[Discuss-gnuradio] Re: "Open-Hardware"

[Patrick Strasser]

schrieb Marcus D. Leech am 2011-01-12 02:40:

> Well, I *personally* don't care very much about random-disk-noise, errr,
> I mean Windows,
>   but I'm sure others do :-)

There is a lot of people outside the Linux world, especially in the
non-academic hobbyist corner. These people seem to me to try to work
with least possible changes, that is install no new OS, install no
additional tricky exotic drivers, and at most plug in some USB device.
That's perfectly ok for me. If these people should be serverd as well
you unfortunately _have_ to to think about Windows, as hard and painful
as it may seem.

>> I read the UAC1 specs a year ago and thought "Great, you can advertise
>> up to 4MSPS on USB Audio!", but it turned out that it was specified for
>> USB 1.1, which just cannot handle the data rates. :-( Then I found the
>> SDR Widget, and they really get everything out of the Windows UAC1
>> driver.
>>
>>
> I thought you couldn't do more than 48Ksps with UAC1, no way no how.

You can trick Windows to do 192Ksps via UAC1, I think. No sure if its 16
or 24 bit.

>   Perhaps I should read that spec again, but it seems that UAC2 is the
>   way forward, with 384Ksps audiophile DACs using UAC2 already becoming
>   available.

I can think of a way how the SDR Widget people do it: Different
firmwares for UAC1 and UAC2. With a third for a more generic interface,
this could be compatible and fun at the same time.

> An interesting device is the AD6655, which is an integrated ADC and
>   signal processing chain (complex DDC, and one or more CIC decimators
>   and FIR filters). 

Now that is not exactly the cheap one, but with its 150MSPS it would be
quite a frequency range with low additional effort.

What would be the goal for such a device? Which bandwidth are of
interest, which dynamic ranges? Which frequency ranges? Extra frontends?
IF from other transceivers or transverters? What would you do with it?

Oh, I forgot one interesting device:
  http//:www.websdr.org/
Seems the hardware info is not linked any more, but its a DDS board with
Ethernet interface. Very application specific, but all soldered by hand.

Regards

Patrick
-- 
Engineers motto: cheap, good, fast: choose any two
Patrick Strasser <patrick dot strasser at student dot tugraz dot at>
Student of Telemati_cs_, Techn. University Graz, Austria