[ntp:questions] Re: Where to obtain audioio.h

Tim Shoppa shoppa at trailing-edge.com
Mon Sep 8 20:50:05 UTC 2003


"David L. Mills" <mills at udel.edu> wrote in message news:<3F5BC91D.2CE1F89 at udel.edu>...
> Ouch, that must hurt a lot. Far better to hack ./libntp/audio.c and
> leave the refclock_wwv.c alone.

Whoops, I mis-stated the drivers from www.wraith.sf.ca.us/ntp that
I actually applied - only the libntp/audio.c was necessary for Linux
AFAIK.  I had to muck about with some configure options too (I really
should've made a note.)  

There is a patch for refclock_wwv.c on NetBSD there but I didn't
grok its purpose, looked like a simple rename of something inside
a structure to my naive eyes.

> By the way, using the audio mixer with audio drivers is
> strongly discouraged, as it introduces some nasty jitter.

There is a special branch of the ALSA Linux sound drivers for low
latency.  It promises latencies in the 0.5msec region.  I don't
understand how the mixer can possibly influence this, but maybe
I'm just ignorant.  Maybe the mixer works differently under Solaris?

Amazingly, the past couple of mornings I've been picking up WWVH
on 10MHz with great clarity.  I'm on the East Coast of the US so in
the evenings 10MHz is a deep swamp.  Like Steven I have the $40 Ramsey
10 MHz receiver and a couple of other cheap-o portable SW receivers
that can pick up 5, 15, and 20, but not frequency agile.  Maybe I can
feed 10MHz on the left and a different frequency on the right... gotta
get more isolation transformers :-)

Tim.



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