VE7FMN, Fred sent me a Cooler KX Plus heatsink to try out for my Elecraft KX3, and I made a video of the simple install process. This heatsink really is made quite well; the finish and machining compliment the KX3 nicely. Here is the video of the installation procedure, plus a test at the end:
For a simple test, I ran the KX3 on 20 meters at 10 watts, FM mode into a dummy load until the rig gave a Hi Temp warning and folded the power back to 5 watts. With the stock heatsink, the Hi-Temp warning occurred after 8 minutes and 46 seconds. With the Cooler KX Plus, the keydown time extended to 27 minutes, 36 seconds until the warning. The starting PA temperature for both tests was 28 deg. Celsius and the rig folds the power back at just over 60 degrees.
It should be noted that the the higher you go in frequency with the KX3, the quicker it heats up. Adding an aftermarket heatsink allows you to operate at full power using high duty cycle modes, such as FM or many digital modes. There are several aftermarket heatsinks available; an independent performance review of each can be found here: http://www.ve7fmn.ca/this-is-cool/pdfs/performance_page/head-to-head.pdf.
The Cooler KX Plus black heatsink is currently $118; the smaller Cooler KX Lite is $85 and can be ordered direct at http://www.ve7fmn.ca/
For a simple test, I ran the KX3 on 20 meters at 10 watts, FM mode into a dummy load until the rig gave a Hi Temp warning and folded the power back to 5 watts. With the stock heatsink, the Hi-Temp warning occurred after 8 minutes and 46 seconds. With the Cooler KX Plus, the keydown time extended to 27 minutes, 36 seconds until the warning. The starting PA temperature for both tests was 28 deg. Celsius and the rig folds the power back at just over 60 degrees.
It should be noted that the the higher you go in frequency with the KX3, the quicker it heats up. Adding an aftermarket heatsink allows you to operate at full power using high duty cycle modes, such as FM or many digital modes. There are several aftermarket heatsinks available; an independent performance review of each can be found here: http://www.ve7fmn.ca/this-is-cool/pdfs/performance_page/head-to-head.pdf.
The Cooler KX Plus black heatsink is currently $118; the smaller Cooler KX Lite is $85 and can be ordered direct at http://www.ve7fmn.ca/
