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                                                        Noisy Cooling Fan Mod

ICOM have gone down a different route with PA cooling on this model. Normally a smaller fan would be used, usually a 12VDC unit being run close to it's intended operating voltage which makes for a very noisy arrangement. Here they have used a much larger fan, still a 12vdc unit but being run at about 6vdc with an initial additional "Kick" of 10vdc when entering TX mode to ensure that it starts reliably. With this arrangement a good air flow results but with less fan noise, however for many people including myself there is still too much noise. 
It is with thanks to Bjorn Eklund, SM7IUN who has managed to source a replacement fan which is "SILENT" when I say silent I can not even hear the initial 10v kick which the fan receives when first going to transmit, it is a Noctua NF-A8 PWM and is available on e bay in the UK for under £20 delivered.

​I have to say that this simple modification makes using the rig so much more pleasurable...............
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                                            This is what the new Noctua NF-A8 PWM fan looks like.

                                                           NB, Black is negative and Yellow is positive

Suitable 2 pin fan plugs with wire already attached are also available on e bay which can be used in conjunction with the new fan wiring making it a neat modification.

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