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Bad Desk Lamp + 3D Printing = Cool Camera Mount + Useful hand Magnifier

Useful 3D Prints

Useful 3D Prints

I recently purchased a hot-air gun + soldering iron station from X-Tronic which came with a desk lamp magnifier.  The desk lamp was not functional so I took it apart to fix.  It was made so poorly, I considered it too dangerous to use.  It went on the scrap pile.

Today, I decided to make use of it.  The base with its flexible stalk became a nice mount for my new webcam. The desktop magnifier part became a nice large handheld magnifier.

I designed the parts using Fusion 360 and a digital caliper.  Printed on my Creality CR10 using Maker Geeks Raptor Steal Blue Filament.  Note the blue magnifier handle and the blue bit on the lampstand where the camera is attached.

This will be my latest answer to the common question…  “What USEFUL things can you do with a 3D printer?”

Continued…

Posted in Uncategorized.


AA Battery Pack to 3.3V for IoT Projects

AASwitcherTest1I tweeted about my experiments with the AAT1217 switching supply controller a few days ago.  I found the chip in a product design I was evaluating. It looked like a great answer to the power problem in an IoT project I’m working on. 

I ordered a few from Mouser and some breakout boards to try.  My first experiment was to fire it up on a breadboard with a load and a AA battery pack.

I recorded the performance while the batteries drained into a constant load.


 

Result Summary

  • Rock Solid 3.3VDC at 75mA continuous 
  • More than 15 hours. I missed the very end, it went longer.
  • From a pair of AA Duracell Alkaline batteries.
  • Simple to use, 1 inductor, 2 caps and a resistor

Results

Time hr:min Input Watts In Output Watts Out Efficiency
0 ? Fresh ? 3.3V@75mA 0.258 ?
1:00 2.93V@105mA 0.308 3.3V@75mA 0.258 84%
1:15 107mA   3.3V@75mA 0.258  
3:25 2.65V@118mA 0.313 3.3V@75mA 0.258 82%
12:00 2.30V@140.5mA 0.323 3.3V@75mA 0.258 80%
14:15 2.10V@149.5mA 0.314 3.3V@75mA 0.258 82%

 

Some data is missing above. I was doing this all by hand and just stopping by now and then. The test ran much longer than I expected it would.  I had to sleep.  The 12:00 reading was an unexpected wake up with the 14:15 being a return to bed mark.  The pack was all but dead at this point, but I don’t know how much longer it took to die completely.

Test Circuit

I used the example circuit from Skyworks for the AAT1217 breadboard. The part was a pain to solder to the adapter I had. The adaptor was for a SOT type package with different spacing, but I made it work. 

SchTestThe AAT1217 only needs an inductor and two caps.  A resistor is used to hold the enable high. The output was 3.3V with about 100mV of high-frequency noise/ripple.  I added a 0.15uF ceramic cap to clean that up a bit.

 

 

Parts Used

Part Qty Source
AAT1217ICA-3.3-T1 1 Mouser
4.7uH Inductor 1 Mouser
4.7uF Al Elec Caps 2 bench stock
0.15 Ceramic Cap 1 bench stock
1MOhm Resistor 1 bench stock
22Ohm Resistor 2 bench stock

 

The 22Ohm resistors were used to make a 44 ohm load. At 3.3V this would be a continuous 75mA load.

Observations

The AAT1217 works great.  I will do some more test, but I plan to use it in future projects as the battery power solution with 2 AA battery packs. 

Battery lifetime was considerably longer than expected. I probably have a flaw in my test somewhere.

Based on discharge curves an Alkaline AA would give about 2.4A/hr @100mA and discharge to about 1V. The charge after about 1V is not significant. I estimate that the batteries should have drained in less than 8 hours.

The AAT1217 is specified to run down to 0.8V which would pull the pair of series AA batteries down to 0.4V each.  That might yield some more time but not double the estimate.

My assumptions are that a AA battery is all but dead when it’s at 1V. But that might be wrong while under load. The load was close to the 100mA load a AA is designed for.

