Re: Data vs SSB


ve3ki
 

AFSK A is LSB by default. Instead of leaving the rig in AFSK A "reverse" (USB, but still AFSK A), you should change the data sub-mode to DATA A (which by default is USB). The reason: The dial frequency displayed by the K3 in DATA A is the suppressed carrier frequency, as expected by your software, whereas the dial frequency in AFSK A is the RTTY Mark frequency. This means that your FT8 software will tune the rig to the wrong frequency. A dial frequency of 28.074 MHz in AFSK A "reverse" will tune the rig to the same actual frequency as DATA A set to 28.071875 MHz (assuming a RTTY Pitch setting of 2125 Hz), which will not get you many FT8 contacts.

73,
Rich VE3KI


On Fri, May 25, 2018 at 03:14 pm, Larry wrote:
Peter,

When i looked at the data mode, it showed AFSK A and not data A and it
was set on LSB.  I changed it to USB so now will see how things work
when 10M opens up again.

Tks for the suggestion.  {slow down a bit, you might miss some DX!}

73

Larry
W0OGH



On 5/25/2018 12:16 PM, Peter Kohl wrote:
Hi Larry,

Just a short one (am in a hurry...)
Check AGC on/off - can have drastic effects
Check if the right xtal-filters are activated for 10M

73 de Peter ON4EZJ

On 25/05/18 18:12, Larry wrote:
Here's a new one.  I was working 6M FT8 mode this morning and when it
went out shifted down to 10M digital, FT8.

On 6 and the other bands i use data mode with FT8 but when i shifted to
10M data mode would not decode any signals.  I had to shift to USB.
Nothing else as far as controls changed, it would just not decode
anything on data mode.  No idea what the heck is going on there. When i
was in data mode, i could see signals to decode on the screen but the
"decode" button in WSJT-X would only flash quickly.  Changing to USB
allowed me to copy or decode signals.  Data mode was not reversed so i'm
stumped by this. Probably something simple but i just can't see it.


larry

W0OGH







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