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How cool your FT-840


Staff member
Apr 6, 2005
Sierras Near Yosemite National Park
Here is a simple mod to provide some additional cooling to the radio chassis.

Remember that the original fan is only good when it is being transmitted, in rx which is most of the time, underneath it is very hot because the voltage regulators are at the bottom of the radio.
This heating tends to rise by convection heating all electronics, chassis and IF board.

With this simple resource, the FT-840 runs cooler, the feed comes from the connector 13.5V on the back of the radio.

Important note:so as to reduce dust inside the radio, use the fan to draw from the inside, this effect takes all that hot air from inside the radio.

Note: Do not forget to lift the feet of the radio, so the fan will not hit the bench.

Pictures and Mod Provided From PU4ASL.



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