no recordings available
nice QSL letter from the collection of Maarten van Delft (1982)
------------------------------------------------------------
Callsigns:
HDN
HDN1
Frequencies Voice:
10420
18990
Frequencies Morse Telegraphy:
17590
Frequencies Radioteletype:
10447
11537
12087
12225
14472
15620
15622
17460
17517
17546.5
18036.8
20350
20411.5
20412
20531.5
20573
20722
20731.5
20854
22911
23431.5
Systems used:
50 Bd
75 Bd