At the height of the Cold War, those of us on the western side of the wall had plenty of choice over our radio listening, even if we stuck with our country’s monolithic broadcaster. On the other side in the Soviet Union, radio for many came without a choice of source, in the form of wired radio systems built into all apartments. [Railways | Retro Tech | DIY] grew up familiar with these wired radios, and treats us to a fascinating examination of their technology, programming, and ultimate decline.
In a Soviet apartment, usually in the kitchen, there would be a “Radio” socket on the wall. Confusingly the same physical dimension as a mains socket, it carried an audio signal. The box which plugged into it was referred to as a radio, but instead contained only a transformer, loudspeaker, and volume control. These carried the centralised radio station, piped from Moscow to the regions by a higher voltage line, then successively stepped down at regional, local, and apartment block level. A later refinement brought a couple more stations on separate sub-carriers, but it was the single channel speakers which provided the soundtrack for daily life.
The decline of the system came over the decades following the end of communism, and he describes its effect on the mostly older listenership. Now the speaker boxes survive as affectionate curios for those like him who grew up with them.
You probably won’t be surprised to find twisted-wire broadcasting in use in the West, too.
Thanks [Stephen Walters] for the tip.
I wish I’d known about this before reading George Orwell’s Nineteen Eighty-Four (1949). This adds a new dimension to the 2-way TV in every home.
This is gonna be juicy.
Reminds me of “Drahtfunk” here in WW2 Germany..
“Draadomroep” in The Netherlands. And they took in a wired signal from Brussels, so maybe Belgium had it as well.
Makes sense, can’t receive foreign broadcasts, goes into any building with electricity (wired at the same time), and puts the party’s voice in every home. Sounds like an ideal technology for a totalitarian regime, and it’s cheap to boot.
It’s replacement is the smart phone where small screen size and decreasing attention spans they help to create hamper actually reading an article below a click-bait headline. It’s a GREAT political propaganda and official narrative distribution device. AI generated answer to my query: “About 59% of smartphone users share links on social media without reading the articles, according to research. This indicates a significant number of people share content based solely on headlines.”
Did your AI provide you a citation for that statistic? It has a “80% of percentages are made up on the spot” feel to it.
83.29% of all statistics are made up. Adding a few decimal places increases the believability.
I have a couple of them, I really want to build something to get them to play audio from any source, but I have never gotten around to it.
The easy solution would of course be to open them and rewire them to be only speakers, but they are sealed (maybe it is the model with microphones in them) and I want to keep them sealed.
PA systems work the same way. You could use a 25 volt PA amplifier to drive a bunch of them or use the transformer for a PA speaker to step up the voltage from a normal amplifier to drive one of them.
I have a couple of them, I really want to build something to get them to play audio from any source, but I have never gotten around to it.
The easy solution would of course be to open them and rewire them to be only speakers, but they are sealed (maybe it is the model with microphones in them) and I want to keep them sealed.
I would be inclined to replace input and speaker with instrument jacks and use it as a preamp device.
More like a one way intercom than a radio …
So if you accidentally plugged it into a regular outlet (awful design btw) would it instantly burn out, or was it robust enough to reproduce an extremely loud 60hz hum? Or whatever frequency commie power mains was
Guessing (because I will not follow video links…)
These are normal 60Hz(or whatever standard) devices, that have an additional circuit that demodulates audio from a higher frequency carrier that is also on the same line.
In a normal socket it should do nothing. It would be powered, but the audio circuit wouldn’t have any high frequency signal to demodulate.
The same should work in reverse.
A standard electrical device should work in the radio socket, since the higher frequency carrier would just be line noise. Though, I’m guessing this socket would be fused to a much lower power rating if it was intended to be used for these radios.
None of that turns out to be how it worked. The “radio” does no demodulation, it’s just a step down transformer, a potentiometer, and a loudspeaker. The socket provides a 30 V baseband audio signal.
Yeah that’s what I was getting from it, no real components besides the speaker and speaker transformer… Kind of like the PA box mounted on the wall in school back in the old days, the one the principal would use to crackle and squawk at the entire student body in a totally illegible voice, something out of a cartoon.. But then later they mention newer models having different tunable stations. That would be more involved
When I was a child I had headphones which were supposed to plug in such radio’s socket. Of course, since the sockets were the same, I tried plugging them in mains outlet.
And yes, I did hear the 50Hz sound (or some harmonic of it). I was afraid that the headphones would burn but they didn’t (I had pluged them just for few seconds).
