1929 Majestic 91

Everything I've done so far has been "headless", which means no monitor. I don't even have a keyboard or mouse that'll work with a Pi. I did plug the Zero into my TV to see if it was booting up (had a bad MicroSD card so I couldn't talk to it) and it was pretty funny seeing something the size of a Hot Wheels putting a command line interface on a 55" screen.

I haven't played with a CD yet. I think Kodi can take a CD input, but you probably wouldn't have any ability to modify the onscreen display. I think that if you plug in a CD player and stick in a disc, it'll be accessible as a drive. Playing it from there should be relatively easy, and the HiFiBerry amp is just a replacement for the onboard sound that would otherwise go out via HDMI. The simplified onscreen display of the track number might be the challenging part, I'm not there myself :)

Love it. Somebody mentioned leaving the patina, 'caused it be worth more. That be right at high values. But whats the difference at under $200? As long as you've looked into it and its worth more as family memories, I like this plan better. Ain't this a site 'bout modding stuff?

I learned a bit about tubes in the 70's and  tube amps for guitars sound GREAT, but a am radio? Nah, make it modern!

My Folks always had their old 'Fridge in the garage... a 1942 'Fridge made by International Harvester!!! Only one I ever saw. They got it used from a cousin that bought it new, when they got married. Other than replacing a starting capacitor in the 80's, had been running non stop the whole time. On of the many things my Dad sold or gave away, 'cause he forgot I had said I was interested! (he did still leave me a LOT of old cool junk to move out of his old garage when time)

Keep posting; cool stuff.

My grandfather was a radio ham. He would be disgusted to what I've done to some nice clean audio signals in the name of making guitar noise.

The Majestic didn't have patina, it was trashy from neglect. There is a difference! You get patina from using something and taking care of it. You trash it by neglect and abuse.

Anyhow, on to the F-63. I spent last night doing some...alternative things. Pics of that later if it works out. Here's a look at the state of the radio, which really doesn't matter to this project but is interesting. To me :)

The whole unit. That five wire plug goes to the speaker. The green wire is the newer repair to the lights. To remove this, you pull off the four knobs on the front of the case and undo three big bolts on the bottom. Unplug the speaker and the whole unit slides out.

Underneath. The snipped modern power wire is clear. The thin green wire is the add-on to power the display lights. The faded red wire just below it has damaged insulation. I suspect the power transformer was replaced at one point - it's apparently marginal in the F-63. You can see how much more work this would be to build than something with a circuit board. Not the neatest point-to-point build I've seen. There's a big floating spiderweb of resistors in one location.

This does not look right. Just out of frame is another solder joint that's come loose. I'll trace it out later, but that might have been what failed on the lights.

The data sheet inside the unit. A 90 day warranty!

These decorative screws attach the speaker to the case. I love the brass insert, this thing was made to be disassembled and serviced.

This is the "window" for the display. It's a plastic sheet (or something similar) and has warped especially along the bottom. In another restoration of a F-63 I've found, they mention polishing this with Novus plastic polish. Not sure how to flatten in out, though. I may err on the side of caution and just clean it up a bit. I don't really want to recreate it.

What's the best tool for working on a 1938 radio? A latest generation 3D printer, of course. We got this reeeeeally nice Markforged unit at work and I decided to put it to the test.

The problem is those little relays you've seen in a few pictures. I'm using them to hook up to vintage switches and to trigger things like the lights. They're actually ridiculously overspecified for what I'm asking them to do, they can handle 10A at 250V. But they're convenient and easy to use. Annoyingly,  they sit on little through hole circuit boards so you can't mount them directly to something.

I don't know if I've done any 3D modeling since 1994. Seriously. But we had that new toy, and the purpose is to learn new things, so I fired up a shiny new copy of Fusion360 (free for personal use for a year!) and started poking around. I made the measurements with an old set of calipers I inherited from my grandfather. Took the file in to work and told the printer to poop one out.

Voila, a custom relay mount. 

