[time-nuts] Sound cards

[John Ackermann N8UR]

Rex said the following on 01/09/2009 06:37 AM:

> Maybe I lost track and missed something, but I don't think I ever saw 
> more on the subject of specific high-end sound cards that might be 
> useful for nutty measurements.
> 
> I'd be interested to hear what any of the group has to share about 
> relative merits of current sound cards that can be interfaced for 
> measurements like what was being discussed in that earlier thread. (And 
> some before and since.)
> 
>  From my own point of view, I'd most like to hear about any that are 
> external -- connected by USB or 1394, rather than an internal card. This 
> makes it more portable and easier to move between different PC's.

[Shameless Plug]

One very interesting possibility is the HPSDR (High Performance Software 
Defined Radio) boards called Ozy and Janus.  Together with a passive 
backplane called Atlas, they provide an extremely high performance 
ADC/DAC that supports sampling to 192k and output via USB.  The system 
was designed for use as the interface between a PC and an SDR and 
special attention was paid to low noise and flat frequency response.  I 
am not certain, but I *think* that the inputs are DC coupled.

The two boards, assembled and tested, run about $320, with a discount 
for TAPR members.  The backplane is a fairly simple kit (lots of 
connector pins to solder, but not much complexity) that sells for $28, 
also with a discount for TAPR members.  Bare boards, but not kits, for 
Ozy and Janus are also available for the adventurous.

I'm not aware of anyone using this system for T&F work, but it has some 
interesting possibilities.

[/Shameless Plug]

John