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

[Willi Reppel]

Hi all,
A similar discussion about direction of air flow, speed control and fan 
noise was going on once on the Flex-Radio reflector 3-4 years ago. The speed 
control of many fans generated square waves and electrical noise and a 
network of resistors and capacitors was recommended to get rid of the noise. 
Relevant info is buried somewhere in Flex-Radio´s knowledge base.

Best 73
SM6OMH  Willi

----- Original Message ----- 
From: "John Koster" <w9ddd at tapr.org>
To: "Luis Perdomo" <luisfp at gmail.com>
Cc: <hpsdr at lists.openhpsdr.org>
Sent: Sunday, July 12, 2009 7:21 AM
Subject: Re: [hpsdr] To suck or to blow, that is the question.


> ***** High Performance Software Defined Radio Discussion List *****
>
> 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?
>
> On Sat, 11 Jul 2009, Luis Perdomo wrote:
>
>> ***** High Performance Software Defined Radio Discussion List *****
>>
>> Speed & temp controller for muffin fans and the like:
>>
>> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=120444743805
>>
>> Luis, NZ5U
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>
> -- 
> 73,
> John, W9DDD
>
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