Sudan reported on 639.
Most or all radio stations in Khartoum have reportedly been off the air since the fighting started on 15 April. BBC Monitoring observed state radio’s main channel suddenly go silent on satellite at 2217 GMT on 15 April.
But Saudi Arabia’s Al-Arabiya TV now says 639 AM has resumed transmissions:
https://twitter.com/ahmadhgurashi/status/1651911346772901889
Chris Greenway to WOR iog (2023-04-28)