We are off today so ask me tomorrow when I’m in the shop I know that it’s really popular and we’re selling them as fast as we can have them built. But if you do get one I’ll make sure you get one quick
If all capability s are correct a very fair Price 
Can you explain what a nitrogen sweep does?
I am going to try to use an ESP32 to read the 901P.
The ESP32 is arduino compatible, and is WiFi and Bluetooth capable.
The developer board i am using has a display, and is only $13 shipped from China.
I ordered one from amazon for $20 so it will be here tomorrow.
Oh, also need a logic converter as the ESP32 is 3.3v, and the 901p is 5v. I grabbed 10 for $10.
Cylewet 10Pcs 2 Channel Logic Level Converter 3.3V to 5V TTL Module for Arduino (Pack of 10) CYT1070 Amazon.com
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Lmk how that goes buddy
I’m super interested in this project. I’d like a few sensors for my Chinese 6" wiped films that only came with 1 sensor between cold trap and vac. I want a couple more on each on a tablet or phone
I got it working on the computer pretty well, but had a hard time with the raspberry pi.
If u have all the wires and whatnot, it takes less than 10 minutes to get it working on the PC.
Thanks to @gonzo script!
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What do you want to know.
So I’ve been away for a while and noticed a lot of activity on the thread but it seems like a lot of it is unrelated to the pirani vacuum sensor. If you want to have private discussions you should use the pm feature. The 901p is quite competitive and has real statistics posted on the accuracy in the manual along with a lot of related graphs and data. It truly is a 900$ sensor that happens to be available for 50$ because of some happenstance. Being able to read it with a regular computer instead of a specialized 1000$+ controller (glorified calculator) is just icing on the cake.
On a related note, if anybody is actually using the Script Commander I did have to change the script to stop saving the values because the user interface runs out of memory after about 5 minutes when continuing to place values in the table. Since I didn’t use the data in the table I just commented out the line that adds it. I also increased the font size for across the room readability.
I wired mine up with a VGA cable and a gender changer so that it was ‘plug and play.’ It was great to see the difference in vacuum between having 4 glass connections and having just 1 glass connection. Seeing the vacuum difference at varying points on my valve, or knowing that I adjusted it to 400mbar vs 500 mbar where on my analog gauge I really was in the dark. If there is ever a leak I know about it. When I did up the exhaust on my vacuum pump I wondered if the 1/2" tube would be enough and it was easy to run the pump w/o exhaust and with to see that I certainly needed a bigger exhaust. Hooking it up with 2" PVC maximizes the performance I get from my vacuum pump.
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You guys realize you can’t just wire up and use basic programing for vacuum sensors. You need to hook them up on a nist avs certified test bench and calibrate to the certified guage. Or else there’s no way to ensure your programing is even Correct.
Wirh what you are doing I’ve seen people read 90 microns when they were trully at 5, I’ve seen people run 0 microns when they were at 130 in reality. None of those guage heads are even remotely accurate out of the box. In fact they are very off. You should actually do the work to program it - then calibrate it to a known standard. Then program in the jump rate between software and leaking. Then you’ll have a clean guage
The programming is in the sensor the ‘programming’ script I wrote just talks to the sensor. The sensor includes zeroing and auto adjust procedures and comes factory calibrated (for the original intended use).
It is accurate out of the box so to speak. I did find mine to give more expected readings after running the calibration procedure. To be honest the repeat-ability is more important to most users who are trying to fine tune or repeat a process. I still don’t see how you come in here and crap on a 50$ solution while you sell $2500 solutions…
Here are the specs for this sensor, from the incredibly detailed manual, I’m curious as to how much better yours are…
Measuring range (N2 and Air): 1×10-5 to 1500 Torr
MicroPirani
Accuracy (1) (N2) 5×10-4 to 1x10-3 Torr: ±10% of reading
1×10-3 to 100 Torr: ± 5% of reading
100 Torr to Atm.: ± 25% of reading
Repeatability (1) (N2): 1×10-3 to 100 Torr: ± 2% of reading
Piezo Differential
Accuracy Piezo (1) -10 to +10 Torr: ±10% of reading + ±5×10-1 Torr
-100 to -10 Torr: ± 8% of reading
-760 to -100 Torr: ± 1% of reading
+10 to +100Torr: ± 5% of reading
Repeatability (1) (N2): -760 to +10 Torr ± 1% of reading
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Funny how I did just that, “wired it up and used basic coding” and it is hitting the same number as my bullseye. Yes I know the bullseye isnt as accurate as your extra special ones, but for our purposes this works just fine. In fact I bought 3 of them, all showed the same micron as the bullseye when hooked up together. (I got three thinking one was gonna be shit, but all worked well, I got them to record my diffusion pump readings)
We are buying used gear, we know they aren’t gonna be the best, however, it works with simple coding and u cant really say much against that
I’m with @gonzo
" I still don’t see how you come in here and crap on a 50$ solution while you sell $2500 solutions"
You are just trying to jump into each thread showing how smart you are, we get it, your smart dude.
Oh and thanks for the script! Saved me hours and got me a working product right out of the box, after u did the simple wiring of course. I also took out the logging, and just have it displaying the current value with only 5 of the last values (those are saved every minute) so it gives u an idea if the vacuum is headed up or down in the moment. I’m going to throw in a max and min recorded value soon, and just have it start running like an hour into its sequence
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Got mine working. Thanks for the script.
I made a simple serial to Bluetooth adapter so the sensor doesn’t need to be directly connected to the pc, and also display info locally at the sensor.
I also made sensor data available over WiFi. JSON so it can be read easily by other scripts.
Coding is still really rough. Mostly just copied from other places.
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sweet
I fixed the script so that it no longer crashes after 5 minutes or so and increased the font size. This fix disables the values being added to the table… Here is the link, the site doesn’t seem to let me edit the initial post with the new link and I no longer have a bookmark to the tinyhost master page 
http://s000.tinyupload.com/?file_id=04310556768978991663
If there are more people using it I don’t mind making more changes to it as I use it. Without storing values or updating the graph it ran rock solid for 2 days straight which is more what I’m after. Storing the data seemed cool but then wtf do you do with it, right? I’m running on a 20 yr old laptop that’s barely ticking.
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the stored data and time stamp may very well lead you to what went wrong when it does lol
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but either way im super stoked thanks so much for all you work man.
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Hey guys.
Wondering if you might be able to lend me a hand.
I got everything connected. Script communicated says im connected to my usb serial adapter. Worker script is loaded and launched.
But when the script window pops in the exact response text area it says “Text Label” instead of showing the equation as it does on your examples.
Im not sure if its simply a problem because im trying to run this all in Linux or not.
Any ideas you all might have, would be appreciated!