[MLB-WIRELESS] Access Point in a box

[Clae]

At 1:54 PM +1100 29/11/02, lkhoo at csc.com.au wrote:
>Michael said:
>
>>Hi there,
>>I am toying with the idea of moving my newly  acquired DWL900AP+ into a
>nice fibreglass electrical enclosure and putting it up  my TV antenna mast.
>My main concern is heat.  I can imagine that the  inside of the box >can
>get quite hot even on a slightly sunny day.  How do  you all find this?
>(those that have this type of arrangement). The last thing I  want is my AP
>dying from heat exhaustion!!

Shade it

>  >i had two ideas to combat the problem, first  is to pump cool air from
>inside the house, up 20mm flexible conduit,  circulate it in the box then
>out through a vent in the bottom.

Bear in mind that on a hot day, the conduit will get quite warm too.

>  >Second, and much more technical, is to use a  Peltier semiconductor heat
>pump to basically turn the box into a mini  fridge.

www.oatleyelectronics.com have these on special for $33 with a 
heatsink and fan right now.  Supposed to keep the case 25 degrees 
cooler than the outside air.  Condensation could be a problem, and 
you might want to include a temperature dependant switch of some kind 
to cut power to the Peltier on cooler days.  There's also a thermal 
control kit for the Peltiers available on the Oatley website IIRC. 
They work by pulse width modulation rather than simply switching the 
current on and off.  It is recommended that you use one to prevent 
thermal stress to the Peltier from constant heating and cooling, 
which can lead to failure.

>This would require a
>separate power cable as they draw more  current than could be >supplied via
>PoE.

The Oatley ones are about 50 watts.

How about a small solar panel wired straight to a PC case fan?  Sunny 
day = more cooling.  That and shade should help a lot.

Just thoughts and not based on any actual experience

Clae

-- 
-the lord is my shepherd, I shall not want - aum namah shivayam - 
allah u akhbar -
- in memoriam for the people of all nations and faiths killed in the 
Bali bombing -
- in memoriam for the 500,000+ people of all faiths and ethnicities 
killed in Indonesia by state forces supported by the US and Australia 
-
- in memoriam for the 200,000+ killed in East Timor alone

To unsubscribe: send mail to majordomo at wireless.org.au
with "unsubscribe melbwireless" in the body of the message