July 24, 2022

Alex designed a printed circuit board for an audio amplifier by himself. On July 24, he put the components onto the printed circuit board he designed for the audio amplifier -- after spreading the paste over the solder stencil. Some of the components are much smaller than a grain of rice. He then put the PCB with the components into his toaster over from Goodwill and got the components to reflow solder. Alex then had to take care of a few solder bridges on the audio IC. Lots of flux helped from a flux pen. Then some normal soldering of components and then the moment of truth. Amazingly, it worked, given the sheer number of things that could have gone wrong! Good sound too! There is a video of the moment of truth at the end of the photos.

Video of Alex getting the audio amplifier working.

November 24, 2019

November 23, 2019

November 22, 2019

November 20, 2019

November 19, 2019

November 12, 2019

February 16, 2019

Alex made a robot at HCC Robotics club over the past several weeks. The robot runs a simple Python program on top of Raspberry Pi, controlled remotely using VNC with a simple python program using a $5 toy car, a L298N motor controller board, a USB power bank, and some miscellaneous bits.

Alex showing his robot to fellow HCC Robotics members.

February 3, 2019

Experiments with a green laser.

December 1, 2018

Alex placed 4th out of 29 teams at the Texas CoderZ CRCC competition in Rockwall, Texas.

October 21, 2018

Alex decided he didn't like that his hobbyist power supply fan only came on when the power supply was driven really hard. So, he took the case off, snipped the fan wires and put in a side channel, low-speed circuit with a couple of resistors in parallel with the bi-metal temperature-switched path. The fan will still go to full speed when the power supply driver gets too hot.

April 7, 2018

Texas A&M Physics Festival

April 6, 2018

March 25, 2018

March 20, 2018

March 19, 2018

March 17, 2018

March 9, 2018

March 3, 2018

March 2, 2018

February 24, 2018

February 9, 2018

February 6, 2018

February 4, 2018

February 3, 2018

February 2, 2018

January 25, 2018

January 18, 2018

January 13, 2018

January 7, 2018

January 2, 2018

December 28, 2017

December 24, 2017

December 23, 2017

December 21, 2017

December 12, 2017

December 9, 2017

August 6, 2017

August 4, 2017

Alex and I brought six electronic demos for Take Our Sons and Daugters to Work Day.

July 29, 2017

Alex received an early present for his birthday: a Tesla coil! It can make music.

July 4, 2017

Alex demonstrates that you can transmit sound with light.

July 1, 2017

Alex's entry to the Flashing Light Prize 2017

March 25 16, 2017

Alex used a class-D amplifier, an old iPod box, and some parts from Radio Shack to create his own amplifier. He then hooked it up to some salvaged speakers he put in some cardboard boxes. It worked the first time.

March 16, 2017

March 13, 2017

March 12, 2017

Alex wanted to know what salt and salt water did to an electric motor.

February 26, 2017

December 30, 2016

December 25, 2016

December 24, 2016

December 19, 2016

December 15, 2016

December 10, 2016

December 8, 2016

December 7, 2016

November 15, 2016

Simple calculator in the Scratch programming language

October 16, 2016

Alex and I built this soldering fume extractor. A 20 foot dryer duct vents to a panel that fits in a window.

September 9, 2016

Lego Differential Gear with Motor

August 27, 2016

Alex built a Lego rope crawler with a little help from dad.

July 31, 2016

Alex received a 50 watt and a 100 watt LED array. Here he is testing one of them at 25.8 volts driven by an adjustable boost converter.

June 9, 2016

I have no idea what was going on here. Alex with some... friends.

June 3, 2016

Alex won a Parrot Jumping Race drone.

More photos:

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