Efficiency was much less than expected. I was hoping to see closer to 90% which would make a significant difference in battery life.  I’m thinking the inductor used is not the best for this application. I chose it to be easy to use in a solderless breadboard.  I plan to get a few better parts when I do a more controlled test.

I used a new Rigol DM3058E and a Fluke 175 for measurements.  I hoped to use just the Rigol as it should be able to display two measurements, voltage, and current, at the same time but I did not figure that out.

The Rigol DMM also has an easy to use serial output so I could record one of the data values simply by logging it. I might create a QT app to do a DMM logger, especially if I can get the meter to do both measurements.

When I repeat this test, I’ll pull out a device  I designed and built if for some consulting work recently. It could be adjusted to be an ideal tool for this kind of testing.

Posted in Uncategorized.


$14 GM328A Component Tester + 3D Printed Enclosure

GM328A_2GM328A_2I purchased a “GM328A Transistor Tester Graphic Wave Signal LCRRLCPWMESR Meter Inductance” from Banggood. It came as an assembled unit and tested out very well on my bench. Unfortunately, it did not come with an enclosure.  So, I printed on one my TAZ5 3D Printer.  In this article, I describe the component tester and some experiences with 3D Printing the enclosure.

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Posted in 3D Printing, Development Tools, Discovering, Interesting, Parts, Projects, Review, Scrounging, Scrounging Parts, Tips, Uncategorized, Workshop Tips, Workshop Tools.

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PCB Supplier Review–PCBCart

FirstBuildWe had a PCB made for the ESP01 Neopixel adapter project featured in a prior post. In that project we used an ESP826 to create a web site monitor. In this post we do a review of the board supplier, PCBCart.  The quick summary is that they did a great job for a reasonable price and I had the boards in about 10 days.  Read the full review after the fold…

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Posted in Development Tools, Discovering, Interesting, Projects, Review.

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ESP8266 Web Site Monitor

Breadboard

Using an ESP-01 module with the Arduino IDE to make a website monitor.

Pictured here is the breadboard which runs 24/7 to monitor this web site.

I’ll describe each part as we walk down the image to the left.

Neopixel strip.

6-Pin header I used for an FTDI

Big red button

ESP01 breadboard Adaptor

ESP01 module

BreadboardBuddy Pro , from Tindie. Used for USB to UART serial, reset button, and power supply.

More about each of these below.

 

Continued…

Posted in Ideas, Interesting, IoT, Microcontroller, Projects.

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uCHobby site on new hardware.

Those of you that visit often have probably noticed that my site has been down often. The problem with that server has not been definitively located so we have moved to a new system. We are looking forward to getting back to regular projects using the new Arduino, Raspberry Pi and ESP8266 boards.

We have also gotten into 3D printing, it is an addiction, have been designing and printing a bunch since Christmas when a LulzBot TAZ5 was added to the lab.  If you have been watching the Twitter feed (uCHobby), you have seen some of the recent creations.

For new toys we have an Arduino Zero, Arduino 101, and the OAK boards from their Kickstarter.  Look for or suggest some projects using those.

Posted in Arduino, Kickstarter, uC Hobby Site.

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Lasers from Scrounged Star Shower

Lasers

We bought 3 Star Shower Christmas lights to use around the home. These devices cast a grid of sparkly "stars" and look awesome on trees as the tree moves in the wind.  The "stars" are creating using a red and green lasers passed through a diffraction film.

Only one survived the rain.  The other two found there way to my bench for laser extraction.  I found several items to use in future projects.

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Posted in Discovering, Hacks, Parts, Projects, Scrounging, Scrounging Parts.

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China Goodies – Gearbest.com – Arduino Bits

A review for some Arduino related items we recently received from Gearbest.com. A cheap Arduino Mega compatible board, LCD/Keyboard shied, Acrylic mounting plate for Arduino and a simple cable.  Each one with some details on cost and function. Click on the pictures to visit the product page at Gearbest.

Generally, I’m amazed at the variety and often surprised at the quality of the products from China, considering the price paid.  Yes much of it is lower quality, you are not going to pay $1 for something that would normally cost you $100 and be happy with the result.

