My DDutil temperature readings are 60 degrees celcius when i run maximum power.
But to be sure I power limited my radio to 75 watts in the radio setup.
I also typically use my amp. I set my flex to like 3 watts which drives my SPE 1K to about 175 watts.
With my lousy antenna this probably works out to an ERP of like 50 watts (sigh)
On JT-65/JT-9, it is another story. It often hear the fan switch up to high after several QSO's in a row in those modes. Though the temp never seems to get excessively high.
Btw... your rack mount looks very clean, neat, and tidy.
As long as you have adequate ventilation.....
Ken - NM9P
I usually start there. If I am not heard I bump up 1 watt on the flex. At 2 watts I get 80 from the amp. Again I figure ERP is about 50 perhaps. I keep working it up as I need to.
I find when I have the amp running about 80 W that I can get to almost anything on FT-8. There are a few nodes on my antenna that I just can't overcome.
But keep in mind that JT65 and the other modes in that software are "weak signal" modes. Not "low power" modes. While it is always a great idea to use as little as possible there is nothing wrong with adding power to get the contact done.
To my knowledge the 63/65/6700 are 100% duty cycle or close to it. The P.A is designed to be able to cool under full load. That being said if you were to place the radio in a very hot room or in direct sunlight once the PA exceeds the maximum allowed temperature the radio will go into protect mode until it returns to safe temperature.The new radios have an even better cooling system because of it’s lager heat sinks and lager fans.!