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Offline TheBushPilot

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Station Setup
« on: December 13, 2021, 12:16:31 PM »
Hi all, this was my weather station setup before I had it taken down due to personal matters. It went through several iterations while it was in service. I was looking through old files and found some pics and thought someone might be interested in them.

The mast was constructed using one inch galvanized steel pipe and fittings from the hardware store. Cabling was stock with the stations/sensors except for the Texas Electronics and R. M. Young anemometers, those used cat5 ethernet cable. While yes the cable itself might deteriorate over time due to UV breakdown, that was not a primary concern as I did not anticipate the cable moving at all once it was in place for a very long time.

Consumer grade stations:
Davis Instruments Weather Monitor II
Peet Bros Ultimeter 800

Commercially available Sensors:
R. M. Young 05305 AQ, 05103
Texas Electronics TV-114/TV-104-5D
APRS World 6500
Vaisala HMP35C
R. M. Young 61302L

Wind speed and direction were measured using a multitude of instruments. In the beginning a vintage Texas Electronics wind set were used along with Davis and Peet Bros stations and a random APRS cup set I had. Then removed the APRS and put the 05305 in place. At that time I had an R. M. Young 27600 display hooked up to the AQ. I must say that display was really nice despite its age and performed really well. Sold the 05305 and got a 05103, the same one used through the remainder of the mast's life. Experimented with a compact format for a while. Not exactly sure what I was trying to achieve in doing that, maybe just a proof of concept. Went back to the single tall mast design after acquiring another 05103. Ended up selling the Davis after some time and decommissioned the Peet Bros, then moved toward the final single pipe design that had more height. I went this route again to not only conserve weight but also significantly simplify the design. This also made it very easy for maintenance as the whole mast could pivot parallel to the edge of the roof.

For a brief period temperature/humidity was measured using an HMP35C. This was housed within a custom fan aspirated radiation shield I made but never truly finished, it was very experimental. Temperature was never quite accurate, though a multitude of factors probably contributed to this. The larger plate shield was a Davis 7714 which housed the temperature sensor for the Peet Bros station. I had plans to employ a 43408 FARS from Young with their 41382LC2 to measure T/RH at ground level over grass.

The rain gauge was from Peet Bros but really just a rebranded 8" one from RainWise. While it met the NWS spec the plastic within the cone was starting to deteriorate as it had been in use for several years prior, so observed measurements were probably suspect.

While pressure measurements were never made operational, a Nishiyama & Bedard quad plate pressure port was employed along with a 61302L. The port was 3D printed and later on I made a modified version similar to Paroscientific's Digiport, consisting of larger outer plates to further mitigate turbulence and pressure perturbation. During that time I also found that during the PAM II project, they utilized the QPPP. One of the scientists found extending the top of the tube it increased overall performance. The vinyl tubing from the pressure port to sensor was put through aluminum collars and zip tied to the mast to prevent any unwanted movement or compression of the hosing.

A Campbell Scientific CR10X logger was used within the house with future plans to mount a weather proof enclosure to the base of the pipe in the last image. That fell through as the whole thing was decommissioned but later on a CR300-WIFI was probably going to be used as the final data logger. Would have continuously logged second interval observations in an effort to make fine-scale data sets for my area and probably upload it to CWOP and wherever else.

The whole goal of this was to mimic an ASOS station or mesonet and have similar capabilities. Though of course, I'll be the first to admit accuracy is probably lacking given the inherent environment and siting requirements are abhorrent compared to real world stations. None of the instruments are calibrated, as I did not have the money/resources/desire to do so at the time as this was purely for personal gain and hobby enjoyment. Sensor placement is less than ideal than I would've liked but because I lived in a heavily suburban neighborhood, I did the best I could with the resources available.

Cheers,

Quinton

All 8 images are below, in order from oldest to newest.

(Took way longer than it should have for me trying to post the pics. But they're there now, finally.)
« Last Edit: December 13, 2021, 02:35:23 PM by TheBushPilot »
"There is ó always ó more than one thing influencing anything we are trying to measure." ~ Sherman Fredrickson
"Well right now I don't feel very damn researchy" ~ Tim Samaras
"Do it right or don't do it at all."