One of the major differences you will notice when purchasing from China is the time it takes to receive your items. Typically you will wait 2 or three weeks but it could take longer. You will also notice that most suppliers don’t charge for shipping which surprises me.

The language barrier is evident on the Chinese sales sites. You will notice that everything seems to be Arduino compatible, even things like LEDs… They have picked on the Arduino craze and milk it like crazy.  The descriptions of  the products is often strangely worded and it’s often clear the writer does not understand the product or the market.  But it’s good enough that you can find what you need.

I wonder about starting a consulting gig, where I would go to these sites and get paid to clean up the product descriptions.  They ought to hire some Arduino nerds to clean up things, they would benefit in more sales.

 

LCD1602 Character LCD Keypad Shield: $4.47/each

Pretty much exactly what you see.  A standard 1602 2×16 character display with backlight and 6 buttons.  The LCD is interfaced using 4 DIO signals and the keyboard is done using a resistive ladder trick so that only one A/D input is used.

One of the switches, on the far right, is a reset button. One complaint on this.. it’s easy to hit reset when you mean to tap a regular key.  Also, it can take some tweaking to get the values just right in your code to read the switches.

There are other sources for the same design, I feel that this lower cost version works fine.

Arduino Compatible DIY Mega 2560 R3 Board and Keypad Shield 1602 LCD Board: $22.95

This is a combination of the above LCD Shield and an Arduino Mega 2560.   Read above for more about the shield.

The Arduino Mega works fine and seems to be of high production quality. The quality on this is apparently equal to any board I’ve ordered without regard to the supplier.

My biggest concern here is that it feels wrong to get so much for so little in cost. I personally would order my Arduino boards from a local registered supplier such as Sparkfun for $50/each.   With that said this board works great and is very inexpensive, if you are on a tight  budget and don’t mind waiting…

 

Arduino UNO R3 Compatible Acrylic Platform Plate: $2.08/each

This acrylic plate is convenient to use with your solderless breadboard to keep your wires from pulling out of the Arduino connectors when things move.  Not much else could be said about this product. It works as designed. Simple and inexpensive.

 

 

Extension Cable for Arduino – 8.5 Inch / 21.5cm:  $2.04/Each

Another simple product, just an 8-pin header connector cable. Funny they mention Arduino in the name but no Arduino I know of has an 8-pin header. Some have a 6-pin one…

The quality is good and the price is amazing. These kinds of cables require hand assembly which drives the cost. In China, labor cost are low, obviously.

Comments Please: Let me know in the comments what you think.  Have you found a great deal, bad quality, etc…

Posted in Arduino, Development Tools, Discovering, Electronics Links, Interesting, Review, Tips.

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VoltLog Blog Shout Out…

VoltLogLogoMy old friend Florin has a very neat video blog called VoltLog. Looks like I’m going to be spending a few hours catching up. Maybe he will be as famous as David Jones’s EEVBlog some day. Go Florin, Go!

Posted in Discovering, Interesting, Uncategorized.


ESP8266 IoT Paired LEDs

ESP01breadboard This project/experiment uses two ESP8266-1 modules to make a set of paired LEDs. Each module has a button and an LED. They connect to an MQTT broker to share  the LED status. Press the button on one module and it’s LED comes on, it sends that button to the other module and it’s LED comes on. Press again and both go off.

Think of this like a signal system. You want your wife to call you, instead of interrupting her, you signal. One of these modules would be placed in the kitchen, the other  at the office on your desk, yes, sexist I know. But for this example, assume we are talking about June and Ward Cleaver.

Ward wants June to call but does not want to interrupt her, he presses the button, his light goes on and seconds later the paired module lights up.  June notices her’s go on as she is making cookies for the kids. She presses the button to let Ward know she got the message. Ward’s light goes out seconds later, he knows his good wife will call when she has a moment.

I imagine there are a lot of uses for a signal pair like this…

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Posted in Development Tools, Ideas, Interesting, IoT, Projects.