This project was started as a way to bring new life to an old 1940 radio: the original electric circuit will be kept as is as much as possible, the "retro" look will remain, but modern electronics will be added to implement a networked alarm clock.
But reality caught up with me, in the form of first 1, then 2 little monsters, of the relentless, sleep-depriving, yet addictingly lovable kind... As a result, what was intended as a few months project turned into a multi-year on and off adventure, that isn't even quite finished yet.
The starting point was a tube radio from the late thirties that somehow ended up on my shelf. The Bakelite exterior was (and still is) broken in several places, but if the frequency dial was set properly an actual radio station could be heard behind a loud buzz... At about the same time, my wife and I decided a better, networked alarm clock would be nice, and I figured that with a "bit" of work, the radio could be turned into what we wanted, with vintage looks as a bonus. I settled on the following features:
Keep the radio in a working state, but repair the exterior, and fix the parts of the electronic circuit that needed fixing (at a minimum to remove the annoying buzz).
Use a Raspberry pi as the brains of the alarm clock: playing webradios or MP3s from a network share is easier from a Linux-based host rather than from a microcontroller, a good number of GPIOs would definitely be needed, and the pi broad community support would help with the implementation of some specific features (more on this later).
Try to reuse the old radio speaker for the alarm clock: it is a fairly large one that seemed to provide decent sound even today, and fitting an additional one in the Bakelite chassis would have either altered the looks, or muffled the sound.
Provide a switch on the back to alternate between sound from the tube circuit or the Raspberry pi.
Use Nixie tubes for the alarm clock display: technically, it is a bit of an anachronism in a radio from the thirties, but it blends well with the visual style of the radio.
Use a web interface for most of the alarm clock configuration and keep manual controls for simple stuff such as stopping the alarm or setting the volume.
Add a rotary encoder connected to the pi. The radio already had 3 rotary controls, but controlling them from the pi would have been non-trivial, and there was a natural place for a fourth one.
Add 3 capacitive touch sensors: they're fairly simple to add mechanically, and since they're invisible they don't impact the look of the radio.
That's a long first post. I'll dive into various parts of the project in the following posts, again, reality permitting...