[hpsdr] ozy/janus as soundcard for digital modes

[Sid Boyce]

Preaching to the converted. I misconstrued that you didn't know about 
the the Softrock IF.
73 ... Sid.

On 03/11/11 14:18, Stephen West-Fisher wrote:
> ***** High Performance Software Defined Radio Discussion List *****
>
> Excellent job with small device, that does explain what I am seeing - and
> why it is different from when I hook up the Softrock I have. So on to
> figuring out why the Janus analogue in/out doesn't appear to do anything....
>
> --
> Stephen West-Fisher
> N4IK
>
>
> -----Original Message-----
> From: Jeremy McDermond [mailto:mcdermj at xenotropic.com]
> Sent: Thursday, November 03, 2011 9:59 AM
> To: Stephen West-Fisher
> Subject: Re: [hpsdr] ozy/janus as soundcard for digital modes
>
> We'll see how this goes typing a missive in my iPhone, but I don't have full
> Internet connectivity.
>
> I think part of your confusion is that the I and Q signals have to be
> digital. What the Softrock actually does is use analog mixing to create two
> analog signals, one representing I (in phase) and one Q (90 degrees out of
> phase). Your sound cards right and left channels then are used to capture
> each of the I and Q. Janus was designed similarly to sample I and Q from an
> SDR 1000.
>
> You are probably seeing output on your setup because PowerSDR is getting the
> audio on the I channel of Janus. You can indeed do a lot with just the real
> portion of the signal because it's already been demodulated by your analog
> transceiver. You might be able to do similarly on transmit, but it will
> probably be very difficult to suppress the Q side of the signal out of PSDR.
> You are seeing weird input on the waterfall, etc. because PSDR is expecting
> both components of the signal but is only seeing the real demodulated part.
> The complex FFTs won't work right without both components.
>
> --Jeremy (NH6Z)
>
> Sent from my iPhone
>
> On Nov 3, 2011, at 6:27 AM, "Stephen West-Fisher"
> <steve at coastaldatasystems.com>  wrote:
>
>> ***** High Performance Software Defined Radio Discussion List *****
>>
>> No need to shout, and actually I thought I was quite clear in my response
> to
>> Phil that the TS-480 only has analog audio out and in. My understanding of
>> the HPSDR project is that it is for experimentation and learning, so I'm
>> doing both.
>>
>> So you are saying that I/Q data can go into an analog audio input but an
>> analog audio output cannot go into an I/Q data port? Since I was able to
>> decode PSK-32 doing just that I'm not sure I completely agree. I do know
> the
>> panadapter display looks quite odd, and I have not done any comparison of
>> how well it works compared to just hooking up to a standard soundcard.
>> Performance may be quite marginal, but I did get a positive response.
>>
>> So then, since Janus was designed as an A/D and D/A adapter (with the TI
>> TLV320AIC23B) and has non I/Q inputs and outputs so it appears to me the
>> hardware should be able to handle the appropriate audio to digital
>> conversion. If the hardware is capable, then the software would be the
>> problem and Phil's response to me leads to that conclusion (windows
> driver).
>> If there is a problem with this statement, please let me know where I'm
>> going wrong.
>>
>> At this point the clue I am looking for is where the problem lies, Janus
>> firmware or PowerSDR code?
>>
>> --
>> Stephen West-Fisher
>> N4IK
>>
>>
>> -----Original Message-----
>> From: hpsdr-bounces at lists.openhpsdr.org
>> [mailto:hpsdr-bounces at lists.openhpsdr.org] On Behalf Of george byrkit
>> Sent: Thursday, November 03, 2011 8:14 AM
>> To: hpsdr at lists.openhpsdr.org
>> Subject: Re: [hpsdr] ozy/janus as soundcard for digital modes
>>
>> ***** High Performance Software Defined Radio Discussion List *****
>>
>> Dear Stephen,
>> The 'normal sound card' is used to receive I/Q data from the SDR-1000,
> which
>> is then processed by PowerSDR.
>>
>> Janus has better resolution and more stable timing than most sound cards,
>> and the USB conntection thru Ozy has much less latency (delay) than a
> normal
>> sound card would.
>>
>> So UNLESS YOUR TS480 OUTPUTS I/Q data (which you have not yet confirmed or
>> denied), PowerSDR WILL NOT WORK WITH IT.
>>
>> 73,
>> George K9TRV
>>
>> _______________________________________________
>> HPSDR Discussion List
>> To post msg: hpsdr at openhpsdr.org
>> Subscription help:
>> http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
>> HPSDR web page: http://openhpsdr.org
>> Archives: http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/
>>
>> _______________________________________________
>> HPSDR Discussion List
>> To post msg: hpsdr at openhpsdr.org
>> Subscription help:
> http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
>> HPSDR web page: http://openhpsdr.org
>> Archives: http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/
>>
> _______________________________________________
> HPSDR Discussion List
> To post msg: hpsdr at openhpsdr.org
> Subscription help: http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
> HPSDR web page: http://openhpsdr.org
> Archives: http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/
>


-- 
Sid Boyce ... Hamradio License G3VBV, Licensed Private Pilot,
Emeritus IBM/Amdahl Mainframes and Sun/Fujitsu Servers Tech Support
Senior Staff Specialist, Cricket Coach
Microsoft Windows Free Zone - Linux used for all Computing Tasks


 1320330231.0