Hi @ll,
I am curious if someone has done that already.
Í saw that beautiful Music Assistant plugin for home assistant and wish I could connect that to my large vintage radio. But to achieve that, I need a radio signal sender that integrates in home assistant and is selectable in music assiistant as target device.
U guys have experience with that?
I currently run HASS on a pi 4.
FM Radio modulator? 12volt vehicle ones could be pressed into use with a switched 12v DC power aupply controlled by HomeAssistant through a relay board, one switching your modulator, and the other your vintage radio, or you could just embed the modulator inside your vintage radio and just switch the radio through the relay board and the modulator could come on from the same mains power.
The only devices I know of something capable are the bluetooth to FM transcievers. Used to be of value in 'older ’ cars.
Pair your modulator to a HomeAssistant audio to BlueTooth device first.
Alternatively, just connect the headphone output from your HomeAssistant music player to the input of the vintage radio amplifier section via a suitable resistor, just before the volume control, say 10K ohms. Some may have an audio in or microphone connector already in place on the front or rear.
Cheap Chinese USB to audio headphone socket, or USB to FM adapters are still commonly available. The ones for cars will run off 12volts, and some to to 24volts power supply which you may be able to find inside your vintage radio.
You might even be able to integrate a Bluetooth receiver inside the old radio.
It’s not uncommon there is loads of empty space in them.
Yes, i’ve done that. I connected a esp32-s3 as a mediaplayer/speaker via esphome to HA. Music assistant also see those media players. I connected the output of this speaker to the radio module of one off these.
Alecto garden speaker. It’s a very old one
found one that is actually a USB not just a ligher jack form factor: USB Wireless Bluetooth 5.3 FM Transmitter Receiver Car Audio Adapter 3.5mm AUX | eBay Australia
USB side would just be for power so yes they would need to just use the BT connection or 3.5mm connection from the source to connect to it and use it as a relay for the devices they want to broadcast to.
What make and model is your vintage radio?
Might be able to find a circuit diagram and tell you where to connect the wires and bits to make it all work.
In the United States, both (Howard W.) Sams and (John F.) Rider’s Perpetual Troubleshooter published schematics of many radios sold here, so you may be able to find a schematic (assuming you’re in the states, of course.) These are sometimes available online, and usually available on eBay for a small amount if you’re just looking for one unit. SAMS does still maintain copyright on items published after a certain date, so certain ones may not be online. Rider’s is long out of copyright and people freely share these. These have been indexed many times, you should be able to find anything you need with a bit of searching.
Caveat: Old radios can have very high voltages inside, higher than line. They can also have a lot of age-related issues that will slowly destroy the tubes inside. They can have unseen issues that can cause fire. They generate a lot of heat which can burn wiring and other electronics placed inside. Assume anything you touch in an old radio is either hot (heat) or hot (voltage.) Never leave one plugged in when not in use.
Here’s one I worked with recently to make it not do some of those things I just mentioned: Another S-38C on my bench, part 1: Examination and Diagnosis. » Projects from the bottom drawer
Agreed. A bluetooth air gap may be a life saving exercise, especially for valve radios. Most Bluetooth devices have a far higher bit rate than your ears are going to detect with the comforting warm mellow sound of a vintage set.
Having said that, most of the valve radios use 6.3volts for their valve filament heater coils, suitably rectified and smoothed would be perfect for a 12volts DC powered device.
If it is transistor based, most use 15volts for the low audio part and higher for the amp. Again, quite suitable to tap into.
The question is how vintage if looking for circuits. Most manufacturers disclosed their design approaches which should be enough to guess the internals. Most five valve sets follow the same principle, same as most transistor sets. Anything with ICs is fair game however, some going all analog and others all digital, and some hybrid.
Photos would help.
Thank you guys for your feedback.
I have this one Sizilia Ch= Concertino 6 Radio Kuba Kuba-Imperial, G. Kubetschek; |Radiomuseum.org
I dont know if I will ever touch that old school eletronics. 
To scary that I might break things and cannot get spareparts for it.
That’s one impressive piece of equipment!
The Telefunken 6 based unit (in a redesigned cabinet) is from the late 50’s and is truly a work of art, not only for the enormous furniture aspect, but for technical prowess and audio clarity.
Somebody has already developed a BlueTooth addon for the Telefunken 6. See Telefunken Concertino 6 – Antica Radio
The three pin audio input (with the tape recorder symbol) on the back could be used. My German is non existant so wasn’t able to read the various texts for the circuit diagrams, even though the circuit layout is familiar.
The stereo FM receiver can be identified by cables marked input and output going to the main chassis. I would connect your BlueTooth receiver stereo output across the FM radio outputs if the 3pin DIN plug did not work. The connection from the record player would probably be too sensitive and need step down resistors and add too much noise threshold to be useful.
