[TenTec] Quieting fan

[Ken Brown]

Hi John,

I'm glad you have made some good measurements that seem to indicate you 
are still getting sufficient cooling at the slower fan speed. I am 
curious what the meaurements were before the resistor modification was 
made. Is the "before" in your list of temperatures before 5 minute 
key-down, and not before the modification? Seems like only 6 degrees 
temperature rise after 5 minutes of key-down is not too much. You might 
want to consider a switch to bypass the resistor conveniently for 
contest or other higher duty cycle operation. My Titan has a fan speed 
switch on the power supply, and that is exactly how I use it.

DE N6KB

>I checked the case temperature before during and after a 5 minute continuous key-down @ 450 watts into a dummy load. The results; recorded with a Raytek infrared thermometer: 
>*before; case intake 95 degrees F, case exhaust 115 degrees F.
>*during; intake 95 degrees, exhaust 121 degrees F
>*1 minute after; intake 95 degrees F, exhaust 118 degrees F
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