This is kind of off-topic and technical. 

If you have to only monitor air and/or water temperature you should turn off your
attention from weather stations and go for temperature
sensors/transmitters which are cheaper. A tipical "weather station"
should include humidity and pressure sensors, local data storage
capabilities and, optionally, local data display. This makes them really
expensive. 

A simple temperature measuring system should include
some cheap semiconductor temperature
sensors like LN35, one or two opamps, and an 8 bit microcontroller (does
Atmel still manufacture AT90S4433 ?). If the distance between computer
and sensors exceeds 10 meters, data transmittion should be made via
an RS422 or RS485 interface. The RS485 requires only two wires (twisted
pair). Data can be transmitted over a distance up to 1.5 miles. There
are cheap RS232 to RS485 converters, but a good one should have optical
isolation. The whole device should fit in a soap box, but additional
precautions should be taken if the device is intended to work outdoors.

The data transmittion protocol I ussualy employ for such devices, is a
MODBUS subset. Quite simple to implement on any OS including DOS. The 
only drawback with DOS is that one has to dedicate a computer only to 
this acquisition job, while in Windows or Linux the respective program
should run in the background, leaving the computer ready for fullfilling 
any other task, including the respective data processing done by any
other program.

Regards 
C.B

On Sat, 25 Jan 2003 22:56:46 -0700, [EMAIL PROTECTED] wrote:

> Hi Bastiaan,

> On Sat, 25 Jan 2003 "Bastiaan Edelman, PA3FFZ"
> <[EMAIL PROTECTED]> writes:
>> A variety of electronic measuring instruments could be coupled to
>> arachne eg by using the game/printer/RS232 ports.
>> DOS is not dead, neither is BASIC ;-))

> Can you guys make some real simple (and real cheap) weather stations?

> I had a project where I wanted to monitor air and water temperature over
> time and have the computer keep track of all the information. I found
> some weather stations, but they were all about $300 (USD) and required
> Windows.

> I needed something real cheap for village horticulture projects. I also
> had thought that it would work by reading the ports, but it was all too
> far over my level of expertise.

> A DOS or BASIC program would be good, especially if it can be done with
> recycled hardware.

> Bob

> -

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