05103 (4), HMP35C (4), CR10X (2), 61302L (1), TV-114 (1), TD-104-5D (1)
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Offline TheBushPilot

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Re: Station Setup
« Reply #1 on: December 13, 2021, 02:07:43 PM »
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« Last Edit: December 13, 2021, 02:12:40 PM by TheBushPilot »
"There is ó always ó more than one thing influencing anything we are trying to measure." ~ Sherman Fredrickson
"Well right now I don't feel very damn researchy" ~ Tim Samaras
"Do it right or don't do it at all."

05103 (4), HMP35C (4), CR10X (2), 61302L (1), TV-114 (1), TD-104-5D (1)
LOGGERNET, GR2Analyst

Offline TheBushPilot

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Re: Station Setup
« Reply #2 on: December 13, 2021, 02:10:03 PM »
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"There is ó always ó more than one thing influencing anything we are trying to measure." ~ Sherman Fredrickson
"Well right now I don't feel very damn researchy" ~ Tim Samaras
"Do it right or don't do it at all."

05103 (4), HMP35C (4), CR10X (2), 61302L (1), TV-114 (1), TD-104-5D (1)
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Offline blizzardof78

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Re: Station Setup
« Reply #3 on: December 29, 2021, 02:33:27 PM »
What do you have as far as indoor display units for the TE and the Peet?

Offline TheBushPilot

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Re: Station Setup
« Reply #4 on: December 29, 2021, 08:02:15 PM »
The Texas Electronics station used old analog panel meter displays, one for wind speed and the other for direction. They hooked up to an enclosure that had signal conditioning PCBs. The panels themselves are in storage at this time. When I get the chance I will have to find them and send pictures. The Peet Bros station used the standard 800 style display. I did however modify their forty-something foot 10 conductor data cable to carry power from the inside of my house to the junction box. This was because there was not a clean way to hide the power with the large wall adapter included. Standard 8 conductor cat5 cable with the RJ45 connector was used on either ends while the two extra leads were power. Ideally, I would have had power where the junction box was located but the way I set it up worked fine and was convenient. Given the power requirements for the station were not too ridiculous, there wasn't much need to worry.

Cheers
"There is ó always ó more than one thing influencing anything we are trying to measure." ~ Sherman Fredrickson
"Well right now I don't feel very damn researchy" ~ Tim Samaras
"Do it right or don't do it at all."

05103 (4), HMP35C (4), CR10X (2), 61302L (1), TV-114 (1), TD-104-5D (1)
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Offline CW7491

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Re: Station Setup
« Reply #5 on: December 29, 2021, 08:24:57 PM »
Iím interested in your custom FARS. How did it work for you? Iíve been in the process of building and starting to test my own stealing concepts from the ASOS HO-1088, Met One 076b and Davis. Part of it is just the enjoyment of building it and seeing if I can get improved performance, but I was also trying to design a more compact size shield than the Davis

Offline TheBushPilot

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Re: Station Setup
« Reply #6 on: December 30, 2021, 01:27:09 PM »
Here's a crude drawing of my design.

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It's built like your typical two walled fan aspirated radiation shield. 3" outer and 1 1/2" inner diameter schedule 40 PVC pipe. I had to modify the lower coupling adapter so the inner tube could go through it and attach to the top coupling. The fan in the shield was far too weak for the demand, I made the mistake of using one of those smaller low profile fans as that was all I had lying around at the time. If I revisit this in the future that's definitely something I will make sure is done right.

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The vent holes for the outer intake were sized such that the aspiration rate of the outer tube was slower than the inner one. In theory this would keep the inner tube decoupled from not only the solar radiation of the ambient environment but also the air within the shield itself. Further testing is needed to determine the optimal hole size as well as how many holes are needed but what I had worked well enough at the time.

Generally speaking, I tried to keep the design relatively simple, with no real objective to have it resemble any one FARS.

As for performance, I unfortunately cannot give you a straight answer. There are too many variables to give a definitive result. For the short time the station was recording T/RH the wire outlet was not sealed and I hadn't put forethought into coating the shield with reflective white paint. All relatively simple things that could have probably increased accuracy significantly. Siting of the FARS was also problematic as it was located on top of my roof. I have no doubt the airmass measured was modified from the surrounding surfaces increasing temperatures drastically. During the summer when temps would reach the high 80's but never quite make it to 90 my station would sometimes be on target and other times be a few degrees above sometimes upward of 5 deg. Notably though in times of low solar radiation and rain, temperatures matched the surrounding airport ASOS station obs by +/- 2 Deg F. This leaves me to believe the shield itself performs acceptably but every other factor trumps its potential. Of course it should be noted the sensor was not calibrated and had not been for many years. From what I understand it was old stock from a USGS site after they went through and updated their network. Comparing it to the Peet station I had, temperature was close enough for my purposes. But of course, a big asterisk should be placed on the measurements given all of the uncertainty.

