[hpsdr] Pandora Fan

[John Ackermann N8UR]

Jeremy McDermond wrote:

> I was mainly looking at PC fans because I wanted to grab one that had 
> the temperature control on it.  It just made sense to me to have a fan 
> in there that wouldn't run full speed all the time even when I'm only 
> receiving and such.  There are tons of 80mm and 120mm fans on the market 
> that have all that built in.  I bought mine for like $15, and it had the 
> cool blinky lights.  :)

Pennywhistle might change things, but the vast majority of the heat 
dissipation in the current HPSDR system is in LPU dropping 13.8 down to 
5 volts at about 1.3 amps, and secondarily the ADC in Mercury (which is 
using a lot of that 1.3A).  That heat is being generated in RX as well 
as TX.  The Penny TX amplifier runs from the 12 volt supply, and doesn't 
generate much heat (in comparison).

So, the current configuration isn't affected all that much by TX duty 
cycle.  However, with Pennywhistle added temp control might prove more 
beneficial.

John

PS -- No offense taken!

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