Humidity Transducer?

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#1
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Feeling bummed 'cause I have not made anything for a long time. I seem to have lost interest in trains and can't think of anything to make not train related.

 

How about a weather station?

 

I have some hall effect sensors -- this will do for counting anemometer speed.

Lots of IR leds and sensors -- I'll make a gray code encoder ring to connect to the weathervane to give me 8 compass points.

LM35 temperature sensor -- For temperature.

Just ordered some MEMS barometers. Oh, they have temperature sensors built in. Might not use the LM35's

 

I'll power the outside unit with D batteries. Use NRF24L01s to transmit data to display inside. Use TFT for inside display.

 

But how to sense humidity?

 

(Yea, it's an autistic thing to suddenly use a 20-year "special interest.")

 

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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Sensirion, (SHT71), has great Temp and %RH sensors.

 

Bosch, (e.g. BME280), also has really cool Temp, %RH, and Barometric Pressure sensors.

The sensor itself is incredibly small, so buy a breakout board for the sensor.

 

JC

 

Below is a repurposed PCB when I was working with the BME sensor:

 

 

 

The PCB below shows the little pink/purple BME breakout PCB at the top edge of the main PCB:

 

Last Edited: Fri. Jan 21, 2022 - 03:01 AM
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What happened to the photographic interest? surprise

John Samperi

Ampertronics Pty. Ltd.

https://www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

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Pleased to see you back here Tom. Belated Happy New Year to you.

Ross McKenzie, Melbourne Australia

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Welcome back, hope all is OK.

 

As already suggested, go for the BME280. It is easily interfaced, IIRC was very current efficient and small, so would easily fit anywhere. Ada-Fruit or sparkfun should have breakout boards sowill make 'playing'  a lot easier.

I know the interest part... have been working on a datalogger, decided to make a PCB using an ARM processor to have a play with that and after I got to a certain point interest just disappeared. It recently has somewhat come back as I found a use for the thing so now seem to be wanting to make it work again.

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BME280 for sure, here it is, pink square on the right.

 

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Torby wrote:

But how to sense humidity?

 

Go old school and make something based around the Wet Bulb technique. Much more challenging than just buying a purpose-built sensor.

#1 Hardware Problem? https://www.avrfreaks.net/forum/...

#2 Hardware Problem? Read AVR042.

#3 All grounds are not created equal

#4 Have you proved your chip is running at xxMHz?

#5 "If you think you need floating point to solve the problem then you don't understand the problem. If you really do need floating point then you have a problem you do not understand."

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plenty to choose from; eg,

 

Top Tips:

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  3. Wrong baud rate is usually due to not running at the speed you thought; check by blinking a LED to see if you get the speed you expected
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https://www.sparkfun.com/product...

A complete WX station, I know, it takes all the fun out of it, but it's open source, so look it over and take what you need.....

Glad to see you back!

 

Jim

 

 

FF = PI > S.E.T

 

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Still do that! It's a little too cold for barefoot droning right now

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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valusoft wrote:

Pleased to see you back here Tom. Belated Happy New Year to you.

 

Hoppy Gnu Ear to you!

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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js wrote:

What happened to the photographic interest? surprise

 

A little cold for barefoot brats!

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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Brian Fairchild wrote:

Torby wrote:

But how to sense humidity?

 

Go old school and make something based around the Wet Bulb technique. Much more challenging than just buying a purpose-built sensor.

 

Wet pad around one bulb and swing it around on a string!

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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awneil wrote:

plenty to choose from; eg,

 

 

Why didn't I think of SparkFun and Adafruit?

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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Check your PM's Tom.

 

Jim

I would rather attempt something great and fail, than attempt nothing and succeed - Fortune Cookie

 

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Please Read: Code-of-Conduct

Atmel Studio6.2/AS7, DipTrace, Quartus, MPLAB, RSLogix user

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What about photography and droning? Well....

 

https://www.youtube.com/watch?v=...

 

 

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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All the electronic parts are here. I got the HTU31-D QT from Adafruit. Strangely, they refused to ship to my UPS box where everything is kept in a secure place, preferring my mail box.