I will probably revisit this project in the future when I am able and finish the design I had started. Will also use up-to-date calibrated instruments and have reference shields with appropriate siting to determine accuracy.

Cheers
"There is ó always ó more than one thing influencing anything we are trying to measure." ~ Sherman Fredrickson
"Well right now I don't feel very damn researchy" ~ Tim Samaras
"Do it right or don't do it at all."

05103 (4), HMP35C (4), CR10X (2), 61302L (1), TV-114 (1), TD-104-5D (1)
LOGGERNET, GR2Analyst

Offline CW7491

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Re: Station Setup
« Reply #7 on: December 30, 2021, 04:02:20 PM »
Thanks for sharing and for the detailed info. Those are nice drawings! Itís always interesting to me how people come up with different ways to achieve the same end. It provides ideas of how to improve your own design. Thank you.

I have a similar design. I have a double wall version and a triple wall version. Not sure the triple wall is necessary, but will hopefully be able to test soon as we come into the warmer months.

Offline TheBushPilot

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Re: Station Setup
« Reply #8 on: December 31, 2021, 09:53:10 AM »
I absolutely 100% agree. A good portion of information on those FARS I gathered was actually from this site long ago but hadnít put it to use up until recently. Funny how life works that way, things come full circle.

You have me intrigued with your designs and I would be very curious to see them. I wouldnít necessarily say triple walls are unnecessary. Itís all about use case and execution. The R. M. Young 43408s are double walled while their newer 43502 shield is triple walled. Both shields claim to mitigate error to 0.2C. Despite having different designs they both achieved the same accuracy. Or say the met one 076B, that has errors of around 0.02C and itís double walled. Iíd like to believe the number is irrelevant so long as itís designed well.

Of course there are a whole slew of other factors that play into the accuracy of FARS. But getting the main ones down youíre pretty much covered. And donít even get me started on mobile platforms, thatís a whole other discussion, lol.

Cheers
"There is ó always ó more than one thing influencing anything we are trying to measure." ~ Sherman Fredrickson
"Well right now I don't feel very damn researchy" ~ Tim Samaras
"Do it right or don't do it at all."

05103 (4), HMP35C (4), CR10X (2), 61302L (1), TV-114 (1), TD-104-5D (1)
LOGGERNET, GR2Analyst

Offline CW7491

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Re: Station Setup
« Reply #9 on: December 31, 2021, 07:56:55 PM »
I donít have any great drawings like you do, but when I get a chance, Iíll share some pictures

Offline Bashy

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Re: Station Setup
« Reply #10 on: December 31, 2021, 09:52:13 PM »
I made something similar for my old OS temp/hum sensor, i didn't have the thin section near the top though and i filled the gap between the inner and outer tubes with expanding insulation foam, that was messy but its been running now for about 4 years, can be seen here if you're interested, it is fairly crude but it serves a purpose, it does read up to +2ļC higher than the Davis in the sun but that's hard to tell if that's the sensor itself or the shield, during the night its pretty much spot on with the Davis so it's probably the shield, be it the fan or the actual heat from the shield itself, i would be surprised though what with all that insulation.
« Last Edit: December 31, 2021, 10:04:46 PM by Bashy »
Kind regards
Bashy

Offline mcrossley

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Re: Station Setup
« Reply #11 on: January 01, 2022, 07:00:15 AM »
A man with an anemometer knows what the wind speed is, a man with many....  :lol: =D>
Mark

Offline TheBushPilot

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Re: Station Setup
« Reply #12 on: January 03, 2022, 10:40:11 AM »
I donít have any great drawings like you do, but when I get a chance, Iíll share some pictures

They aren't anything spectacular, just doodles in mspaint, but I appreciate the kind words. :grin: And yes, I look forward to those. You've piqued my curiosity.

I made something similar for my old OS temp/hum sensor, i didn't have the thin section near the top though and i filled the gap between the inner and outer tubes with expanding insulation foam, that was messy but its been running now for about 4 years, can be seen here if you're interested, it is fairly crude but it serves a purpose, it does read up to +2ļC higher than the Davis in the sun but that's hard to tell if that's the sensor itself or the shield, during the night its pretty much spot on with the Davis so it's probably the shield, be it the fan or the actual heat from the shield itself, i would be surprised though what with all that insulation.

