Tnx for the input.
WSJT- is NOT a LOW POWER MODE..
it is a WEAK SIGNAL MODE
Your Flex is rated at 100W @100% duty cycle
Running barefoot I typically run 100W on WSJT-X for hours on end with no issues whatsoever.
However... if you are trying to work a really weak one say -24 or less then you need all the power you can get out.. I have a 10+dBi gain beam on 40M -6M... even so, I put on the AMP and run 1500W when I worked DX in the -26 to -30 range or they will not hear me.... need to have ERP in the 10+KW range to be heard.
Before the uninfomed QRP Police rap me across the knuckles.. you also need to make sure that you are NOT SPLATTERING when you run power. Splatter makes it much more difficult for others to copy you which effectively defeats using power.
To avoid splatter usually means that you need to reduce the DAX TX levels so as to minimize your sidebands. It also helps to have a local ham with a Flex nearby who can SEE your output and tell you if you are splattering...
Run the Flex PA at 100%, vary the transmit power level of the TX channel gain.
Ambient air temp at the transmitter has a lot to do with the 6500's response to the transmission duty cycle. In warm air my 6500's fans will go up to full speed at about the 40 second mark, maybe sooner. In cool air, they never come on. I assume that the radio will not permit itself to harmed by high duty cycle temps, so I wouldn't be concerned about it. I'm sure Tim or someone will chime in if this is not the case.
High duty cycle modes are part of the ham radio landscape. The radio is designed to handle it.
Howard not a shot at you my friend just having some fun.
JT65. I normally leave the power on SSDR at the max, and modulate the power from the WSJT-x power control. The radio never kicks into high fan speed even at that setting.
BTW my antenna is a Cushcraft R-8 vertical, and using the ATU..
The radio has thermal protection logic to prevent damage from overheating. If you are not getting errors, I wouldn't worry about it.