In article ,
B. Otten wrote:
Listening moments ago to the Voice of Viet Nam on 6.175 mhz and during
the broadcast there are two alternating tones separated by 5 secs.
Beeeep (higher tone).....Booooop (lower tone). Anyone know what's up
with those tones? Jamming? Time would be 0100 UTC. Story was about the
10 year anniversary of normalization of relations with the U.S.

Try listening to 5975 at about 2:55 UTC when Delano is firing up
the transmitter for the hour they do the BBC to the Americas.
If it's the same tones, it's part of their startup procedure.
(They don't seem to care if they're stepping all over a transmission
in progress from another site).

Mark Zenier Washington State resident