I do quite like that design, its simple and gets the point across. Reminds me of an Apogee Instruments TS-100. You mention inaccuracies of the shield during the day that then resolve at night. One thing that immediately stood out to me after you mentioning this was the off-white color of the plastic on your FARS. Though with the housing filled with insulation that shouldn't be an issue, right? The air being ingested through the bottom is not modified by the shield either. Unless I'm underestimating the effect of such a little color difference you've got me stumped on that one. Maybe the surrounding airmass is being modified? What does the siting of your Davis T/RH sensor look like?

A man with an anemometer knows what the wind speed is, a man with many....  :lol: =D>

Funny you say that. I actually went back to a singular anemometer after asking myself, "Do I really need all of these sensors?" I love the novelty of having a whole mast of instruments but practicality was more appealing. Not only this but I had to indefinitely borrow the second wind monitor for a mobile mesonet at the time, but that's a whole separate thread.

Cheers
"There is ó always ó more than one thing influencing anything we are trying to measure." ~ Sherman Fredrickson
"Well right now I don't feel very damn researchy" ~ Tim Samaras
"Do it right or don't do it at all."

05103 (4), HMP35C (4), CR10X (2), 61302L (1), TV-114 (1), TD-104-5D (1)
LOGGERNET, GR2Analyst

Offline Bashy

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Re: Station Setup
« Reply #13 on: January 03, 2022, 10:49:00 PM »

I made something similar for my old OS temp/hum sensor, i didn't have the thin section near the top though and i filled the gap between the inner and outer tubes with expanding insulation foam, that was messy but its been running now for about 4 years, can be seen here if you're interested, it is fairly crude but it serves a purpose, it does read up to +2ļC higher than the Davis in the sun but that's hard to tell if that's the sensor itself or the shield, during the night its pretty much spot on with the Davis so it's probably the shield, be it the fan or the actual heat from the shield itself, i would be surprised though what with all that insulation.

I do quite like that design, its simple and gets the point across. Reminds me of an Apogee Instruments TS-100. You mention inaccuracies of the shield during the day that then resolve at night. One thing that immediately stood out to me after you mentioning this was the off-white color of the plastic on your FARS. Though with the housing filled with insulation that shouldn't be an issue, right? The air being ingested through the bottom is not modified by the shield either. Unless I'm underestimating the effect of such a little color difference you've got me stumped on that one. Maybe the surrounding airmass is being modified? What does the siting of your Davis T/RH sensor look like?

Cheers

Actually, yes, i believe it was the Apogee i tried to copy and failed but its been up nearly 4 years
I later painted it gloss white, if anything the davis shield is more off colour as its needs a clean, I kept putting it off last year lol...

here's the siting of the davis shield on the mast, i had to do it that high to mitigate and radiant heat from the summerhouse roof.
https://youtu.be/iIr9kUz-oJU

Perhaps the higher temps from the OS is due to being close to the corner with 2 sides being 6ft fencing and its holding the temps there, just a guess lol
« Last Edit: January 03, 2022, 10:55:49 PM by Bashy »
Kind regards
Bashy

Offline TheBushPilot

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Re: Station Setup
« Reply #14 on: January 04, 2022, 10:41:13 AM »
Actually, yes, i believe it was the Apogee i tried to copy and failed but its been up nearly 4 years
I later painted it gloss white, if anything the davis shield is more off colour as its needs a clean, I kept putting it off last year lol...

here's the siting of the davis shield on the mast, i had to do it that high to mitigate and radiant heat from the summerhouse roof.
https://youtu.be/iIr9kUz-oJU

Perhaps the higher temps from the OS is due to being close to the corner with 2 sides being 6ft fencing and its holding the temps there, just a guess lol

Pshh I don't think you failed. You wanted to make a FARS and you did, I'd say that's a success. Aside from this it's clearly stood the test of time.

You're lucky to have a mast that tall in your backyard, I'm currently living in an apartment and no such things are tolerated here. :roll:

As far as inaccuracies go, the thermal mass of the shield itself might contribute to temperature error. I have no way of testing that however. What might be happening is the insulation becomes heat saturated (if that's even a term) and significantly reducing the efficacy of the shield because it's no longer providing a means to decouple the thermal energy from the environment. Obviously direct solar radiation isn't an issue as the sensor is clearly covered and reradiated energy isn't either as there are no reflective surfaces and grass below the shield. Perhaps like you've said the latent heat from the surrounding area could be causing errors. Another possibility is that both the Davis and OS T/RH sensors are fine, it is simply the difference in height creating such errors. It's surprising how much a difference a few meters makes when doing temperature observations. Like Sherman Fredrickson of the NSSL always said: "There is always more than one thing influencing anything we are trying to measure." Who knows? All ideas, and I could very well be wrong and am by no means an engineer so take what I say with a grain of salt.

