Re: [Discuss-gnuradio] external clock

[Marcus Leech]

Bdale Garbee wrote:

> Meanwhile, I poked Matt for an updated delivery estimate on the USRP L
> and S band daughter cards the other day but haven't heard back from him
> yet.  Does anyone else (Eric?) know enough about the design of those to
> share the up/down conversion approach?  Is there another oscillator to
> tame, a PLL driven by a USRP reference clock, or what?  
>
> There's only two months until the first half of the ARRL EME contest,
> which I'd love to be on the air for on 1296...
>
> Bdale
>  
Are you talking about the DBS_RX, or something else?

The DBS_RX uses the USRP refclk, divided down to 4Mhz or so, which
 feeds a PLL-based quadrature direct-conversion receiver, covering
 800Mhz or so to about 2Ghz or so.

The phase noise on the DBS_RX isn't spectacular, because the chip (MAX2118)
 is designed for wideband DBS satellite TV reception.

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