AVR-Chat

Hello, John -

GPS does seem to be the increasing choice for time/date
data. That said, most technological countries still do have
local or regional standard time broacasts. The trend seems
to be to VLF for simple, low-cost receivers. One downside
to these is that, beyond a hundred miles or so, the signal
becomes a night-only affair. This means that the clock has
to run using its local time-base and allow periodic
updating. 

Here in the US, the change-over between standard and
daylight savings time has been pretty consistent over a 10+
year period. Clearly, you would want to be able to program
this in and have access though some kind of comm link. I
suspect that you would want  such a link, anyway, because
almost anything might happen to the sign (bolt of
lightning, anyone) and you may need to be able to reset it
or diagnose problems under more comfortable circumstances
than hanging on the side of a building!

Jim


On Thu, 15 Jun 2006 09:33:28 +1000
 John Samperi <samperi@ampertronics.com.au> wrote:
> G'day all
> 
> 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
> 
> ********************************************************
> Ampertronics Pty. Ltd.
> 11 Brokenwood Place Baulkham Hills, NSW 2153 AUSTRALIA
> Tel. (02) 9674-6495       Fax (02) 9674-8745
> Email: john@ampertronics.com.au
> Website  http://www.ampertronics.com.au
> *Electronic Design * Custom Products * Contract Assembly
> ********************************************************
> 

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