I picked up a Guohetec PMR-171 portable SDR recently. It’s a compact manpack-style transceiver—roughly double the size of a Yaesu FT-817, or comparable to a typical 100W rig—covering HF through UHF with FM, AM, SSB, and even DMR support. The problem? The manufacturer’s programming software has limited capabilities and is completely undocumented. Coming from other radios with proper CPS (Customer Programming Software), I wanted to understand how this one worked.

A somewhat common issue with these radios is losing all audio. If a unit’s built-in speaker doesn’t make a pop sound or power-on tone when powered on — and the codeplug checks out fine — the audio amplifier has likely failed.

The VXR-1000 is a mobile repeater meant to be used with a mobile radio in a vehicle. Since these 5W output analog radios are designed for interfacing with other equipment via a single dsub connector and are fairly compact, they’re good candidates to use as an embedded radio in various industrial applications. In this post I document what I needed to do to get one up and running.

For Disneyland’s 70th anniversary, they released this giant lightup key which contains a pin which you can unlock by inserting the key into various locks around the park. I decided to retrofit the key with an ESP01 running WLED.

Here’s a quick post documenting the LCARS graphics I made for my Anytone AT-D878UVII handheld.

About a year ago, I began volunteering at the Los Angeles Live Steamers Railroad Museum, and quickly felt the need to build myself a train to zip around the club’s ~1.5 miles of track located in the picturesque northeast corner of Griffith Park. Rather than build a prototypical locomotive, I decided to make what’s commonly referred to as a “pedal car” with some unique features.

A few years ago, I built some hardware to allow an oscilloscope to be used as a VGA display. I often use the photo above as my profile/avatar online and get asked why there are crosshairs on me… here’s how it works!

The basic LEDs that come in the Mickey sorcerer hat that Disney sells are rather pathetic. We can rebuild him. We have the technology.

This summer I started riding a motorcycle, and while stuck at home, I designed and built an auxiliary LED indicator system for added visibility. The system uses addressable LEDs, allowing the compact controller with an integrated power supply to manage potentially hundreds of LEDs.

For my senior project, I’m working on an embeddable lighting controller, with the creative working title of Embedded Lighting Controller, which is being designed to provide flexible lighting control/drive in an extremely compact package.

For a number of projects I’d like to work on in the future, I needed a development board of sorts for testing both hardware and software.

For TwinkleWorks’s new line of RGBW LED strobes, we needed a new testing assembly. This unit automatically tests each of the LEDs’ colors as well as the strobe fixture’s temperature sensing circuitry.

The La Cañada Flintridge Rose Parade float is equipped with a custom-built intercom and radio system to allow the float’s crew to communicate both within the float, and with external crew. Since the intercom box is mounted in the middle of the float where it’s not easily accessible, we needed some way to be able to remotely control the radio.

Following my previous project involving accessing my car’s CAN bus, I wanted to take CAN control further by making a custom controller that can interface with a vehicle to control various accessories.

Have you ever had a piece of equipment that really REALLY doesn’t belong in your car, but you want to install it somehow? Well, I had this problem with my Whelen… electric airhorn….