Communication Concepts 2M 1KW Amateur Application Note - Manual (Page 11)

MRFE6VP61K25H MRFE6VP61K25HS 2 Meter Amateur
11
RF Reference Design Data
Freescale Semiconductor
THERMAL MEASUREMENTS
After one minute at 1 kW CW 44 volt supply at 80%
efficiency, with no airflow on the top of the board, the output
capacitor matching runs at 55°C, and the 10 Ω coax section
is around 90°C.
After 5 minutes “key down” CW, the highest temperature is
113°C on the 10 Ω coax section (Teflon cable is rated up to
200°C), output match capacitors do not show signs of
overheating.
If the board is run at levels higher than 1 kW CW or digital
mode, airflow over the top side of the board could help to
cool down coax and improve reliability.
As shown in Figure 14, the board was painted with black coating to correct for variations in emissivity
Figure 14. Reference design with black coating needed to obtain accurate thermograph images