[hpsdr] Metis works! - but, a question

[Warren C. Pratt]

Bill,

Thanks for the further info.  The compander was ON.  Over the next couple
days I'll run tests with Ozy/Metis on the same version of PowerSDR versus my
current Ozy version and I'll try to get more quantitative results driving
with an audio generator.

Thanks again,

Warren  NR0V

-----Original Message-----
From: Bill Tracey [mailto:bill at ewjt.com] 
Sent: Thursday, February 17, 2011 9:05 PM
To: warren at wpratt.com; hpsdr at openhpsdr.org
Subject: Re: [hpsdr] Metis works! - but, a question

Do you see the same issue running Ozy with the 
same version of PowerSDR  you're running with 
Metis?  The change to avoid I/Q clipping is 
independent of Ozy/Metis usage and would only be 
in the signal path if your running with the Compander on.

Regards,

Bill (kd5tfd)

At 07:20 PM 2/17/2011, Warren C. Pratt wrote:
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>First, thanks to both designers and 
>manufacturers for Metis!  I had no problem at 
>all installing H/W and S/W (PowerSDR 1.19.3.3) - 
>works great.  CPU utilization is down a few percent as well.
>
>However, running PowerSDR, I note that the audio 
>settings are different for Metis than with the 
>older version I was using with Ozy and, more 
>importantly, it appears that when I adjust the 
>Mic Gain to achieve similar peak transmit 
>levels, I've lost about 10db of signal-to-noise 
>ratio on transmit.  With the equalizer on, 
>boosting highs, I see about 50dB S/N on Ozy and 
>about 40dB on Metis.  I can unplug the mic and 
>it makes no difference in the base level.
>
>Two questions:  (1) Can anyone else verify this 
>result or is it unique to me?  (2) Could this 
>relate to PowerSDR changes to resolve the I/Q 
>wrap-around problem that was mentioned on TeamSpeak?
>
>Thanks,
>
>Warren  NR0V
>
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