Diagnosing Watches With Electronics

I've been fascinated by mechanical watches since I was a kid. Little machines on the wrist, marking out the passage of time with an unexpected level of accuracy, at least if the watch is in good shape.

To measure accuracy and diagnose issues, watchmakers use a watch timer which listens for and measures intervals between ticks. However, the tools are rather expensive for hobbyists, such as yours truly.

Fortunately, free or low-cost options like Watch-o-Scope ease the burden, but require a sensor and preamplifier. Here's my take on this fun little preamp project.

Soothe and Glow doesn't light up

Our little girl goes to sleep easier when we have a Fisher Price Soothe and Glow running. One of them didn't light up, and I fixed it. But not before my wife bought another one. Here's what was wrong.

Pi Touchscreen and Lightning Bolt

I've been working on some neat-o projects with a Raspberry Pi 7" Touchscreen on a Raspberry Pi 2 for a few weeks.

But, the Pi has been plagued by the yellow lightning bolt icon, which means "your power supply sucks".

Nothing I've tried, until now, has fixed it. I've been through several phone chargers in 1A, 2.1A, and 2.4A varieties, several USB cables, and I've tried a Pololu 3.5A step-down switching regulator, and my own prototype 3A step-down regulator (I think I broke it?!)

My solution: power the touchscreen and Pi from independent phone chargers, after disconnecting the 5V jumper between them. Hope this helps someone else.

Subscribe and stay tuned for a future article on my Jeep-mounted Overland Expedition Pi with offline Mapping, Satellite Telemetry and Messaging to HQ, and APRS.

My Western Electric 302

I've finally fixed my only vintage phone, an old Western Electric 302, and thought I'd share the old telephones' electro-mechanical guts.

Pulses

These old phones are how dialing a number became a thing. Instead of push buttons and DTMF, rotary telephones send pulses. And not with a 555 timer, either...