The holes in the bottom let me mount it to a solid surface with a screw, and the relays just snap in like Lego bricks. They've got about the same tension on them, which is perfect. Nailed it on the first try. I am really happy about this. I mean, it's not a complex model but I had to get the dimensions just right. I could have made something out of wood or with a bunch of spacers, but this was actually easier start to finish and I learned something. And now, if I need to mount another relay (which I do in the Majestic), I just print up another bracket.

I'll have all the parts I need to finish this thing up tonight.

Something as simple as that to a 3D printer, looks so much better than cobbling something together. Great work. And not so simple to some us Luddite types!

If anyone reading (ie, someone who clicked on a thread about an antique radio and found discussion of tiny embedded Linux computers and 3D printing) wants a copy of the file or even an actual relay mount, just let me know.

Here are the relays - I've become quite fond of these. I'm tempted to use them to make actual logic circuits.

https://www.amazon.com/gp/product/B00LW15A4W/

Today I built the F-63 

Here are all the electronics - the Pi Zero, the HiFiBerry miniamp and the two relays almost all wired up. One relay (the left one here) is connected to the power switch on the radio. Turn it on, and the relay connects a certain pin to ground. This wakes up the Pi. Turn it off, and another pin gets switched. I've got a script running that watches for that pin and initiates a shutdown.

The other relay is connected to another pin on the Pi. When it boots up, that pin goes hot and that trips the relay. This turns on the dial lights. 

Here's the connection to the power switch on the radio. This is actually a switched ground to trigger the relay. The two white wires are the new ones. This is obviously easily reversible in the future, as I just soldered on top of existing connections and didn't have to mess with the wiring any further. The dial lights were already screwed with so my wiring changes - running the power wire to my relay instead of a tube heater - don't move it any further from stock.

I found out when looking for replacement light bulbs that these are 6.2V lights. So I decided to run them at 5V, because I have access to the universal 5V power supply: a USB socket on the little power bar that will run this thing. I used a new USB connector because that is 1000x easier than chopping up an existing cable.

The crazy and interesting field coil speaker has been removed and stored. I replaced it with a $15 full range car audio speaker. No mods to the case, I was able to use the existing fasteners. Ever notice how, the cheaper the speaker, the more obnoxious the claims on the box?

The grille cloth isn't perfect, but it's serviceable. I straightened out the top section and stapled it down.

Installed. The Pi, the relay bank and the power bar are all glued down with 3M Command Strips so I can easily remove them if needed. I also added some strain relief on that power bar. The bar has the aforementioned USB output so it can power the dial lights, and the cloth wapped cord seemed a little more suitable than a plastic one. The wiring looks a little untidy but if that bothers you, scroll back up to the picture of the guts of this thing from the factory :)

And it's done! I still might have to do a little fine-tuning to the Pi, it's cutting out occasionally. I'm thinking I might need an extra amp in the power supply as the miniamp is pulling 600 mA - the CPU may be throttling back due to brownouts. It may also be a matter of increasing the buffer for the audio.

It's fun to use. You turn it on with the power switch and there's a solid double CLICK as the relays flip over. The lights come on almost immediately but the Pi has to fully boot before it can play music - almost like warming the tubes. When you're done, there's a single CLICK when you turn off the power button. The lights stay on for another 5 seconds or so and then CLICK they turn off as well. I wired it that way so I could know when the Pi was fully shut down and safe to unplug. The delays are just enough to give it some character, to make it more interesting. Not that it needed much help there.

So here you go. Imagine Glenn Miller or Dave Brubeck or Count Basie when you look at this picture. It's a great addition to the house.

Next, more work on the Majestic!

Next step on the Majestic...

