This directory contains voice clips assembled to generate the time
announcements starting at 45 (WWVH) or 52.5 (WWV) seconds past each
minute, giving the time at the start of the next minute. For
simplicity these files are in raw PCM format, converted from their
original mp3 format. The file parameters are:

bits/sample: 16
channels: 1
sample rate: 48 kHz
encoding: signed-integer, linear PCM
byte order: little endian

The file names should be self-explanatory; Jane Barbe's voice for WWVH
are in the h_ files, while John Doyle's voice for WWV are in the v_
files. There is one file for each number from 0 through 59, plus these phrases:

"at the tone"
"minute"
"minutes"
"hour"
"hours"
"coordinated universal time"

(A few other unused files from the original source are included, I
might use them someday. I already had good off-air recordings of the
station IDs so I don't use those here.)

Because these are stitched together on the fly, the timings are
hardwired in the wwvsim.c source file. Absolute offsets within the
minute are used for the start of the "at the tone" segment, the start
of the minute and hour numbers, and the phrase "coordinated universal
time". The units phrases ("minute", etc) are currently concatenated
directly onto the end of their corresponding numbers as this seems to
better match the broadcast cadence, but this still needs a little fine tuning.

If you are using wwvsim as a local reference signal for correlating
with off-air reception, *do not* generate any local audio
announcements as they are guaranteed not to line up in time and
amplitude precisely enough. Disable all voice announcements with the
--no-voice option to 'wwvsim'.

Phil Karn, KA9Q
June 2026
