[arm-allstar] Repeater fan control...

[Doug Crompton]

Vendel,

   I leave all my fans run 24/7 but there are many ways to do it.  The
problem comes in if you just want it to run when PTT is asserted or for
some time after that.  A simple emperature switch is probably the easiest
way. Here is a controller -

https://www.amazon.com/Generic-Temperature-Control-Thermostat-Thermometer/dp/B00Q6WQJ2O

To have control using the Pi you could use a GPIO bit on the USB FOB.  This
would turn on the fan during PTT and off with no PTT. If you needed a
longer delay after PTT then you could time it in a script but then how do
you know you are really controlling the temperature accurately. There are
lots of examples out there but I really don't think this is the best way to
do it.

The reason the standalone temperature sensor would be better is that it
would maintain a specific temperature that you set based on where the
sensor is placed. Thus if the ambient changed it would still work well. If
you control from the Pi based on PTT even with some delay at PTT drop it
does not take into account the ambient temperature. If you added an input
for the actual temperature you mine as well buy one of these cheap
controllers! This is also complete independent of the Pi so it would work
with anything that needed to be maintained at a certain temperature.


*73 Doug*

*WA3DSP*

*http://www.crompton.com/hamradio <http://www.crompton.com/hamradio>*

On Tue, Feb 26, 2019 at 2:11 PM "Vendel via ARM-allstar" <
arm-allstar at hamvoip.org> wrote:

> I’m sure this has been covered before so please don’t rip my head off. 😉
> What is the best way to turn my repeater cooling fan (small 12 volt fan) on
> and off using my Pi node/ controller. Thanks, Vendel/ K2DSI.
>
> Sent from Mail for Windows 10
>
>
>
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
> _______________________________________________
>
> ARM-allstar mailing list
> ARM-allstar at hamvoip.org
> http://lists.hamvoip.org/cgi-bin/mailman/listinfo/arm-allstar
>
> Visit the BBB and RPi2/3 web page - http://hamvoip.org