When I'm operating in the digital mode one of my favorite is RTTY.
I use a small (Ameritron ALS-500M) solid-state amplifier. I noticed
that when running RTTY it gets a little warm from the heavy-duty
usage. A few weeks after getting my 3D printer I ran across a fan set that I had left over from an old computer. It did not take long to come up with a mounting bracket for the amplifier. Runs a bit cooler now.

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