Acurite 3N1TXCA1 Weather Station Teardown

Teardown of a decommissioned Acurite 3N1TXCA1 weather station. What kind of sensors and build quality do these inexpensive weather stations have?

The only two components of note are the outdoor temperature/humidity sensor and the pressure sensor (for barometric pressure readings). The most surprising thing is the piss-poor build quality of the unit.

SHT21 datasheet

DMP015A-1 datasheet

Similar (currently available) weather station

Disassembly/Inspection Of A Failed Cree LED Light Bulb

Disassembly/Inspection Of A Failed Cree LED Light Bulb
Very modular design. You could perform a non-destructive disassembly.

Disassembly/Inspection Of A Failed Cree LED Light Bulb

Disassembly/Inspection Of A Failed Cree LED Light Bulb
Yikes! Is that right? Turns out, it is.
Disassembly/Inspection Of A Failed Cree LED Light Bulb
This LED fell off during disassembly. They are not hard to get off but I wonder if this one was loose and could have been the cause/contributing to the issue the bulb was having.

Disassembly/Inspection Of A Failed Cree LED Light Bulb

Disassembly/Inspection Of A Failed Cree LED Light Bulb

Disassembly/Inspection Of A Failed Cree LED Light Bulb
Interestingly, no heat sink compound was used between the heat sink and the LED substrate.
Disassembly/Inspection Of A Failed Cree LED Light Bulb
This part was in the center of the heat sink. The bottom contacts made contact w/the driver board and the top contacts w/the LEDs.

Disassembly/Inspection Of A Failed Cree LED Light Bulb

Disassembly/Inspection Of A Failed Cree LED Light Bulb
Could the discoloration on the silk screen labeling be a sign the board was getting to hot?
Disassembly/Inspection Of A Failed Cree LED Light Bulb
Good quality, high temp rated CAPs
Disassembly/Inspection Of A Failed Cree LED Light Bulb
There was a lot more of these white cruddy spots on this inductor before this picture was taken… Not sure if this is an indication of an issue.
Disassembly/Inspection Of A Failed Cree LED Light Bulb
Some crud around the right lead of the primary capacitor. May just be left over from manufacturing. The cap looks fine, no bulging or signs of leaking.

Refrigerator Controller-Thermostat

A bit back I opened my office mini fridge and found that it was warm. I checked all the obvious things: it was plugged in and getting power, and the thermostat was set correctly. Deeper diagnostics revealed that the thermostat was faulty. No matter the thermostat setting, it was not engaging to cool the fridge. If I bypassed the thermostat and manually (i.e. shorted the compressor leads) started the compressor the fridge cooled as it should.

I was unable to find an OEM replacement thermostat but figured I could make a replacement for less than a new fridge would cost.

Refrigerator Controller - Thermostat

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Automatic Server Room Exhaust

The Problem

I have a home “server room” that houses a couple of servers and other network hardware. In fact this site is being served to you from a VM running on a server sitting in that room.

If you’ve spent any time around servers (or any electronics for that matter) you know that they generate heat. I’ve recently consolidated a couple of physical servers by virtualizing them but the remaining physical servers, switch, cable modem, and UPS still generate about 2000 BTUs of heat. That’s about the same heat output as a small space heater.

The “server room” is a repurposed 30sq foot bathroom that is off of a main room (think of the typical master bedroom/bathroom setup). Managing the heat produced by the equipment has been an issue mostly solved by keeping the server room door open (to keep heat from building up) and running the existing bathroom exhaust fan.

My main issue with the current setup is having to keep the server room door open. This is especially an issue in the summer because the heat produced from the equipment is enough to overwhelm any cool air being pushed into the main room from the central AC. This makes both the server room and the main room perpetually hot. Also annoying is the noise from the equipment, and having to keep the door open prevents me from being able to doing anything to reduce dust incursion into the server room.

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Random Thoughts on Drone Package Delivery

By now most people have seen or at least heard about Amazon’s Prime Air service. Supposedly, still in the R&D phase Amazon unveiled its drone delivery plans on 60 Minutes back in December. I heard many people dismiss Prime Air as a publicity stunt with no real chance of ever… ahem, getting off the ground. While I do think announcing it at this point is almost certainly a way to garner publicity, I don’t think that there is any reason it can’t be done.

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Mailbox Notifier

Note: since the original posting, I’ve added some updates (bottom of page).

A couple of years ago I came across some vintage light bulbs while perusing the aisles of Home Depot. Since then, I’ve been looking for a project to use them in. I thought that it would be cool to use one as an indicator light and started to form this picture in my head of what it would look like. I wasn’t sure what the bulb would be indicating, but the idea was now in my head and once I figured out what to use it for, I’d have to make it.

All that to say that this project was motivated by the need to make an indicator light using one of those vintage bulbs.

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