PTT Khartoum :
in this recording from Paul Hawkins you hear Khartoum calling for London (ca 1968)
from the files of Hajo Russow: english & arabic male voice mirror (1969)
they used their own QSL-card for verification (Lars Lundström, 1972)
------------------------------------------------------------
Callsigns:
STL **
Frequencies Voice:
11525
13430
20800
Frequencies Radioteletype:
9220
11525
15710
18048
18084
Systems used:
50 Bd