Gina

Might be able to use the ESP8266 NodeMCU V1.0 ESP-12E WiFI Module (which I also have) if I use all digital inputs.  It has 10 GPIO digital pins but I don't know if any of these are reserved.

Sorry but that's wrong.  There will be two reed switches "on" when the magnet is between the two.  A side effect of this is to give 16 detectable directions.  It also means that there is no position in which all are "off".

One question about the ESP32 - does it matter which way the antenna points?  I'm think I could have it "portrait" style with the antenna at the top.

If I use a separate ESP32 for the wind measurements it can go in the plastic part at the top of the pole/mast with very short wires.  In fact I could simply run 9 wires and use 8 digital inputs on the ESP32 with internal pull-up thereby eliminating all the resistors.

I was thinking of using this circuit for the wind direction sensor but with lower value resistors and connected to the ADC inputs of an ESP32.  4 signal wires plus Gnd.

The question is though, how far can I run the wires safely without picking up interference.  I was thinking that, with the wind instruments mounted on the observatory, I could use one ESP32 for all the weather measurements but due to the size of the observatory this would involve wiring several metres long.  Maybe this isn't such a good idea.  It's not as if ESP32s are very expensive so maybe a separate one for the wind measurements would be better.

Well done Carole - superb image and under difficult conditions too. 

Good idea but better to use non-reversible connectors.

I'm using reed switches for the wind vane arranged in a cylinder with the magnet in a sleeve round it, the latter providing weather protection as well as holding the magnet.  The anemometer uses 4 magnets in the disc shaped hub and a Hall device.

With the wind sensors mast attached to the observatory I can now use one SBC to collect all the weather data with the wind data connected by wires.

Latest photos and CAD models.

A while back when I was using a Skywatcher NEQ6 Pro mount I found 12v from a PC ATX PSU was not quite sufficient.  I've used a 13.8v PSU since and no problem with that or the EQ8 I have now.

As you like Alan but they are advertised as buck converters.  I can see your point though - buck means reduce.

Buck converters can be set to any voltage up to a couple of volts below the input voltage.  But don't exceed the maximum input voltage (most seem to be 35v).  You can get step up buck converters too - useful if you want 24v from a standard 13.8v battery.

Yes, that's what I do.

+1

It should be correct about darkness but the weather is another matter!

Wont work with LED bulbs I guess...

The dome is very thin clear acrylic and has very little focussing effect - it only very slightly changes the focus.  Commercial units don't have anything to stop the greenhouse effect on hot summer days.  Of course, I know mine doesn't need to be built down to the standard of commercial units.  At least it's now waterproof and works pretty well.  As I said I may look into adding a cover later.  There are other benefits of a cover apart from keeping the sun off - such as insect and bird droppings and general "muck".  It would have to be remote controlled.  OK not beyond my capabilities probably but a lot of work.

On 01/07/2020 at 13:49, pete_l said:

Since we're talking in an astronomy forum, it seems to me that the best place for an anemometer would be close to your telescopes. That way you can assess the impact that wind has on them and on your imaging.
With experience you could then know when there were good conditions for viewing, or when it was too windy for the telescope to remain stable.

I have taken this on board and thank you for your suggestion.  For this and other reasons I have decided to mount the mast for the wind sensors on the SW corner post of the observatory.

Yep!  😀

Quite interesting tonight 😀

On NOW!

KStars.

I guess it would be possible to arrange a motorised cover for the dome.  I did think of it at one stage but decided it wasn't worth it.  I'll see how it goes and if I find the dome is affected by next summer I'll look at a cover.

I watched that on TV many many moons ago 😀