AVR-Chat

John Samperi wrote:
> G'day all

Hiya,

For the cost of an OEM GPS module (<AUD100) it is probably easier to just add it 
into the clock module & keep it all self contained.

Cheeep plastic Stevenson screens for the temp sensors are easy to come by, until 
you need to find one in a hurry for an email reply ;-), if all else fails make a 
stack of white plastic saucers with the centre cut out & 3 threaded rods with 
spacers between the saucers spaced around the outer circumfrence.

Main idea is to create a ventilated space that is out of direct sunlight and 
clear of radiation from the screen surface. The idea of the screen construction 
is to minimise the exposed area of the outer wall to sunlight.

Alternatively try the zone beneath the display although if it is wall mounted 
then you will have the measurement distorted by the warm air rising up the face 
of the building.

Cheers

Don


> 
> I'm looking into a project for an outdoor time/temp/date giant
> display (20" high possibly).
> 
> As the unit will be mounted on the side a multistory building as
> I understand, I don't think the client will want to get a cherry
> picker or climb a window washing lift to reset the time twice a
> year to cater for the dreaded daylight time changes.
> 
> So I'm looking at 3 options:
> 
> 1) Have the display connected to a computer which will be always
> on with a small application that will send time and date out every
> minute to the display via an RS485 link. This would take care of the
> daylight saving automatically.
> 
> 2) Have a plug in keypad somewhere at ground level.
> 
> 3) Best option-have an off air time and date signal like the one
> on my PVR. I know that in some parts of the world you can get this
> kind of signal but from my research it seems to be giving way to
> GPS time signal.
> 
> So my question is has anyone used some kind of receiver that is
> dedicated to simply receive this kind of signal? Any experience?
> 
> Also as far as temperature reading is concerned, a simple temperature
> chip on the PCB may not work because the air temp inside the case would
> be much higher than the actual air temp. Again any hints on this? I'm
> thinking along the lines of a small box with lots of holes and a temp
> chip inside that may work well. Again I don't have any experience with
> outdoor temp measurements so any guidance would be appreciated.
> 
> Of course I may not get the job but the research is interesting. :-)
> 
> 
> Regards
> 
> John Samperi
> 
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> Email: john@ampertronics.com.au
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