Electronics projects anyone?

[RevDisk]

So, what nifty projects have folks been up to? 

I was talking to Nick, and he mentioned a Pi/HVAC project he was working on. I had a couple sensor projects and figured it'd make a good thread.  Part of this is to hawk a Netduino, which is free for anyone that wants it. It's not the easiest (IMHO) platform, but it's a arduino knockoff so it's still relatively easy for folks to use. If anyone gets inspired, lemme know and I'll ship you your very own microcontroller.


Lately I've been spending most of my time with the BeagleBone Black. It is not a microcontroller, but rather a full PC, for $35. You can directly hook up a monitor and keyboard, and use it as a normal if a bit slow desktop. It just happen to have ports on it handy for directly putting in electronics. I snagged a prototyping/perf board and slapped on a couple sensors. Literally just a photovoltiac resistor, a temperature sensor and a normal resistor.

There are python libraries and scripts out there to make it pretty easy to report back info from whatever sensor you want to plug in. The default Linux OS on the device is frankly horrible, but you can easily slap on plenty of other pre-formatted operating systems, with Ubuntu being the most community supported. Folks also sell pre-formatted SD cards with Ubuntu running on it.
 
I do readings every ten minutes and with a 32Gb SD card (which is about $20), that'll hold oh, couple decades worth of entries on the MySQL database I installed in minutes. With compression, it'd be centuries worth of data.

Live feed of the temp data, using pChart: http://climate.fwdportal.com/


BeagleBone (same apply for the Raspberry Pi)
Pros: It can run off the shelf software, easy ethernet/WiFi, can use USB stuff with ease
Cons: Not good for low power (ie powered off batteries), development can be more complex, doesn't like all sensors


On the flip side is the microcontroller, such as the ubiquitious Arduino. Cheaper historically ($25) and easier to use. Not a full PC, so there's less overhead. You also have a lot less space to store programs or data.

Pros: Cheaper, uses less power, easily run off batteries or solar, easy to use just about any sensor
Cons: Harder to do complex tasks, need add-on shields for storage/networking/etc



So, besides reading the current temperature, anyone else have any electronics projects they've been toying with?

[Nick1911]

As noted, I'm mucking about with temperature/humidity sensors on an HVAC system.  While I'm not quite at the point where I want to really lay out the project in public [yall will be the first to know], here's an "in progress" snapshot:



I'll note that any full-fledged computer system with decent electrical I/O support is very handy for prototyping things.  It opens doors that we didn't even have in the past.

[Regolith]

Umm...I soldered a new 3.5mm jack onto one of my good pairs of headphones because the old one had a short. That count? 

[cosine]

I wish I had time for tinkering. 

[birdman]

Does the 16,000+ element active acoustic phased array (individual element phase and intensity control) with precision video object tracking that's in my garage workshop count?
It only has 1024 pic16 and 64 pic32 micro controllers on it :)

[Nick1911]

Does the 16,000+ element active acoustic phased array (individual element phase and intensity control) with precision video object tracking that's in my garage workshop count?
It only has 1024 pic16 and 64 pic32 micro controllers on it :)

Honestly, I'm impressed by anyone who can really write code to make a micro perform.  I can do what I need to, through various layers of obfuscation -- but my bread and butter has always been physical work with metal.  [That said, professionally I write java for health-care IT.    ]

[AmbulanceDriver]

Um.....  I'm gonna go with....  YES.   (but only if you show us pictures)

[birdman]

Honestly, I'm impressed by anyone who can really write code to make a micro perform.  I can do what I need to, through various layers of obfuscation -- but my bread and butter has always been physical work with metal.  [That said, professionally I write java for health-care IT.   ]

When things have to be truly real-time, you need the level of instruction cycle control only a MCU can provide.

Well, that and I have one of the best (in my opinion) combo hardware/software (especially microcontroller) guys I know doing the details (our very own mangle).

Um.....  I'm gonna go with....  YES.   (but only if you show us pictures)

Pictures are proprietary for now, unfortunately.  But soon...very soon.

The stack of test equipment in the garage lab is growing at an insane rate.
Impedance analyzer, 4 programmable multi-channel power supplies, agilent waveform generators, couple of 4-channel scopes, two high speed 8/16 channel DAQs, and a few weeks ago, we added a laser vibrometer (measures nm level displacements of a spot less than 3-5 microns across.

[AJ Dual]

Assembled/soldered a kit from Make magazine/website that's an infra-red LED jammer.
So when all my office-mates are flying their Syma x107 toy helicopters, they just fall from the sky in unison.

Meanwhile, my Hubsan quadcopter flies merrily on, as it uses 2.4ghz RF control.  