Again, who knows, maybe the cause is something far simpler than originally anticipated.

Anyway, I hope my ramblings gave you something to go off of.

Cheers
"There is ó always ó more than one thing influencing anything we are trying to measure." ~ Sherman Fredrickson
"Well right now I don't feel very damn researchy" ~ Tim Samaras
"Do it right or don't do it at all."

05103 (4), HMP35C (4), CR10X (2), 61302L (1), TV-114 (1), TD-104-5D (1)
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Offline CW7491

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Re: Station Setup
« Reply #15 on: January 04, 2022, 11:10:08 AM »
Was able to get some pictures to share. The exterior of the shield looks most like ASOS, but I stole ideas from the Met One 076b for the interior, using a triple wall and a vented cap at the sensor intake. I donít like how the ASOS shield has only a single tube that is open at the bottom. Everything I used is available at Loweís/Home Depot here in the US with the exception of the interior aluminum tubing. I also have just a double wall design using only PVC and everything can be sourced at those stores.

The biggest problem I struggled with was how to protect the sensor from reflected radiation from the ground while still getting it sufficient airflow. I ended making an offset double louvered vent cap that I think will work well. The other potential issue is Iím not sure if the deflection skirt is enough to ensure exhaust air is not drawn back into the intake. It also needs a coat of paint Ö

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« Last Edit: January 04, 2022, 11:22:42 AM by CW7491 »

Offline TheBushPilot

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Re: Station Setup
« Reply #16 on: January 04, 2022, 09:06:23 PM »
Was able to get some pictures to share. The exterior of the shield looks most like ASOS, but I stole ideas from the Met One 076b for the interior, using a triple wall and a vented cap at the sensor intake. I donít like how the ASOS shield has only a single tube that is open at the bottom. Everything I used is available at Loweís/Home Depot here in the US with the exception of the interior aluminum tubing. I also have just a double wall design using only PVC and everything can be sourced at those stores.

The biggest problem I struggled with was how to protect the sensor from reflected radiation from the ground while still getting it sufficient airflow. I ended making an offset double louvered vent cap that I think will work well. The other potential issue is Iím not sure if the deflection skirt is enough to ensure exhaust air is not drawn back into the intake. It also needs a coat of paint Ö

Wow, I really like that design, it's pretty ingenious if you ask me. I wouldn't have ever thought to use those commercially available vent caps with the screws already in them. And yes my memory was wrong and like you said the 076B has 3 walls. While I was at a camp a few years ago I got to check out the Kentucky Mesonet facility and had a chance to look at those shields personally. The things are huuge. I remember the intake having a flat plate with six holes spaced such that three were on either side. Below is a rough idea of it from what I remember. It was a little off-putting as I would have thought you'd want an open intake for maximum aspiration but I suppose the holes are big enough that sufficient flow happens. Again I can't exactly remember if the second tube or third innermost had the plate but hopefully what I have gets the point across.

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Schematic of the actual shield from Met One

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I don't see why the vent type cover wouldn't work. Should block most incoming re-directed radiation.

The other potential issue is Iím not sure if the deflection skirt is enough to ensure exhaust air is not drawn back into the intake.

There might be an issue depending on how powerful of a fan you have in there. If it's outputting quite a bit of flow then you might have issues on calm days. But again, I'm not an engineer. It would probably take trial and error to figure that out. I like your take of the HO-1088 with the deflector plate. Though my design didn't have a deflector (which I will probably add in the next rendition), I made sure there would be no way modified air could get ingested again. Should probably consider putting an intake shield plate in there as well.

I know you said you wanted to test accuracy during the warmer months but day to day have you been able to roughly determine how well it performs?
"There is ó always ó more than one thing influencing anything we are trying to measure." ~ Sherman Fredrickson
"Well right now I don't feel very damn researchy" ~ Tim Samaras
"Do it right or don't do it at all."

