Yeah - I had one of these working on an old Centos5 install of Allstar.
At some point, the space weather folks required an https connection and the SSL in Centos 5 did not support the required encryption - and apparently could not be upgraded. So it stopped working.
Basically what you need is:
wget https://services.swpc.noaa.gov/text/wwv.txt wwv.txt
massage the wwv.txt text file a little then feed it to your favorite speech synthesizer to make 8K audio.
I used “swift” by cepstral.com, which was rather expensive as I recall. There are free text-to-speech options which probably don’t sound as good.
I also found it useful to put the resulting sound file through a 300 Hz high pass filter before sending it on the air.