[hpsdr] To suck or to blow, that is the question

[Ron Kolarik]

I'm pretty sure the third lead on those fans is a tachometer output, the MOBO
uses it to sense speed and adjust up or down for temp.  Then again I may be wrong.

Ron
k0idt


> Message: 8
> Date: Sun, 12 Jul 2009 00:21:14 -0500 (CDT)
> From: John Koster <w9ddd at tapr.org>
> Subject: Re: [hpsdr] To suck or to blow, that is the question.
> To: Luis Perdomo <luisfp at gmail.com>
> Cc: hpsdr at lists.openhpsdr.org
> Message-ID:
> <Pine.LNX.4.44.0907120018260.5085-100000 at localhost.localdomain>
> Content-Type: TEXT/PLAIN; charset=US-ASCII
> 
> Good for a 'dumb' fan, but many of those I can buy at Fry's have a control 
> lead which when left unterminated lets the fan run full speed.  If you 
> have the right control voltage going to it, you don't need all the 
> circuitry shown in your link.  Guess one needs to find the schematic of a 
> Mobo and duplicate that circuit if it's not buried in one of the large 
> ICs.  Perhaps it's a signal out of the processor these days?  
>