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=Selecting an equipment site=
See the website of your local Meteorological Bureau, the World Meterological Organisation, or in UK see [http://www.rmets.org/weather-and-climate/observing/guidelines-observing-0 Royal Meteorological Society]
== Where should I position the wind sensors ==
If you are mounting on a building of height 'h' above ground level, ideally the wind sensor should be at a height of '1.5 times h' agl.
If you are positioning away from a building or tree (or other object) of height 'h' (or the mean height of several objects is 'h'), then the distance away depends on which standard you are trying to meet, and can vary between 1.5 and 3 times 'h'.
In the UK, the recommended height is 10 metres. Advice varies on whether you should correct for a lower height.
== Where should I position the rain sensor ==
Officially the rain gauge should at a distance away of 2 to 4 times the height of each nearby object, (varies between different guidance). You can experiment, but for amateurs, no more than a metre off the ground (or roof if mounted above it) (not possible for Davis stations if temperature measuring criteria met) and at least a metre from any wall or solid fence whose height exceeds that of the sensor seems good.
You will find lots of discussions about wind effects, and rain shadows online, together with research for siting requirments in rural and urban locations.
== How do I protect my rain gauge against spiders or other natural problems ==
There is a lot of discussion on the [http://sandaysoft.com/forum/viewforum.php?f=16 Homebuilt forum].
== How do I get good temperature and humidity measurements ==
The international standard states ambient temperature/humidity is measured at 1.25 metres above ground level, protected from direct sun radiation (and direct rain), unless you are measuring soil or ground temperatures.
Modern Stevenson Screens are uPVC constructed with a black interior and a white exterior.
There is a lot of discussion on the [http://sandaysoft.com/forum/viewforum.php?f=16 Homebuilt forum] about different approaches, and the problems with out of the box instrumentation from the different manufacturers.
== Pressure ==
Varies with altitude and temperature, but no significant variation with spatial position with regard to nearby fixed bulky objects. Often measured indoors, only consideration will be trying to avoid any forced ventilation or extraction as such air moving systems could have different pressures on intake and outlet sides. Equally operation in close proximity to fast moving (road or railway) vehicles or tunnels can distort readings.
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