[time-nuts] any WWV audio recordings available? (synthetic WWV output fixed, I think)
dmw at weiten.com
Sat Feb 13 16:04:45 UTC 2010
Hi Scott et al.,
I compared the sound output from TG to an AU file provided by NIST, and
sure enough, it did sound weird.
I had a closer look at the TG customization that I had done, and indeed,
the whole u-Law audio compression thing was all messed up in my code.
The problem is that the original was written for a Sun workstation, and
it (apparently) used u-Law compression, or at least in the original TG
program, it was turned on.
In order to keep things the same and use the same tables, I thought I
had turned on u-Law compression, but apparently I did something
incorrectly. Therefore, I've now modified it to be linear, at least when
compiled for non-Sun systems.
So now the 100 Hz subcarrier should be 6 dB down, as I believe it is
supposed to be.
There are two sample files, 1 hour long each, in the ZIP archive at
http://www.weiten.com/time_nuts/synthetic_wwv-like_audio.zip . Please
give them a try/listen and let me know if it sounds more realistic.
Phone: (204)-888-1334 (home)
E-mail: dmw-at-weiten.com (home)
More information about the time-nuts