[RevDisk]

Does the 16,000+ element active acoustic phased array (individual element phase and intensity control) with precision video object tracking that's in my garage workshop count?
It only has 1024 pic16 and 64 pic32 micro controllers on it :)

*gigglesnort*

What's the max effective range? Using piezoelectric transducers?

You're making an acoustic time delay device, yes?

[Gewehr98]

Cool!  The air motion transformer drivers in my ESS/Heil speakers are starting to go.  Sounds like Birdman's system could nail down that problem, and proper staging in my listening room...    

[birdman]

*gigglesnort*

What's the max effective range? Using piezoelectric transducers?

You're making an acoustic time delay device, yes?

Not what you think.
Transducers aren't what you think (I actually invented them)
And not what you think
:)

Cool!  The air motion transformer drivers in my ESS/Heil speakers are starting to go.  Sounds like Birdman's system could nail down that problem, and proper staging in my listening room...    

Nope, not what you think :)

[RevDisk]

*perk* Really? So, it's not just an ultra precision compacted radar. Interesting, that. My only other off the shelf guess would be,,,  vortices, perhaps? That'd be interesting in and out of itself, but merely ueber state of the art. Otherwise, I'm deeply curious.

[birdman]

*perk* Really? So, it's not just an ultra precision compacted radar. Interesting, that. My only other off the shelf guess would be,,,  vortices, perhaps? That'd be interesting in and out of itself, but merely ueber state of the art. Otherwise, I'm deeply curious.

Don't bother guessing, I'll go public with what it is in a bit.

[AmbulanceDriver]

When I first read the description, the only thing that popped to mind is some kind of automated accoustic area denial device.

Then I read the level of accuracy you're measuring things to and now I'm not so sure....

[RevDisk]

Ooo, very nifty. And more practical than I expected.

Yea, my projects tend to be more mundane. 

[Azrael256]

Built a headphone amp, and a fuzz pedal.  Repaired a ping-pong/reverb pedal and a digital effects pedal.  Next is a proper bypass modification for something called a "boss chorus." It uses some kind of JK latch thing and the owner wants a clicky switch thingy bypass instead of the soft on/off.

Oddly, I don't have an electric guitar.  I also have very little interest in analog stuff.

Guys at work figured out I can build things and started piling broken gear and components on my desk.  I'm waiting for something ridiculous like a tube amp to show up.

Fitz, don't get any ideas.

[Jamisjockey]

I rubbed a balloon on my head and stuck it on the wall. Then I laughed.

[RoadKingLarry]

I spliced in a repair on my boat trailer lights. I even broke out my big Weller gun. Solder and heat shrink.  Nice looking repair.

Apparently though there is another break in the wiring that I didn't take the time to trace out yet.

After more than 33 years working with electronical doodads and for many years slinging a soldering iron 8 hours a day 5. Days a week, come my time I generally find something else to do for play.

I am however, starting to spec out a solar charging system for my boat. Probably keep it kind of smallish in the 85-100 watt range.

[bedlamite]

Currently building a low budget CNC mill similar to this. Planned use is cutting parts for R/C aircraft, and there may be a walnut AR-15 lower in my future too.

[roo_ster]

Currently building a low budget CNC mill similar to this. Planned use is cutting parts for R/C aircraft, and there may be a walnut AR-15 lower in my future too.

What sort of RC aircraft parts?

[41magsnub]

I spliced in a repair on my boat trailer lights. I even broke out my big Weller gun. Solder and heat shrink.  Nice looking repair.

Same thing here.  Last year I put a new bumper on the land cruiser.  Whatever mental giant installed the after market trailer wiring harness routed the cable through at least 2 different holes on the OEM bumper so I had to chop the plug off.  I forgot about it since I very rarely tow anything.  I needed to tow a trailer Sunday so I wired in a new plug on Saturday.

[RocketMan]

Nothing going on right now.  Just focused on getting my 1900 sq. ft. shop/ham shack/computer room/rocket lab set up in our new house.  Lots of shelves to build, floors to epoxy, walls to paint, electric wiring to put in, network cable to punch down, etc.

[RevDisk]

Nothing going on right now.  Just focused on getting my 1900 sq. ft. shop/ham shack/computer room/rocket lab set up in our new house.  Lots of shelves to build, floors to epoxy, walls to paint, electric wiring to put in, network cable to punch down, etc.

Pics!

[JonnyB]

Currently building a low budget CNC mill similar to this. Planned use is cutting parts for R/C aircraft, and there may be a walnut AR-15 lower in my future too.

Hey, bedlamite! My son writes for a few RC magazines - print and emag both. Perhaps, when t=you're finished, you and he can get together for a product review/intro.

jb