 

Some mechanics are done. Here I 3d printed the rings of my Stevenson screen. Maybe I should move this to "Projects?"

 

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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Tom, you should paint your screen a highly reflective white colour for most accurate performance.

Ross McKenzie, Melbourne Australia

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valusoft wrote:

Tom, you should paint your screen a highly reflective white colour for most accurate performance.

 

It IS a highly reflective white. Just a silly photographer who did not change the white balance for my "Warm white" LED lighting. But I might paint it exterior white anyhow.

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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Torby wrote:
... from Adafruit. Strangely, they refused to ship to my UPS box where everything is kept in a secure place, preferring my mail box.
UPSindecision  USPS?  If yes then had the same issue with Battery Tender®; local postmaster gave me the physical address of that post office.

<USPS office address>

#<USPS box>

city or town, state, USPS zip code

 

That postmaster is keen on scanning parcels and such; tracking updates very quickly.

USPS.com® - USPS Tracking®

 

Part of the most recent conversation with that postmaster was parcel security; here, parcels left on your front porch can be blown off the porch by the wind.

 

"Dare to be naïve." - Buckminster Fuller

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I think you can get a mail box at some UPS stores.  I thought they bought out Mail Boxes Etc., but it seems they are still around too.

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gchapman wrote:

Torby wrote:
... from Adafruit. Strangely, they refused to ship to my UPS box where everything is kept in a secure place, preferring my mail box.
UPSindecision  USPS?  If yes then had the same issue with Battery Tender®; local postmaster gave me the physical address of that post office.

<USPS office address>

#<USPS box>

city or town, state, USPS zip code

 

That postmaster is keen on scanning parcels and such; tracking updates very quickly.

USPS.com® - USPS Tracking®

 

Part of the most recent conversation with that postmaster was parcel security; here, parcels left on your front porch can be blown off the porch by the wind.

 

 

I have a box at the local UPS store. Adafruit considers such things fraudulent, so I had to have them ship to my house.

 

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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I have a handy next door neighbour laugh. So far this week he's had a box of electronics from China and a paraglider returned from its bi-annual legal test.

 

There's a DHL/Bundespost locker block at the supermarket down the road, but for some reason it's never offered as a destination when we get to the 'your parcel is arriving soon, where would you like it?' stage.

 

Neil

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barnacle wrote:
and a paraglider
Wow that is gonna be a LOT of brown paper, string and sealing wax !!

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clawson wrote:

barnacle wrote:
and a paraglider
Wow that is gonna be a LOT of brown paper, string and sealing wax !!

 

It's all right. I'm allowed to send it in for testing folded up. A box about 50x50x30cm, total weight about six kilos.

 

Neil

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I have some little bearings left over from a previous 3d printing project that I figured I'd use on the weather vane and the anemometer. They fit m3 screws, so I decided to order some 3mm shaft. All I got was an empty envelope with a rip where they had escaped. Second try got me some nice 3mm shafts, 300mm long. Hmm. These don't fit through my bearings. Rats, battery dead in my good caliper. Cheap caliper says 3.0 mm.

 

 

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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These don't fit through my bearings.

Unless way off, might make a nice press fit (don't damage or distort the races).  Heat the bearing in a toaster oven.  Then you'll need a good shaft puller later.

When in the dark remember-the future looks brighter than ever.   I look forward to being able to predict the future!

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avrcandies wrote:

These don't fit through my bearings.

Unless way off, might make a nice press fit (don't damage or distort the races).  Heat the bearing in a toaster oven.  Then you'll need a good shaft puller later.

 

That sounds reasonable, but I'll have to wait till later in the project to try it.

If you don't know my whole story, keep your mouth shut.

If you know my whole story, you're an accomplice. Keep your mouth shut. 

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Torby wrote:
I have some little bearings left over from a previous 3d printing project that I figured I'd use on the weather vane and the anemometer.

 

Outdoor need special plastics in printing 3D.

www.tokopedia.com/madagang .Buy and Donated cheap electronics and manuscripts.