Sound Card I/Q Sample Delay - A future feature ?


HBOttiki@...
 

Hi,

as some of you might be aware, some sound cards exihibit the annoying problem of a sample delay on one channel and the digitized data is therefore delivered to SDR software sooner or later than those processed by the other channel which causes big trouble in I/Q mode applications.

Most commom SDR programs such as Winrad, Rocky or PowerSDR have the possibility to delay the sound card sample processing of Left or Right channel by one sample (Winrad even most flexible allowing 1-4 samples delay, but perhaps this is total overkill).

For example my Sounblaster Live24 exhibits such a sample delay problem.
I would like to use it with my Softrock V9 in SDR-Radio, but currently can't make use of it, because of the sample delay doesn't allow proper image rejection.

I wonder if this problem is known and currently in the "To Do" list for SDR-Radio?

Best 73 de Oscar, DJ0MY


--
GRATIS für alle GMX-Mitglieder: Die maxdome Movie-FLAT!
Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome01


Bruce Tanner
 

Oscar, not to pump the competition, but, both "Rock" and " PSDR" should allow you to make compensations for latency in those cases. You might give them a whirl if you have not done so.

bet
-----------

On 7/30/2010 6:26 PM, HBOttiki@... wrote:

 


Hi,

as some of you might be aware, some sound cards exihibit the annoying problem of a sample delay on one channel and the digitized data is therefore delivered to SDR software sooner or later than those processed by the other channel which causes big trouble in I/Q mode applications.

Most commom SDR programs such as Winrad, Rocky or PowerSDR have the possibility to delay the sound card sample processing of Left or Right channel by one sample (Winrad even most flexible allowing 1-4 samples delay, but perhaps this is total overkill).

For example my Sounblaster Live24 exhibits such a sample delay problem.
I would like to use it with my Softrock V9 in SDR-Radio, but currently can't make use of it, because of the sample delay doesn't allow proper image rejection.

I wonder if this problem is known and currently in the "To Do" list for SDR-Radio?

Best 73 de Oscar, DJ0MY

--
GRATIS für alle GMX-Mitglieder: Die maxdome Movie-FLAT!
Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome01


Bruce Tanner
 

Sorry! 'Rock" should be 'Rocky"!

On 7/30/2010 8:11 PM, Bruce Tanner wrote:

 

Oscar, not to pump the competition, but, both "Rock" and " PSDR" should allow you to make compensations for latency in those cases. You might give them a whirl if you have not done so.

bet
-----------

On 7/30/2010 6:26 PM, HBOttiki@gmx.de wrote:

 


Hi,

as some of you might be aware, some sound cards exihibit the annoying problem of a sample delay on one channel and the digitized data is therefore delivered to SDR software sooner or later than those processed by the other channel which causes big trouble in I/Q mode applications.

Most commom SDR programs such as Winrad, Rocky or PowerSDR have the possibility to delay the sound card sample processing of Left or Right channel by one sample (Winrad even most flexible allowing 1-4 samples delay, but perhaps this is total overkill).

For example my Sounblaster Live24 exhibits such a sample delay problem.
I would like to use it with my Softrock V9 in SDR-Radio, but currently can't make use of it, because of the sample delay doesn't allow proper image rejection.

I wonder if this problem is known and currently in the "To Do" list for SDR-Radio?

Best 73 de Oscar, DJ0MY

--
GRATIS für alle GMX-Mitglieder: Die maxdome Movie-FLAT!
Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome01


Bruce Tanner
 

Oscar, I feel a little nutty! I re-read you comments and now realize that you have done the tasks with Rocky and PSDR. I see that you are asking Simon for such a feature in his software. I second the request and apologize for the improper use of the bandwidth! :)

bet

On 7/30/2010 8:31 PM, Bruce Tanner wrote:

 

Sorry! 'Rock" should be 'Rocky"!

On 7/30/2010 8:11 PM, Bruce Tanner wrote:

 

Oscar, not to pump the competition, but, both "Rock" and " PSDR" should allow you to make compensations for latency in those cases. You might give them a whirl if you have not done so.

bet
-----------

On 7/30/2010 6:26 PM, HBOttiki@gmx.de wrote:

 


Hi,

as some of you might be aware, some sound cards exihibit the annoying problem of a sample delay on one channel and the digitized data is therefore delivered to SDR software sooner or later than those processed by the other channel which causes big trouble in I/Q mode applications.

Most commom SDR programs such as Winrad, Rocky or PowerSDR have the possibility to delay the sound card sample processing of Left or Right channel by one sample (Winrad even most flexible allowing 1-4 samples delay, but perhaps this is total overkill).

For example my Sounblaster Live24 exhibits such a sample delay problem.
I would like to use it with my Softrock V9 in SDR-Radio, but currently can't make use of it, because of the sample delay doesn't allow proper image rejection.

I wonder if this problem is known and currently in the "To Do" list for SDR-Radio?

Best 73 de Oscar, DJ0MY

--
GRATIS für alle GMX-Mitglieder: Die maxdome Movie-FLAT!
Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome01


Simon HB9DRV <simon@...>
 

Hi,

 

Sure - I'll add this.

 

Simon Brown, HB9DRV

http://sdr-radio.com

 

From: sdr-radio-com@... [mailto:sdr-radio-com@...] On Behalf Of HBOttiki@...
Sent: 31 July 2010 00:26
To: sdr-radio-com@...
Subject: [sdr-radio-com] Sound Card I/Q Sample Delay - A future feature ?

 

 


Hi,

as some of you might be aware, some sound cards exihibit the annoying problem of a sample delay on one channel and the digitized data is therefore delivered to SDR software sooner or later than those processed by the other channel which causes big trouble in I/Q mode applications.

Most commom SDR programs such as Winrad, Rocky or PowerSDR have the possibility to delay the sound card sample processing of Left or Right channel by one sample (Winrad even most flexible allowing 1-4 samples delay, but perhaps this is total overkill).

For example my Sounblaster Live24 exhibits such a sample delay problem.
I would like to use it with my Softrock V9 in SDR-Radio, but currently can't make use of it, because of the sample delay doesn't allow proper image rejection.

I wonder if this problem is known and currently in the "To Do" list for SDR-Radio?

Best 73 de Oscar, DJ0MY

--
GRATIS für alle GMX-Mitglieder: Die maxdome Movie-FLAT!
Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome01