Water Tower Electronics Installed

With the last gremlin exorcised from the electronics project board, I’ve turned the workbench back to physical mode. During testing, I found that the limit switch was not in fact making contact with the linear actuator. I considered hacking it, but it was easier to tweak the design of the bracket and print a fresh […]

Back to the Breadboard

So, it turns out there’s such a thing as a pull-up resistor that pulls a pin away from ground so that when the pin is shorted to ground using, say a micro-switch connected to a valve rope on a water tower, the microcontroller can detect the change. Without the pull-up resistor, the input is said […]

Water Tower Circuit

The breadboard for the water tower has sat on my desk long enough that it finally transcribed itself into a diagram to start making the circuit permanent. Despite the apparent complexity, it is in fact just four simple circuits mediated by software in the microcontroller: I’m certain this could all be achieved with hardware, but […]

Retreat to known ground

I’ve put the debacle of the micro connectors and missed resistor behind me, and as I said, I’ve decided to revert to connectors I know and trust. These are harvested from an IC socket, and are quite robust, but also big. Okay, big is relative in our world: I often tell people that a lot […]

A bad week for electronics

You’d think that if your father had a doctorate in electrical engineering, at least a little wizardry might have rubbed off! Nope, he kept it all to himself, apparently. The story starts with the Hall effect sensor, which the ESU decoder wants to synchronize the exhaust sound. Countless YouTube videos make this gizmo look trivial, […]

622’s tender cable

I struggled a little bit with whether to simply extend the leads from the tender-mounted decoder so that they could connect with the locomotive, or whether to create a cable with connectors on both ends. In the end, I decided on a cable, rather than having to deal with an obscene length of wires hanging […]

Motor and light connections

One thing I’ve learned in my short career as a locomotive builder is that I take my engines apart a lot. It won’t do to have soldered connections holding the boiler where the lights are to the chassis where the wheel rotation sensor is and to the motor. Fortunately, it seems like the 1mm headers […]

Learning about really tiny connectors

The 1mm connectors arrived from Digikey this week, and rather than leap straight in and wire up a decoder, I took the unusual step and practiced first. I’m glad I did! The connectors are delicate. Indeed, they barely hold together. I found that without a bead of CA to keep the pins in the plastic […]

Really tiny LED

Somewhere between here and the other Vancouver, a package of gubbins from NGineering has been waiting for almost a month. The package contains some solder strippable magnet wire, the recommended flux and a handy-looking tool for holding the wire together with the tiny surface-mount LEDs that are available today. Tim Anderson of NGineering sent the […]

Really tiny connectors!

I was feeling pretty smug about having thought to include a wiring channel along the top of the boiler to make room for marker and headlight wires. Then I started to think about how to get the electricity from the decoder to those wires, and how to make it so that everything can come apart, […]