Tag: Electronics

Chicken Cam: Incubator Edition

March 4, 2018 » Geek, Life

It’s been over a year since we’ve had chickens and we’ve missed them, so this Christmas we got Lizzy and Charlotte an incubator so that we could try hatching some this spring.

When we went to purchase eggs, we found that you could most easily get them 10 at a time from the hatchery we have used in the past, Murray McMurray. Since the incubator we got the girls could only hold seven, we would need something for the other three. Some searching found that you could use a styrofoam cooler and a lamp to create a makeshift incubator, so I planned on that.

Once I had a plan to create an incubator, I knew I would have to overcomplicate things. Four years ago I built a webcam for our chicks so I figured I would do that this time too. Also, just setting a lamp and thermometer in and hoping for the best seemed like a potential waste of good eggs, so I wanted to monitor the temperature and humidity, and regulate them.

My initial design was a Raspberry Pi connected to a cheap DHT11 temperature and humidity sensor, controlling a relay that could turn the light on and off. All of it would be hooked up through a PID controller to keep the temperatures right where we want them. Eventually, I added a thermocouple with a MAX6675 for more accurate temperature readings.

Raspberry Pi, Relay and a mess of wires.

The server side would be designed similarly to the previous chicken cam, except written in Go. The stats would be tracked in InfluxDB and Grafana would be used for viewing them.

After I got all the parts I did a little testing, then soldered things up and tested it to see how it ran.

Initially I wrote everything in Go, but the DHT11 reading was very spotty. Sometimes it would respond once every few seconds, and sometimes it would go a minute or more failing to read. I wired on a second DHT11 and tried reading from both, but I didn’t get that much better performance.

Eventually I tried them from the Adafruit Python library and had much better luck, so I decided to just read those from Python and send them to my main Go application for consumption. I still have trouble with the DHT11’s, but I suspect it’s my fault more than the sensors fault.

My next issue was that it was extremely jittery, the readings would vary by degrees one second to another, so I collected readings in batches of 5 seconds then averaged them. That smoothed it out enough that graphs looked reasonable.

On. Off. On. Off. On. Off.

Temperature was now well regulated, but the air wasn’t humid enough. I switched to a sponge and found I could manage it much easier that way. I briefly tried a 40W bulb thinking I could spend more time with the lamp off, but temperatures still plunged at the same rate when the light was off, so I mostly just created quicker cycles.

After putting the 25W bulb back in, I still wanted a longer, smoother cycle, so I wrapped up a brick (for cleanliness) and stuck that in there. That got me longer cycles with better recovery at the bottom, it didn’t get too cold before the lamp came back on. Some slight improvements to the seal of my lid helped as well. I had trouble with condensation and too much humidity, but some vent holes and better water management took care of that.

Before the brick.

After the brick.

For the server side, I mostly duplicated the code from the previous Chicken cam, but in Go. Then I used the InfluxDB library to get the most recent temperature and humidity readings for display.

At this point, I felt ready for the eggs, which was good because they had arrived! We placed them in the incubator and we’re just waiting now. On day 8 we candled them with a homebuilt lamp i.e. a cardboard box with a hole cut in it.


Things seem to be progressing well so far, so here’s hoping something hatches!

DK421 Hardware

November 5, 2006 » Geek

This afternoon I was without anything to do when I remembered my DK421 project, which had been shoved off into a dusty corner of my hard drive. I didn’t feel like programming any, and wouldn’t know what to do or add anyway, so I got into the hardware side of it.

The Sheets

I dug into Stephanies old room and found the keyboard from the green dinosaur, an Acer computer from the early-90’s. Anyway, I found it, took it to my room and cracked it open. Very simple device really. The keypresses are captured by switches composed of two sheets of plastic, very similar to slide-projector transparency sheets, with tracing on them. When you press the key it compresses a rubber bubble in a sheet and smashes the air, and thus the switch, down and completes the circuit. These connections go to a board with some leds and a chip for translating them into whatever goes down that PS2 cable.

I imagine that a newer keyboard might be more complicated, at least if it’s usb. Maybe not though. I only have so many keyboards to rip open.

Following the tearing apart of the keyboard I hooked it up to my old gateway laptop (it’s the computer I care the least about) and fired it up. No lights, no response. I shut it back down and figured out that I hadn’t reconnected a little black ground that had been hooked onto the metal mounting board as well as one of the pins. If you look at the picture of the transparency-stuff circuit you can see that one pin is connected only to a big spot for the ground.

The Pins

I taped it up and got it working right off the bat. Shiny. I then taped it onto the laptop in the lovely testing position illustrated here. I got a piece of thick copper wire, off of an old power supply, and generously stripped the ends (okay, my father did for me), 1.5″ at least, then coiled each end around a long finishing nail (that’s what it said on the box) and taped it up. This made for a nice, easy to control point-to-point connector for me.

With my newly created tool I fired up VIM and started shorting the pins together to see what they wrote. Okay, thats not true. First I tried tracing individual keys on the transparent stuff, but that got old real fast. It is, however, necessary for finding keys like shift. Regardless, I tried out the good old hunt and peck method, and soon had a list with more than enough keys for the drum triggers. I then tried out the shift key with a piece of spare wire, it works great. Thats an important one, because it is needed for the high-hat pedal.

