Repeater Cooling Fan

[JeepZJ]

I'm assuming I only need a fan on the transmitting radio.

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 I am also assuming I need something that will not mess with the radios via buzzing, humming or other nasty sounds.

 

Will a computer fan work for this task?

 

I'm going to install a normally closed adjustable fan switch on the heat sink....what temperature should I set it to turn the fan on?

[rfmedic]

Regular muffin fan is fine - depending on the quality of the fan you may need a filter cap on the DC fan (small chicklet across the +/-) to keep any buzz out of the audio if it arises. Also keep the power to the fan as close to the power supply as possible and routed away from the audio chain.

If you are going to make it thermostatically controlled, around 90-100F is a good turn on time especially for a mobile.

 

RfMedic

[JeepZJ]

90-100F seems a bit cool considering the summer temps would cause this to run all afternoon in July & August even when the repeater isn't used.  A/C is not an option for this Off-Grid location.  The building will be well insulated but it also will be in direct sunlight all day.