Re: [Discuss-gnuradio] Sampling rate of USRP board

[Hans Glitsch]

Hi,

You can use decimation and a rational_resampler block.

If you really need to change the clock read this: 
http://www.comsec.com/wiki?USRPClockingNotes
It explains how to use an external clock source with the usrp.  I was able 
to use a 38.4MHz clock with the usrp from a signal generator.  It seemed to 
work fine, so I bought a new 38.4MHz tcvcxo and installed it on the board.

I hope that helps you,
Hans

----- Original Message ----- 
From: "eenrti" <address@hidden>
Cc: "Matt Ettus" <address@hidden>; "Eric Blossom" <address@hidden>; "gnuradio 
mailing list" <address@hidden>
Sent: Monday, March 26, 2007 10:00 AM
Subject: [Discuss-gnuradio] Sampling rate of USRP board


> Hello,
> I have recently purchased the USRP board and the RX daughterboard, and I 
> have started working on them.
> One major factor that I need to change is the sampling rate frequency of 
> the ADCs on USRP, I know the USRP clock is at 64MSPS and I need to reduce 
> it to at least half of it.
> My question is two fold, should I decimate the digitization, or is there 
> any other way of doing that? How difficult would be to change the clock?
> And can someone confirm that the USRP can accept an external clock? If yes 
> do I need to have some hardware adjustments?
>
> Please excuse me if I repeat an older thread, it would be nice to guide me 
> there. I think that it might could be a good idea to have some kind of 
> forum, with different parts dedicated to USRP.
>
> Regards
>
> Rigas Ioannides
>
>
>
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