Re: [Discuss-gnuradio] changing the vctcxo

[Matt Ettus]

Roshan Baliga wrote:
> Hans Glitsch wrote:
> > I just found this one on Digikey: 
> > http://www.abracon.com/Oscillators/ASVTX11.pdf
> >
> > I'm not an experienced hardware guy, but it looks like it would work 
> > in the usrp.  Please tell me if I'm wrong.
>
> I believe the USRP needs a 3 Vpp clock in, and this TCXO only outputs 
> 0.8 Vpp. Plus, it's a clipped sine. So you may want to throw it 
> through a squarer that will bump it up to 0 -> 3V before putting it 
> into J2001. Is this right Matt?

The rev 4 and newer USRPs have a clock generator chip that is spec'ed to 
take a signal as low as 150 mV p-p.  However in my testing I found I 
needed a voltage as high as 8 or 9dBm.  8dBm is about .8V, so that 
should still work.

Matt