Due to its age and risk of failure of elderly valves and capacitors, I would probably retrofit it with a modern amplifier hidden inside the huge chassis, and leave it for visual enjoyment than risk breakdown from constant use. The six speakers may still be up to it, depending on how well it has been preserved over the years, but the sound would probably be a bit too mellow for any vinyl records being played on the phonograph.
Changing any aspect from the original is painful for me to consider. Preservation of history at this level of grandeur is far more important than having it burst forth with music from HomeAssistant music players. I also note from a superficial browse that the current antique value is not much different to the original selling price more than 60 years ago, something I found quite extraordinary!
Wow, nice looking piece of gear!
“Majestic” style radios tended to switch high voltages on those piano-keys on the front. That wore them out much quicker than normal, and you also have plastic parts failing from age… Using a new amplifier instead of the original unit is probably a better choice, both for your electric bill and your safety/sanity.
Here is a similar project for that style of vintage radio if you ever decide to do the same:
Thank you all again. It was love on first sight. Got that from the german craigslist for 100€… and oh boy… this thing has a sound you wouldn’t believe until you hear it with your own ears.
I am scared to touch it as long as it’s working. I have basic knowledge in soldering, but none in electronics. The knowledge needed to modernize these kind of radios is beyond my scope of hobbies. 
I hoped for non-invasive aproaches via fm transmission and a more simple “plug’n’play” solution for HASS.
I think I might try GitHub - Outdatedcandy92/FM-Transmitter: A USB audio to FM transmitter board
That’s something I might be more confident realizing.
Yes if you don’t want to do any modifications then either making your own USB to FM adapter or buying one as linked previous is your best option to let you tune it to the signal you set on them.
OK, leave your unit alone and get the sound to it wirelessly through the FM receiver.
You may be able to buy the equivalent of the GitHub USB to FM Transmitter project as a cheap Chinese gadget already built, or alternatively cobble up the equivalent.
You can do it with three cheap gadgets:
Plug them all in together, tune your FM station to the transmitter, and play your music to the virtual sound card from MusicAssistant and enjoy in stereo.
Distance between each device should only be a metre or two for best sound.
For longer life, needless power on and off can lead to the filaments inside the valves burning out early, and the large capacitors leaking. Valves are still available, surprisingly still manufactured in Russia for their nuclear EMP proof abilities. A common issue is burnt out 6.3volts globes for the dial illumination, which can easily be replaced by modern LED equivalents designed to duplicate the same shape and warm glow of the original bulbs.
Twiddling the knobs can result in scratchy sound. The potentiometers are becoming harder to source for volume and tone controls replacement but be careful if trying WD40 spray as the carbon residue inside can cause faster degradation. A drop of sewing machine oil where the rotating shaft enters the mechanism should be done very sparingly and should last years. Cooked caoacitors should be replaced with modern equivalents in both capacitance and voltage values. Some restorers hide the new, far smaller capacitors under the chassis, leaving the original ones, now disconnected, for display and authenticity purposes. Beware as some of these larger capacitors have horrid corrosive chemicals inside that can leak, so a regular peek inside the cabinet is recommended. The huge resistors can be replaced by modern ones, again the old ones left in place for show, and the new ones tucked in underneath. The IF transformers are usually ok unless the cabinet has been left out in the weather and has rusted, or has mouse urine on it. In this case, clean up as best as possible without removing any labels or printing on the side of the covers. Never fiddle with the screw adjustments unless you have the appropriate tuning oscilloscope. The tuning capacitors have huge vanes and that is the first thing that is touched and bent by ham-fisted scavengers. Carefully straighten so they dont interfere as the two parts mesh for accurate reception and match up with the front dial. Broken dial cord is easily replaced, often by entirely unsuitable fishing line. Be sure to follow the path of the original so the dial pointers line up with station markings
The mains transformers are usually potted in bitumen (tar) which can get a little soft and smelly if left on for extended periods. If they burn out, they can be replaced by two, one for the high voltage and another for the low.
Any rust in the chassis should be neutralised and protected.
Mains cables and plugs can be replaced by modern ones, especially if the old ones are made of plastic/bakelite which can crumble and deteriorate, with corresponding electrical safety issues.
The outside cabinet should be wiped down with a clean cloth occasionally, and furniture polish can be used to restore wooden cabinets. Never use a damp cloth as the water will damage the finish. The dial is usually brittle plastic by now and should not be damaged by any chemicals for cleaning. Leave as is. Knobs and switch covers can be copied by 3D printing, but be sure to make the finish look antique to match existing ones. Loudspeaker paper cones can have water damage, or be eaten by silverfish. Repair kits are available, but modern speaker equivalents, both in size and impedance are commonly available. Use 4ohm ones for your unit.
I hope the above gives you confidence in keeping your unit intact for historical purposes. Just a few hints from my experience with old units.
With careful use, and regular maintenance, there is no reason why you cannot keep your magnificent unit in top condition.
Years ago I used an OG raspberry pi 1. you bit bang the gpio. like this: GitHub - markondej/fm_transmitter: Raspberry Pi as FM transmitter
