Ref (a) FT8 DXpedition Mode User Guide, by Joe Taylor K1JT - May 16, 2018
The ref (a) User Guide indicates that the Hounds should make initial calls anywhere in the range of 1000 - 4000 Hz. Also, in the detailed Instruction for Hounds, item #6 it talks about “set the high frequency end of the waterfall to 4000 Hz". However the waterfall in receive on my K3 is limited to between 300 and 2750 Hz even if I increase the bandwidth on the K3 to read 4.00 (because of the actual bandwidth of my widest roofing filter) in the main receiver.
Seems to me that one could make use of the wider AM filter in receive and now I, as a Hound, can see the frequencies of the other Hound signals up to approx 4 KHz and find a opening to call.
Since the K3 Utility program provides an easy way to specify which of the crystal filters (up to 5) is enabled for receive in each mode. One should be able to just put the AM filter into position 1 and enable it for Data A receive.
In my case I would have to move the AM filter from the subRx to the main Rx in order to do this configuration change.
Before I dig into the station to make this change, I wondered if anyone had tried using the AM filter for receive and how it worked.
BTW a similar question is asked in the Answers to Frequently Asked Questions, Item 4 in the Ref (a) guide but it addresses the audio TX frequency and the shift automatically performed by the software. My question relates to “seeing” the full audio range on receive.
73, Doug VE3MV