Temperature Sensor and a 3.5mm Jack

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alexander_hughes
 
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Temperature Sensor and a 3.5mm Jack

Post by alexander_hughes »

Lets start with...... I have a completely sealed off system due to High Vacuum(HV)... wiki it if you need.

I was told by my manufacturer(Brother) that he could possibly put in a jack such as a headphone jack.
My question is... Can I wire the AM2302 pins to a headphone jack to plug in on the inside of the chamber and on the outside run the normal 3 wires to their respectable pins on a Raspberry Pi?

I am not so electrically inclined but my programming skills for my project are adequate for other parts required of my project.

Is there a better Jack for this purpose?

In case you want to know... I have planned for wireless... (Problems I want to avoid... Outgassing and rupturing parts and batteries to a wireless system inside the chamber)
Which is one reason why I have decided to research (Pick your brains) on other forms of getting this sensor and any other sensors I need inside my high vacuum chamber without killing the bank.

Suggestions, comments, questions are VERY welcome.

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adafruit_support_mike
 
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Re: Temperature Sensor and a 3.5mm Jack

Post by adafruit_support_mike »

Those are called 'feedthrough connectors', and there are companies who specialize in feedthroughs for high vac applications. Hit the search engines with "high vacuum electrical feedthrough" for a list.

I'd say find a nearby college biology or physics department that works with high vacuum systems and see what they suggest. There's no substitute for talking to someone who knows the difference between, "yeah, that's easy" and "oh man.. don't even try". It's really hard to tell them apart from the outside.

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alexander_hughes
 
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Re: Temperature Sensor and a 3.5mm Jack

Post by alexander_hughes »

Thank you for a quick reply...

Yes, I did look at the feed through option, and it is exactly that... only for a hefty price tag of a couple hundred dollars or even as much as $700 for these feed troughs. They are made in varying sizes and their is a feed through option that would be perfect for what I need. Actually a little over engineered really as their feed throughs are for currents far beyond what is need for our project.
I don't want to seem like we are making our project on the cheap, but somethings don't need that much over engineering... or maybe they do.

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zener
 
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Re: Temperature Sensor and a 3.5mm Jack

Post by zener »

I took your question as more of an electrical question. I did not understand that you would want to use this connector as the feed through. But if you don't then what is the feed through you are using? My question is, will the AM2302 operate correctly in a high vacuum? I have no idea. I have never worked with that kind of environment. There is one way to find out of course... Anyway, I don't think anyone can speculate if a headphone jack can seal your container. If the manufacturer is suggesting this then maybe they have something special in mind that they have done before? As far as the signals themselves, they are digital, and not super high frequency, so generally those will go through connections well and would not be too picky about contact resistance. However, I would find the thickest gold plating I could just to be on the safe side.

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alexander_hughes
 
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Re: Temperature Sensor and a 3.5mm Jack

Post by alexander_hughes »

Thank you, that does make sense to use a high quality 3.5mm jack. Truly I am thinking he has something in mind for holding the pressure. As of last night, it isn't even the only idea he has had for giving me the power and comms inside the chamber.

The AM2302 operating in a high vacuum was a single part of the question, that if anyone already experienced using it in a high vacuum such as one of those projects where they send a gopro camera into high altitudes, but that was a long shot question.

I also do plan on throwing the necessary components in sort of one at a time to see what is going to die in a high vacuum.... maybe later I might offer throwing whole projects into it for others who need to test high or extreme high vacuums and extreme cold (<-20 degrees C.) on their projects... I think it would be fun. Sorry, I seem a little diabolical, atleast to the electronic components.

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adafruit_support_mike
 
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Re: Temperature Sensor and a 3.5mm Jack

Post by adafruit_support_mike »

Failures in pressure vessels (positive pressure or vacuum) turn parts into bullets, so the first goal is to make sure nothing comes loose.

In the absence of feed-throughs, I'd suggest running wires under the existing seals you'll have for a lid or an access panel. That already has to do the job of conforming to another surface and creating a suitable barrier.

I'd suggest using pieces of magnet wire instead of a cable though.. the insulation is baked on, so there's no space for an airflow path between wires, or between the wire and the insulation.

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alexander_hughes
 
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Re: Temperature Sensor and a 3.5mm Jack

Post by alexander_hughes »

All really helpful tips... thank you a lot. I did find an $80 feed through option which is about the cost of my wireless option... this may be exactly what I need since we were prepared to go with the wireless option.
In a couple weeks I hope to have the first up and running... expect some youtube videos or something whether it works or fails LOL.

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