Re: [Elecraft] KPS1500 fan noises

2018-05-21 Thread Bob McGraw K4TAX
There are basically two types of radial blade fans and specific application for each one.   Those that "blow" and those that "suck".  There is a difference in the design of the fan blades and the application for a specific fan.   Also some are designed to have "air over the motor".  This is a p

Re: [Elecraft] KPS1500 fan noises

2018-05-21 Thread Clay Autery
Roy, contrary to what the other guy said, that is a perfectly logical supplement to the OE cooling system.  ANYTHING that reduces the pressure at the exit venting will improve airflow over the heatsink. Increase inlet and exit free area and/or increase inlet pressure or reduce outlet pressure...

Re: [Elecraft] KPS1500 fan noises

2018-05-21 Thread Roy Koeppe
"Do the KPA1500 fans push air into the box? If so, why doesn't the KPA500 fan do that. If the KPA1500 fans pull out of the box why would it be appropriate to use an additional fan that opposes this airflow?" Yes, they do...which is also opposite of airflow in K3s. The idea of the additional