60 Meter Operation with Flex Radios
We regularly receive questions about operation on 60 Meters with FlexRadios, such as "Why won't my radio transmit on 60 meters"" or "When I try to operate FT8 on 60 Meters, it won't transmit."
In the US, FCC Regulations require no more than 2.8 KHz bandwidth, ceneterd at 1.5 KHz above the "Carrier" frequency of a SSB or DigU signal.
This means, that the Transmit Filter Low Cut must be set no lower than 100 Hz, and the High Cut must be set no higher than 2900 Hz.
If you are outside these limits, or if you tune up or down from the assigned carrier frequency, then the FlexRadio will disable your transmitter in order to keep y ou from transmitting out of band.
If you are operating FT8 or FT4, then it is advised that you set the "Split" option in WSJT-X "File>Settings>Radio" Menu to NONE.
If you select "Rig" or "Fake it," then WSJT will move your Slice frequency off of the assigned carrier frequency, and the radio will inhibit the transmitter.
This is important especially when running "Fox & Hound" because the standard setting in Hound mode is Rig or Fake-it. You will need to change to NONE when operating on 60 Meters.
NOTE: If you are using a narrower transmit filter, you CAN adjust your carrier frequency slightly, as long as your "carrier frequency" plus the High Cut, (or minus the Low Cut) will not exceed the authorized band limits..
For example:
If you have the Hi Cut set at 2400 Hz, then you can tune the slice up by 500 Hz and still be in-band.
If you have the Low Cut at 300 Hz, then you can tune the slice down by 200 Hz and still be in-band.
SUMMARY:
on 60 Meters....
Set Low-Cut no lower than 100 Hz.
Set High-Cut no higher than 2900 Hz.
Stay on the assigned frequency.
Set WSJT-X "Split" setting to NONE. (Don't use "Fake-It" or "Rig" on 60 Meters)
It is best to save a special Mic Profile for "60 Meters SSB" and another one for "60 Meters DigU" so that these parameters can be remembered.
Good luck.
Ken Wells - NM9P