I wanted that light to come on the front when the speaker was playing. I mean, I had it attached to a switch. But that's not right. What I really wanted was for the dial light to basically act like a status light. So I started poking around with scripts and wiring on the Pi. I was making progress - I could turn a light on and off with a script, and I'd found a way to determine if the audio system was playing audio, which means it was just a matter of duct tape and spit to make it work - when I found something in the "Shairport" (Airplay target) configuration file:

run_this_before_entering_active_state
run_this_after_exiting_active_state
 active_state_timeout

Yes, the service would call a user-defined script when it started working and again when it stopped, with a delay if desired. I figured I'd learned 90% of what I wanted to learn already, and this was a lot slicker than having a script running in the background. I implemented it on my development Pi, hit some roadblocks, figured them out (repeat as necessary) and got it working.

Because pictures are more fun than words, here's the development Pi. I'm working on a couple of things here - testing a new relay type, doing the initial wiring for the analog-digital converter. That white plate, for those who don't play with this stuff, is called a breadboard. It's plugged into the input/output pins of the Pi, and it allows me to make quick and easy connections by simply sticking wires into it.

Here's the Majestic Pi getting assembled. I added a shutdown button so I could gracefully shut down the Pi if necessary, and the relay will switch the light on and off. This is only part of the wiring that will be added, but it's enough to prove the concept and test it all for real.

And we have success! When I start to play music on the Majestic, it turns on the light for the tuning dial. When I turn it off, the light shuts down about 15 seconds later.

It makes the big inert radio seem alive - somehow the light coming on (after more than 50 years) is more obvious than the sound coming out of the speaker. I'm currently playing music just for the simple joy of seeing it lit up :)

Here's another fun job for one of the Pis to do: Pi-hole. It's basically a private DNS server with a blacklist. Or, if that went whooshing over your head, it's ad blocking at the network level. It really speeds up your internet connection, because instead of your computer/phone/tablet having to download ads before an adblocker decides not to show them to you, they never get downloaded. They simply don't exist.

I've got it up and running on the development Pi and it's so cool. It makes Jalopnik actually function and speeds it up quite a bit. Doesn't fix the clickbait content, but hey it's a start :) Either of the two radios has enough horsepower on hand to run this, but the always-on Majestic is the obvious choice.

The Pi-hole is now installed permanently on the network. I've configured the router to use it so that anything on the in-house network benefits. 

And it's a little bit shocking: currently, 27% of the queries going to the DNS server are getting blocked. Some of this is because I was testing on sites that are known problems such as Wired.com and the Gizmodo/Jalopnik family of sites. But good lord. The increase in response is ridiculous. Not bad for something that can be made out of a $10 computer.

I have a new Pi plan as well. My shop is a metal building with an infrared natural gas heater. When it gets down near freezing, the humidity in the shop goes up because, well, water is a byproduct of combustion. But the walls of the shop are cold. This means condensation, and that makes it rain. But not in the cool rapper way. The shop has an exhaust fan, so I run that the problem is solved. Which means it's been running constantly for the last 2.5 months.

The plan is to hook up a little temp/humidity sensor up to a Pi Zero and have it work as a thermostat and a humidistat. Easy enough (he says confidently). Just for fun, I'm going to incorporate a little display so I can see the current state, and maybe add a couple of buttons that let me adjust the temp. I'll also drop in a simple web interface so I can tell my shop to warm itself up if I'm going to be working there. Should be an interesting project. And we are now even further from antique radios...

More work on the Majestic - I found out what was causing some problems with the radio playback today on the Majestic and fixed it. Now it's smooooooth as golden. The little GE is stuttering a bit, I'm going to have to figure it out.

But in the process of making some network changes, I pulled out my old AirPort Express. It had a USB drive attached to it as a Time Machine backup drive for the laptops. A bit of code later and now the Majestic is a Time Machine server, so it's backing up data to a separate drive from the 2TB RAID used by the media server. And the media server has been just about flawless, it's a nice addition to the family. 

Whew.

The last parts for the fancy shop climate monitoring system showed up today. I'll maybe play with them over the weekend...

In reply to Keith Tanner :

I have no idea what you just said, but I like music and I like the looks of old radios.

Since this thread has veered dramatically and comprehensively off the rails, I think I'll start a new one for Adventures in Embedded Computing so we don't shock any more vintage radio buffs and the code pushers can find this conversation.