05103 (4), HMP35C (4), CR10X (2), 61302L (1), TV-114 (1), TD-104-5D (1)
LOGGERNET, GR2Analyst

Offline CW7491

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Re: Station Setup
« Reply #17 on: January 04, 2022, 10:07:45 PM »
Thanks and thatís a great memory! I have a USCRN site not to far away and I was able to ride down there and look at the shields and take some pictures. I was also surprised how big they are and how restrictive the two plates over the sensor intake port seem to be. But the 076b is as close to a gold standard as there is and the Davis FARS also is designed to block reflected radiation from the ground, snow, etc as well.

The limited testing Iíve done with my homemade shield is very promising. Unfortunately I donít have a great setup currently to set up a good longer term test. I hope to take the shield and the Davis shield down to the USCRN site and get some side by side results. Iíve designed my shield specifically to accommodate the Davis temperature and relative humidity sensor board. The overall height is about the same as the Davis shield, but itís overall smaller. Finally, if the deflection skirt isnít adequate, Iíll probably just try to move it up higher on the shield.

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« Last Edit: January 04, 2022, 10:27:20 PM by CW7491 »

Offline TheBushPilot

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Re: Station Setup
« Reply #18 on: January 05, 2022, 10:35:36 AM »
Thanks and thatís a great memory! I have a USCRN site not to far away and I was able to ride down there and look at the shields and take some pictures. I was also surprised how big they are and how restrictive the two plates over the sensor intake port seem to be. But the 076b is as close to a gold standard as there is and the Davis FARS also is designed to block reflected radiation from the ground, snow, etc as well.

The limited testing Iíve done with my homemade shield is very promising. Unfortunately I donít have a great setup currently to set up a good longer term test. I hope to take the shield and the Davis shield down to the USCRN site and get some side by side results. Iíve designed my shield specifically to accommodate the Davis temperature and relative humidity sensor board. The overall height is about the same as the Davis shield, but itís overall smaller. Finally, if the deflection skirt isnít adequate, Iíll probably just try to move it up higher on the shield.

Interesting. Very very interesting. Now seeing the bottom of that shield I have even more questions LOL. Of course it's far more complex than I originally remembered. With an error of like what, 0.02 Deg C I'd say whatever Met One is doing they are doing really well. Guess I'll just have to try and replicate that to the best of my abilities on the next go. This thread has got me reconsidering my choice of FARS for my future AWS project. Seems like a commonly neglected aspect of these shields is the reflected re-radiation from the ground. Perhaps why many commonly accepted shields made by reputable instrument manufacturers can't get any more accurate is because of the open intake design. No number of tube layers will save you from the stuff coming in from the bottom up.

I look forward to those numbers. I'd think it's a bit inconveniencing to try and house such an awkwardly shaped sensor in a tube like you have. Though it couldn't be any worse than trying to shove a larger form factor HMP style probe into anything right? Taking the shields to an official site is a really good idea, I wouldn't have ever thought to do that. I will have to do the same when the time comes. And yes, the beauty of these things is there is no right answer, total customization is possible. Which is probably a good contributor to why it's so appealing to make your own housings and such.

Cheers
"There is ó always ó more than one thing influencing anything we are trying to measure." ~ Sherman Fredrickson
"Well right now I don't feel very damn researchy" ~ Tim Samaras
"Do it right or don't do it at all."

05103 (4), HMP35C (4), CR10X (2), 61302L (1), TV-114 (1), TD-104-5D (1)
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Offline CW7491

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Re: Station Setup
« Reply #19 on: January 05, 2022, 01:27:52 PM »
Yes, with 2Ē PVC, you have to cut down the Davis sensor for it to fit, but itís not much of a trim. I was able to find 2.25Ē outside diameter aluminum tubing with a 0.065Ē wall that works perfectly from onlinemetals.com. They will also custom cut whatever length you need Ö

Offline TheBushPilot

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  • Posts: 46
  • Storm chaser and independent researcher
Re: Station Setup
« Reply #20 on: January 05, 2022, 03:01:46 PM »
Nice nice, I bought loads of aluminum tubing for mesonet racks and couldn't remember where I got it so I had to look. Turned out it was Midwest Steel Supply but I'll certainly keep that site in mind in the future as well. I wanted to use R. M. Young T/RH probes but it's gonna be a logistical nightmare trying to fit such a huge housing inside a tube like that. Was anticipating on using 43408s but am questioning that decision now. I guess I'll just have to determine how accurate I want my readings to be with respect to the sensor itself. :-?
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