Ha nice, somehow I suspected it was robust enough to deal with it… I didn’t have such things when I was a kid, but I still plugged an old alnico speaker into a wall outlet once just for the joy of it, and to get yelled at by my dad when it suddenly turned into a bright blue flash that made everyone have to open the windows and go outside for a few hours. I still got a couple moments of extremely loud 60hz hum out of it before it died
Right at the beginning of the video he does exactly that, and there’s a very loud 50Hz hum.
“The radio was not damaged even after I accidentally gave it eight times the voltage it was designed for.” So they knew that people would plug it into mains and the choice of distribution amplifier inside matched.
Ah thank you, I have a policy not to click through on youtube video articles
High voltage utility-scale wired audio distribution. Wild.
Wondering if the audio signal was ever modulated onto a carrier at all, or did they just take a megawatt of baseband audio up to high voltage and distribute it like that. Can’t think of a reason why you couldn’t just transformer it up to 34kV or whatever you like. The old vacuum tube amplifiers typically had a step down transformer to drive common 8 ohm speakers (1940s tec, anyway), so .. why not just run the voltage up instead?
that’s all covered in the video; it started out as just baseband audio distributed as if it were mains current, complete with high voltage long-range transfers transformed down for consumption. but towards the end of these things’ era they apparently started frequency shifting two extra channels onto the same base signal, up in the ultrasonic range. needed more complicated receivers, but stayed backwards compatible.
that was probably inspired by this same system, i suspect. (or the equivalent Dutch and/or German ones other commentators have mentioned.) i guess it must’ve had a cultural impact well beyond the east bloc, it’s not as if it were any secret.
strange for me to think, that is. i was a child in cold war-era Finland, yet somehow i never knew any of this had existed until well after its time was gone. odd to think i was just that oblivious a kid, because logically it must have been a known thing when i was growing up — it would’ve been just across the border, after all, not like my country didn’t have connections eastwards…
The speakers worked like a tannoy (like this https://www.tannoy.com/product.html?modelCode=0302-AAT ) Tube amplifiers have a 100V output transformer, and the single speaker had a transformer inside making the maximum power when a 100V signal was present at terminals, the big advantage is that you can wire any number of speakers provided that the total power used by the speakers is equal or lower to the amplifier.
You need an output transformer on a tube amplifier to match the output power.
Nowadays a better route is to use powered speakers, and have an analog audio signal or better a digital audio signal for audio distribution on PA systems, because a disadvantage of the 100V system is that is difficult to EQ the speakers depending where they are mounted.
In the British TV show The Prisoner (Patrick McGoohan) they had a similar set up with a “radio” in every apartment and loudspeakers outdoors.
that was probably inspired by this same system, i suspect. (or the equivalent Dutch and/or German ones other commentators have mentioned.) i guess it must’ve had a cultural impact well beyond the east bloc, it’s not as if it were any secret.
strange for me to think, that is. i was a child in cold war-era Finland, yet somehow i never knew any of this had existed until well after its time was gone. odd to think i was just that oblivious a kid, because logically it must have been a known thing when i was growing up — it would’ve been just across the border, after all, not like my country didn’t have connections eastwards…
https://www.youtube.com/watch?v=p0SBaAJPXAo
German, Swiss and Italian system were different, they used telephone lines, and the signal was AM modulated in long wave range, and with wider audio bandwidth than regular LW/MW radios. One could used a dedicated receiver, or using an adapter circuit connecting the telephone line to the antenna connector of the radio, a regular radio.
The service was discontinued because was mainly incompatible with ADSL, because it used the same frequencies on the wire.
These things have started turning up on eBay in increasing numbers over the past few years, its only the cost of the postage that’s stopped me buying one to make into a Bluetooth speaker.
We had it in uni dorm (built in 2016), but never really listened to it. I think it was mostly for emergency situations broadcasting. Older people still listen to it even in ex-USSR countries (like Kazakhstan).
In Swindon, England a similar system was setup in 1928
Early telephone system was used to “broadcast” musical concerts over telephone lines into your home, it wasn’t very popular for lots of reasons, but it was “a thing”…
https://earlyradiohistory.us/1909musi.htm
Soviet radio explained by a former Soviet immigrant
Fwiw
https://youtu.be/xwoNi5UimHk?si=5XbYsc7dhGOljL_s
Here in the U.S. we have a similar system, called [name whatever network you hate].