a partial PC based
>> solution versus a standalone solution, I would download and play with
>> the programs that would be required for any of these. They are all
>> available as a free download, although WU2X requests a donation to
>> support PowerSDR/IF if you decide to go that route. You can set these up
>> to control the rig and display noise from your sound card. This will
>> help you decide if the PC approach is right for you.
>>
>> 73,
>> Larry N8LP
>>
>>
>>
>> On 4/6/2011 5:11 PM, [hidden email] wrote:
>>> Date: Wed, 6 Apr 2011 13:29:45 -0400
>>> From: "Geoffrey Wolf"<[hidden email]>
>>> Subject: [Elecraft] SDR IQ/IF Questions
>>> To:<[hidden email]>
>>> Message-ID:<000f01cbf480$39143d10$ab3cb730$@gmail.com>
>>> Content-Type: text/plain;    charset="us-ascii"
>>>
>>> Hello fellow SDR enthusiasts,
>>>
>>>
>>>
>>> I have looked around a little bit and haven't found a very
>>> definitive answer
>>> for the questions that I'm having about the way the K3 and external SDR
>>> equipment works.
>>>
>>>
>>>
>>> I've been looking into the LP-Pan which converts the IF output from
>>> the K3
>>> into (im guessing) audio signals which then are converted into
>>> digital data
>>> by a soundcard. The trouble I'm having is understanding what exactly
>>> I/Q is.
>>>>  From what I understand, I/Q is digital data that software like CW
>>>> Skimmer
>>> understands.
>>>
>>>
>>>
>>> Now, I've also been looking at the SDR-IQ which does all of this
>>> internally
>>> by taking the IF output from the K3 and converts it directly into
>>> digital
>>> data which is then ferried to the computer over USB, forgoing the
>>> need for
>>> an extra soundcard.
>>>
>>>
>>>
>>> Now, I've seen two versions of PowerSDR. I've seen PowerSDR/IF
>>> (looks more
>>> developed/supported), and PowerSDR-IQ. What is the difference?
>>>
>>>
>>>
>>> I suppose the summary question of this email is. can you use
>>> PowerSDR/IF
>>> with an SDR-IQ rather than an LP-Pan? I personally would rather buy an
>>> SDR-IQ and take that extra hardware stage (possible audio loss) out
>>> of the
>>> picture.
>>>
>>>
>>>
>>> Thanks!
>>>
>>>
>>>
>>> Geoffrey Wolf
>>>
>>> AB3LS - Amateur Radio Callsign
>>>
>>> University of Pittsburgh '14
>>>
>>> [hidden email]
>>>
>>> [hidden email]
>>>
>>> (412) 450-1310
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
>

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Re: SDR IQ/IF Questions

Torsten Clay
Another new (free) software package under development combining an I/Q SDR panadapter and a contest logging program. Supports linux and windows:

http://code.google.com/p/so2sdr/

features of the SDR panadapter with SO2SDR:

-supports dual panadapter displays (for two radio contesting)
-auto I/Q balancing
-peak detection of signals
-ability to mark signals on the panadapter (use to mark dupes in CW contests)
-can be used to find open (unused) frequencies on a band
-special support for Elecraft radios: it automatically inverts the display for the K2 when on the upper bands, for the K3 it reads the correct IF offset for the filter in use

I can't guarantee it is completely free of bugs, but I use it for my own operating :)

Tor
N4OGW
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Re: (phase signals RE: SDR IQ/IF Questions

Alexander Sack
In reply to this post by George Thornton
On Wed, Apr 6, 2011 at 4:52 PM, George A. Thornton
<[hidden email]> wrote:
> The P3 is a plug and play solution that is reliable and easy to use. The
> P3 is more closely integrated with the K3.  IN the future the P3 is
> going to allow direct connection to a computer monitor and keyboard.


Was going to ask this in a separate thread, but when EXACTLY is P3
video output on the roadmap?  Its the only thing preventing me from
pulling the trigger.  Also if I buy one now, can I get the output
update later (is this purely a firmware issue?).

73's,

-aps (KC2ZSX)
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