On 15/11/2011 08:51, Dave Liquorice wrote:
On Tue, 15 Nov 2011 01:52:05 +0000, Timothy Murphy wrote:

It's a pity none of the cheap weather stations seem to work with
WiFi.
It would be nice to see the temperatures on the computer.

Would add a whole new sub-system to be "general public user
friendly". It would need a TCP/IP stack, web server and processor
capable of handling that. I suspect that these cheap weather
stations
just have a "weather station chip" rather than a GP processor
suitably programmed.

Maybe a Bluetooth chip?

Well it would provide the radio part but you'd still need a processor
capable of running a TCP/IP stack and webserver. One could dispense
with teh web server and use a host PC to establish a connections to
or from the Wx station to get the data and then provide the data
processing and web server but how many ordinary users have a web
server on their PC? To be useable for the masses the Wx station would
require to just coonect to the local lan configure itself and then be
contactable via a web interface.

LEDs, going dim, not heard of that, they temd to work or not work.

Actually the high power LEDs do dim a bit with age. The light flux out
of the junction is strong enough that combined with the thermal load it
will denature the clear epoxy plastic of the packaging. Not normally a
problem with ordinary display indicator LEDs though.

Do
you really mean LEDs? They tend to be power hungry and all the
weather stations I have seen have LCD displays. The latter can
lose
contrast with age, there *might* be a contrast adjustment inside.

Could perfectly well be LCD displays.
I'm not too clear on the difference.

LEDs are Light Emmiting Diodes, they emit light from the segments
that make up a character or indicator. LCDs reley on a reflective
backing and or a backlight that illuminates the entire display area
with the segments appear black against the backlight. Some LCD
displays are the inverse, a generally black background through which
the black shows for the charcter segments.

Is there any way of reviving an ancient LCD display?

There might be a contrast adjustment inside the unit.

Although usually swapping the battery for a fresh one will be good
enough to restore sufficient LCD display contrast. If the LCD display is
so old that its liquid crystals have given up the ghost then there is
not much you can do about it. The LCD strip thermometers tend to fail
that way either showing every temperature or none.

--
Regards,
Martin Brown