The Shift Key

Well, thats enough for now. Hopefully the pictures shed some light on the matter if it’s still fuzzy. I haven’t made up my mind on what to build the triggers out of. I almost want to go the air pressure route so the switches won’t wear out to fast. I’ll also have to consider how to build and mount all this, I’m thinking PVC at this point. Off to a good start though :)

Additional Photos

Chu Moy Part Deux

October 14, 2006 » Geek

You thought I forgot about my chu-moy amplifier didn’t you? You thought it was lost to the depths of the boxes of parts and broken, half-made things in my room. You thought wrong. I recently aquired a highly rare container known as an “Altoids tin” and did the test fit of the pieces this evening.

If you ever want to put something in an altoids tin, measure it first. I had to hack away parts of my c-board to get it in. Also, poking holes and reaming them out with a knife and screwdriver aren’t the optimal hole making solutions, but they do work. It’s a tight squeeze, but everything fits and it’s lined in electrical tape for the circuits comfort. Still not sure where the power switch will go. I guess that can wait until I actually buy or scavenge a switch.

Open Closed
Update (10/14/2006)
I Found a switch while I was cleaning up my room. It’s from a busted computer PSU. Not going to fit in the case though, I think it will just live on the board.

Playstation 2 Mod

October 4, 2006 » Geek

I recieved my DMS4 S.E. Lite mod chip today. I had used Swap Magic 3.5 for a while with a flip-top, but it was noisy and my failure rate was kinda high. Anyway, I figured it couldn’t be too hard to put on a chip and solder a couple leads, right?

So I broke out the tools and got to work. First thing to say, documentation is near non-existant. I scraped together enough info to understand the wiring diagrams, but it’s a bit tough. Second thing to say, some of these leads are absolutely tiny. Here’s a picture of one of the BIOS chip leads with a guitar pick for scale, and a shot of the first four connections. Click for a bigger view.

Tiny IC Pins The First Four Wires

Those IC’s are tiny little buggers. Anyway, I got the majority of the wires hooked up and solid in a few hours time. I have six left. Five are just some easy flat pins that I need to scrape the finish off so my solder will stick. I found that out in a forum after about 10 minutes of not understanding why it wouldn’t solder on. The other one is one end of a really small resistor in a tight corner. I think it’s the toughest point on the board and I messed it all up. I got frustrated and decided to use some extra solder to “encourage” it on. I got sloppy and joind 4 resistors together on accident. I don’t have any desoldering wick, so it’s going to have to wait until tommorow. You can’t tell in the small picture, but the large version is better.

My Mistaek All But 6 Done

The upside to all this is that I’ve become a much more confident solderer. I think I just made that word up.

As a side note Final Fantasy XII was leaked on Sunday. That’s a whole month before retail, ouch. Pretty impressive for such a high profile game. I happened to be up when it was released and hopped onto a torrent with about 300 of my closest friends. It’s not credited to any group in the NFO or release title, just an independent (I swear I just downloaded the NFO, this kinda release is a little hot for my taste.) I checked Console News today and it doesn’t credit it to any group, so the iND must be for real. Anyway, here’s the NFO for anyone interested who doesn’t want a cease and desist from Square Enix.

65 X 50MB
RELEASE: 10/01/2006
RETAIL: 10/31/2006





Chu Moy Amplifier

September 24, 2006 » Geek

Today I started working on my Chu Moy pocket amplifier, named after the creator. I’m working from a set of plans I found at tangentsoft.net which are very good and very detailed. A few days ago I bought almost all the parts from Digi-Key for under $20, and I bought the remaining little bits from Radio Shack this afternoon. An important note for anyone who attempts to make one of these, is that some of the parts listed on the tangentsoft pages are obsolete, and you have to do a little searching through Digi-Key for an equivalent piece.

I’ve never done any serious electronics work. In fact, the only thing I have done is put an EL panel in my Linux Zip-It, which I had a marginally tough time with. I was going to do the 5-Wire hack on it, but the points looked just a tiny bit too small, thus I have a serial d-bus and an RS232 IC lying in a box somewhere. Anyway, I’m off topic. I’ve almost no experience with electronics, thats what this paragraph is trying to get at.

My Power Section
The Power Section

Let me be the first to say, this was a mistake. I don’t know what I’m doing here. This picture is the result of about an hour of work. That’s 6 components and 4 jumpers in an hour. Plus, if I had a picture of the underside, it would be even less of an accomplishment. The camera batteries died, so I do not, PTL.

I am decent with a soldering iron, and I can make nice, smooth joints on the board. The problem is, I bought a generic PC board that doesn’t have any traces, so I need a bunch of jumpers. Getting the jumpers in the right place along with the component and soldered all nice just wasn’t happening. I’m still confident it will work, but it sure ain’t pretty.

I’ve finished the power section, got the op-amp on the board, and most of the other components. I still have to put on another 4 resistors and then wire up the potentiometer (thats a fancy word for volume knob) and the input/output jacks. Once I’ve done that and the batteries have recharged I’ll get some more pics up here and we’ll find out if my skillz were sufficient to result in a working amp.

9/24/06 – As promised, here are some more photos. They’re blurry because it’s dark in here and my camera doesn’t focus well. I apologize for all the white space, something’s weird in my layout. Thanks ray326 :)

Part Deux