May 29, 2016

Alex in a box.

May 24, 2016

May 22, 2016

We received a tour of Houston Public Media (Houston PBS and Houston Public Radio) from radio host Eric Landau. Eric answered all of the kids' questions, going into as much detail as they wanted. (And of course Alex wanted lots of detail.)

May 21, 2016

April 09, 2016

Fifth year Alex has been to the Texas A&M Physics Festival

March 27, 2016

January 30, 2016

January 16, 2016

Alex soldering a programmable LED matrix display

December 11, 2015

MSP430 Fader Oscilloscope

November 14, 2015

From my twitter account: "A young engineer telling @yertnamreg & @universiTI what he'd do w/ a @txinstruments Launchpad at @HouMaker #mfh2015"

From my twitter account: "Alex (9yo) successfully picked a one & two-pin lock today @HouMaker thanks to @dc713hou #hmf2015"

Alex practicing his soldering skills at the 2015 Houston Mini Maker Faire at the George R. Brown Convention Center.

Dad helping out Trey German at the TI booth at the 2015 Houston Mini Maker Faire.

The Houston Maker Faire's (@MakerFaireHou) Twitter page on the days up to and including November 14th. Notice someone? I think this was a photo taken at the 2014 Maker Faire Houston at the Stafford Centre.

October 31, 2015

A rotor from a universal motor from a vacuum cleaner. Universal motors can run with AC or DC.

September 8, 2015

Normally on an Arduino Uno, you can't output a voltage except for 0 volts (LOW) and 5 volts (HIGH). You can pulse-width modulate, but that is still alternating (very fast) between 0 and 5 volts. Alex and I figured out how to make a quick-and-dirty digital to analog converter (DAC) out of a resistor and capacitor to get values in between 0 and 5 volts. Technically, this circuit is called a single-pole low-pass filter. Alex made his DAC out of two Snap Circuit parts.

Helpful links:

The output of the DAC.

Code for the pulse-width-modulated output that the DAC will turn into a sine wave.

Alex and I figured out how to spin a motor from a hard-drive. It is not as simple as just applying voltage because the motor is a "three phase" motor. You have to alternate voltage through the three windings with increasing frequency to get the motor to spin. We did this using an Arduino Uno and some simple code.

September 7, 2015

We received a digital oscilloscope from a great gentleman this weekend. Alex and I have been having fun learning about how to use it.

September 2, 2015

August 30, 2015

Alex and I made a musical instrument out of the capacitive sensing Bare Conductive board and a few alligator clips connected to various conductive items.

July 26, 2015

June 7, 2015

Alex finally completed his robot arm. There was a lot of assembly.

You can play and look at the code for Alex's Scratch game shown in this video by clicking here.

May 6, 2015

We programmed an Adafruit NeoPixel Ring (16 elements) today with an Arduino Uno. These individually-addressable RGB LEDs are really bright. The capacitor is to guard against inrush current and the resistor on the data line is to protect the first LED in the chain from voltage spikes.

May 2, 2015

We built an 14 watt op-amp kit from We powered this 8-Ohm speaker and later another larger 8-Ohm taken speaker from a guitar amplifier.

More photos:

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