Strange bandwidth on CW @ 60 khz

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I’m preparing to receive the Christmas Eve transmission of the Alexanderson 1924 200 kW LF machine transmitter. They start the transmitter at 0730Z and the special message is at 0800Z on Christmas Eve, 17.2 khz

I just discovered something strange with my 6500. Tune to 60 khz, in CW. Set your bandwidth to 1.0K. Now increase it to 1.5K and take note how the bandwidth increases on the panadapter, as you would expect. No click on 3.0K – only the lower side increases, yet the upper side can be manually extended – Why?

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Posted 1 year ago

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Photo of k3Tim


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Confirm same behaviour at this station with 6500. The 3.0kc b/w setting performs this asymmetric operation on all bands.  Be that as it may, will see if the LF machine is heard...
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Jerry W4UK

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2 questions - 

1. Is it reasonable to expect to hear a signal - is propagation to USA normally observed at that freq?

2. Google says Flex max freq range goes down to either 20 or 30 kHz. But it can in fact tune to 17? (I can't test mine now.)

Jerry W4UK