davelectronic
- Dec 13, 2010
- 1,087
- Joined
- Dec 13, 2010
- Messages
- 1,087
I am not sure on a little issue, i have a small 25 watt linear RF power amp running on TX only, temperature concerns, or are my worry's needless.
Operation at full rated power the heat sink body is reaching about 80 degrees C.What i am wondering is the temp fine, oh i cant find the spec on the units safe temperature limits, anyway the SWR of my set up is less than 1.2 on the SWR meter, so reflected RF energy is being kept with in the units operating parameters there, but the unit is only small, do i need to add extra heat sinking, i dont know.
The rated supply voltage is 13.80 volts, i am running it at 12.00 volts, so very slightly under powered.
A lot of power transistors can operate above this temperature, that temperature observation is the case and not the junction temperature, i cant operate the unit and get a junction temperature, enclosure etc.
Can anyone advise on the safe area temperature of this 25 watt linear RF amplifier. are the 80 degrees C typical and normal, i am expecting heat, as it is a power amplifier, and the case is extruded aluminum. So in summary will it serve a useful life at this operating temperature, i am not looking for any 100% guarantees, more a sensible operational life, the unit came with spec on input output power, but no in depth data, i will post a page link of the unit, in the hope some one has some ideas.
Dave.D
http://www.moonraker.eu/Citizens-Band-Radio/Linear-CB-Amplifiers/MOONRAKER-L30-LINEAR-AMPLIFIER
Operation at full rated power the heat sink body is reaching about 80 degrees C.What i am wondering is the temp fine, oh i cant find the spec on the units safe temperature limits, anyway the SWR of my set up is less than 1.2 on the SWR meter, so reflected RF energy is being kept with in the units operating parameters there, but the unit is only small, do i need to add extra heat sinking, i dont know.
The rated supply voltage is 13.80 volts, i am running it at 12.00 volts, so very slightly under powered.
A lot of power transistors can operate above this temperature, that temperature observation is the case and not the junction temperature, i cant operate the unit and get a junction temperature, enclosure etc.
Can anyone advise on the safe area temperature of this 25 watt linear RF amplifier. are the 80 degrees C typical and normal, i am expecting heat, as it is a power amplifier, and the case is extruded aluminum. So in summary will it serve a useful life at this operating temperature, i am not looking for any 100% guarantees, more a sensible operational life, the unit came with spec on input output power, but no in depth data, i will post a page link of the unit, in the hope some one has some ideas.
Dave.D
http://www.moonraker.eu/Citizens-Band-Radio/Linear-CB-Amplifiers/MOONRAKER-L30-LINEAR-AMPLIFIER