Thank you for trying to help that quickly. I still do not fully understand:

1. I do usually set split=None. do I have to set Split=Rig? Using Flex6600 Do I have to make the radion run split?

The Split functionality is used to move the radio to the new frequency at the receive end, when the operator answers to the call by double clicking at the same time your radio will move reception to the new frequency. If you get that answer, then also your rig frequency is moved there for transmission. So the Split needs to be activated in both ends. At least I have understood in that manner.

By the way do you have a reason to use split=None? That setting may let audio harmonics to pass though your transmit filter, when you are using frequencies below 1500 Hz and for some reason overdrive your transmit audio path. K-series rigs may be less sensitive to overdriving due their output power control than typical transceivers, but still it is safer to user Split.

2. What is spinner control?

That control is only available on the MSK144 and fast JT9 sub-modes. No control available at FT8.

3. Using TX5, I did call CQ 200 4X4MF KM72 and was answered without any frequency change.

The CQ is normally sent using TX6 and I am not sure what is actually sent, when you type that text into TX5 as it is longer than 13 characters. I have typed the reception frequency directly into TX6 message just by editing it.

As I said this functionality should be tested with another station using Split before we know it is also works with FT8 and not only on those MSK144 and JT8 modes.

73, Reino OH3mA