Re: LimeSDR USB parameter help

[Amr Bekhit]

Hi Barry,

I haven't tried it myself, but my understanding is that gr-osmosdr
accesses the LimeSDR via Soapy and so I would have thought that it
doesn't matter what version of GR is running at that point, as long as
the LimeSDR drivers and Soapy are installed. The incompatibility that
the LimeSDR has with GR3.8 is regarding the gr-limesdr blocks, if I'm
not mistaken.

On Mon, 27 Jan 2020 at 01:13, Barry Duggan <address@hidden> wrote:
>
> Hi Amr,
>
> Do you, or anyone else reading this know if gr-osmosdr supports the
> LimeSDR USB in GR 3.8?
>
> Thanks!
> ---
> Barry Duggan KV4FV
>
>
> On 2020-01-24 17:00, Amr Bekhit wrote:
> >> * should it work for GR 3.8?
> >> Right now the Frequency sink just shows random noise.
> > I have worked with the LimeSDR on 3.7, but not on 3.8. According to
> > github, work is still in progress to port LimeSuite to 3.8
> > (https://github.com/myriadrf/gr-limesdr/issues/44)
> >
> >> On the "Properties: LimeSDR Source (RX)" screen:
> >>
> >> Channel A Properties:
> >>    NCO frequency
> > The NCO is used a secondary digital mixer to allow you to tune down to
> > below the 30Mhz limit on the LMS7000. Set it to 0 to allow the driver
> > to automatically calculate it for you.
> >
> >>    Calibration bandwidth
> > This should be set to at least the sampling rate. It sets the
> > bandwidth across which the LimeSDR calibrates out the LO frequency
> > bleeding into the received signal, if I'm not mistaken.
> >
> >>    LNA path
> > This sets the RF input port that is connected to the LMS7000 chip. The
> > LimeSDR has 3 RF inputs per input channel: Low, High and Wideband.
> >
> >>    Analog filter bandwidth
> > This is a programmable analogue filter on the RF input. Like the
> > calibration bandwidth, you can set this to 0 to let the driver
> > calculate it for you.
> >
> >>    Digital filter bandwidth
> > This is a digital filter present after the NCO digital mixer. Again,
> > set to 0.
> >
> >>    Gain (dB)
> > RF input gain - goes from 0-60dB. Probably start with something like
> > 30dB and work from there.
> >
> >>
> >> * is the output signal centered at the RF frequency, or is there an
> >> offset?
> > The output signal should be centred around the RF frequency.
> >
> >>
> >> on the board there are RX1_L, RX_H, RX_W, RX2_L, RX2_H, RX2_W
> >> connectors
> >> INFO: device_handler::set_antenna(): CH0 antenna set [RX]: LNAL.
> >> * which connector corresponds to LNAL? Is it RX1_L?
> >
> > If this is the Channel A tab, then LNAL refers to RX1_L. If it's the
> > Channel B tab then LNAL refers to RX2_L.