I open the topic because the cooling of the transmitter is of crucial importance. An undeniable fact for the long life of the transmitter.
Especially emphasized on the upper part of the amplifier board soldered elements on the printed circuit board

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It depends on what performance level you want: long life or cheap cooling.
The most sensible approach is to choose long life. You need to find fans with ball bearings. These fans don't advertise that, so they use greased plastic, that after a few years (or months) get stuck and stop rotating.
The other nice thing to do is mount several small fans, just in case one quits working.
Flow rate has its tradeoffs: low Rpm means less mechanical wear and less dust sent through the vent canal. Faster flow means better cooling that reaches the inner parts of the rig.

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Krakatoa wrote: ↑Sat Jul 06, 2024 8:18 am It depends on what performance level you want: long life or cheap cooling.

And noise level as far as I am concerned

I like the Delta FFB0812EHE 80mm*80mm*38mm 12V
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Theres usually regulators too, that go to a display, the 3 legged kind can generate a lot of heat, enough to fry a sausage, will generate heat inside of enclosure, you can bring the fan close to the output mosfet, if your lucky to have temperature gage on the transmitter, reduce the temperature, also reduced noise, I did it with the pcs the temperature went below 40, the speed would also vary depending on power been used, slower fan means less noise.

alot of people would swap out the fan on the cze, it would sound like crop sprayer going by, noise is a problem if you're with the transmitter, or maybe it could alert people to it only problem if its not meant to be there.