[hpsdr] Frequency tuning with Mercury/PowerSDR2025

[Bill Tracey]

Spur reduction is disabled intentionally  - for Mercury it does not 
makes sense since all of the tuning can be done by adjusting the 
Mercury digital NCO in the FPGA to tune.    The cordic is deep enough 
that spur production does not seem to be a problem anymore, and the 
SR points from PowerSDR would not make sense for Mercury since 
PowerSDR calculates  those points  based on a specific DDS - they'd 
not match any spurs in the Mercury Digital NCO.

Can you tell me the date show in the title bar -- the SVN string is 
pretty much useless because it's based on whatever .svn files you 
have running around your local machine, not the svn level at the time 
the code was built.

Regards,

Bill (kdtfd)

At 08:54 PM 12/27/2008, David Woodhead wrote:
>***** High Performance Software Defined Radio Discussion List *****
>
>
>Hi Bob,
>
>Sounds logical but the "spur reduction" feature is grayed out.
>
>David.
>
>-----Original Message-----
>From: Bob McGwier [mailto:rwmcgwier at gmail.com]
>Sent: Sat 12/27/2008 6:25 PM
>To: David Woodhead; hpsdr at lists.hpsdr.org
>Subject: RE: [hpsdr] Frequency tuning with Mercury/PowerSDR2025
>
>I suspect you need to go into the setup on PowerSDR and check the box that
>says "spur reduction".  This really engages the software tuning which is
>what is needed.
>
>Bob
>
>
>ARRL SDR Working Group Chair
>Member: ARRL, AMSAT, AMSAT-DL, TAPR, Packrats,
>NJQRP, QRP ARCI, QCWA, FRC.
>"And yes I said, yes I will Yes", Molly Bloom
>
>-----Original Message-----
>From: hpsdr-bounces at lists.hpsdr.org [mailto:hpsdr-bounces at lists.hpsdr.org]
>On Behalf Of David Woodhead
>Sent: Saturday, December 27, 2008 9:17 PM
>To: hpsdr at lists.hpsdr.org
>Subject: [hpsdr] Frequency tuning with Mercury/PowerSDR2025
>
>***** High Performance Software Defined Radio Discussion List *****
>
>I'm using Mercury with Phil's V2 code and SVN2025. Noticing that the
>frequency tuning is acting strange....
>
>With a CW input at 7MHz and tuning the receiver in 1hz steps the frequency
>only changes at the following transistions
>7.000,041/042
>7.000,100/101
>7.000,158/159
>7.000,217/218
>
>Looks like the min tuning step is ~ 60Hz
>
>Seems to vary with mode. Above was CWL.
>
>David.
>KM5TZ



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