This worked even while on a call. If you had siblings (or snooping parents), you learned to be alert for the click sound during a call which indicated that someone else had picked up a handset and was now eavesdropping.
When the phone rang, the ring was morse code for the letter matching the intended home. Our number was 4045D, so our ring was long, short, short.
The number of rings determined who the call was for and anyone (even in different houses on the same line) could pick up and listen in or talk on the line.
That last party line in the US was taken out in 1991! https://www.numberbarn.com/blog/phone-history-party-lines/
And there are places elsewhere in the world (for example, some African countries) that skipped completely landlines because mobile phones require much less pervasive infrastructure to work properly.
My mother still uses those rotary phones, BTW. Somehow the telco in her area still supports click-dialing. Incoming calls are great, every damn phone in the house rings simultaneously; sounds like a fire alarm.
I was thrilled that my ISP/Cable company didn't try to sell me their "TV and Phone" bundle because they understood the absurdity or could tell by my voice and interests that I wouldn't be interested or the target audience.
If your phone company was crap, you were kind of stuck, but they usually weren't too bad.
It also worked out because my parents could just call me when it was time for dinner.
ISPs were spottier. I knew some people with T1s paid for with weekend jobs, but some could barely scrape 56k costs.
I also installed the phone line tap in my room myself, so initially I just had to pay for them to come out and turn on the line via the hookup box outside. I think it was like $50 for the initial setup and I saved $100 by running the tap myself.
I also remember dialing a three digit number (maybe 118), and an automated voice would reply with the number you are calling from.
Unlike using multiple telephones, the recipient did not have to be on the line — you could broadcast "Dinner's ready!".
I think I need an intercom as my teen daughters spend all their time up in their rooms....
You are right, cordless phones definitely broadcast with no encryption of any sort. There was a recent HN thread about how radio receivers were banned from receiving the band these phones used because of this.
Especially when building things with impressionable kids, I'd like to encourage people to try to figure out how to build things while minimizing unnecessary third-party dependencies, and secondarily by judicious selection of complexity.
For example, maybe using WiFi and a SoC board with stripped-down Linux, and software to make them talk to each other over the LAN. Or maybe a microcontroller board with a WiFi module in ad-hoc mode. Maybe coded in one of the education-oriented programming tools that the kid will be able to start using soon. Or maybe old-school analog circuits over a pair of copper.
(Or, if you want the kid employable this year, maybe that means gluing together 10 different SaaSes that snoop on your traffic, building a Kubernetes cluster in the cloud for um reasons, using 3 Web frameworks, pulling in 1,000 NPM dependencies, and throwing in half a dozen third-party trackers. :)
No affiliation, just a customer/user.
When something is free it usually is paid for by selling my data, as the free-tier of a paid product, or the owners haven't figured out how to make money on it and are hoping to figure that out later.
Most of the traffic is P2P. We operate a couple of geo distributed relays for NAT'd traffic. But everything is 100% e2e encrypted thanks to webrtc.
It's mostly a tool for us and something that helps sell our other products, but we decided to split it out as a separate app so that it could be used independently. All we collect is a name and email, and even those can be pseudonymous.
Something like WP Super Cache would help a lot during traffic spikes: https://wordpress.org/plugins/wp-super-cache/
I've theorised about such a system myself, though I'd go with live voice-chat through something like a private SIP server (with multiple channels and/or a broadcast mode). With a bit of setup, you could probably integrate Android's native SIP dialer and the various other desktop SIP tools into the system and connect to a channel remotely.
This also means you can do things like turn certain intercoms one-way, or certain ones into priority speaker broadcast mode in software client remotely.
I may not be remembering this correctly, but didn't most mobile phones also have a walkie-talkie feature built-in in the 90's ? I don't think any have that now.
"Nextel's iDEN network offered a then unique push-to-talk "walkie-talkie" feature in addition to direct-dialed voice calls."
The latency (which I never really notice when I'm not also looking at the person talking) made it significantly harder to have a fluid conversation than it should have been.
Made me wonder if something more old fashioned like a walkie-talkie might have been better.
It would be very interesting to port that code. Another option, obviously, is to use a Raspberry Pi instead with pulseaudio and module-echo-cancel enabled.
Both have been entirely superseded by a bunch of Amazon Echo/related devices, which work quite well for that purpose and background music (some rooms I was able to interface with the whole house audio, but overall I wish I had that money and time back).
As we do painting around the house, I remove the intercom panels and patch over the plaster.
For Christmas, my mom decided to get us both a Google Home and a Facebook Portal (with Alexa built in).
We already have an Echo Dot that lives on our fridge that my wife's parents gave us.
Anyway, I thought it was a bit interesting that out of the "big three" evil data stealing tech monopolies, the Google Home was the only one that made me uneasy. I suppose it's a carry over from the whole Firefox / Chrome rivalry.
I don't really care for the Echo Dot we already have, but it is admittedly quite useful for "Hey Alexa, play Christmas music" or "Hey Alexa, set a timer for 10 minutes."
Also I have been legitimately impressed by the video quality and performance of the Facebook Portal because any time I've tried to use their video chat from my computer it's had roughly a 30 second lag and been completely unusable. The Portal is both a crisp picture and no noticeable lag.
I guess the thing I should wonder most about that is why video chat from a traditional computer is so terrible. The only thing I've ever had work decently for video chat with family has been Skype.
It’s remarkable how much of a difference you can make just by skimming off the layers of antiquated crud in a room.
It’s kind of wild to me how often these things are left in place even as they’re retired.
Out of 56 total drop locations (many with multiple cables), we've seen the need to fish new wires down the conduits exactly 0 times in 21 years. That makes for a tough RoI calculation, especially if we'd been paying for all the labor to do the conduit installs.
Whole-home intercom systems were fairly common through the 1970's. I'm not sure why they went out of fashion.
If you're not a tinkerer, and you're in the Apple ecosystem, you can get a HomePod Mini and it will do the coordination so that all of your iOS devices can become one big intercom system, even if you're not at home. Kinda like Nextel used to do.
- kind of ugly and bulky
- fixed in place - you needed to walk over to the panel and push a button to use; but now you're already by the door (where the panels were installed) and can probably just yell faster/easier
- the person you're reaching might have volume turned down, so you resort to yelling anyway
- you might be on the phone or taking a nap and would have to turn down to volume to avoid interruption
- poor speaker/sound quality, so horrible for music playback
- poor build quality and buttons/dials would regularly fail after 5 years or faster if used
- finicky to setup with tons of manual tweaking required to get volume levels where desired
- expensive to repair & proprietary
- expensive to install
However Apple recently introduced an Intercom / Announcement system to their homepods, so we'll try that at some point. I feel like it won't be more than a novelty unless someone knows that I'm in e.g. the garage.
We didn't think much of it at first, but it was actually super useful because going upstairs was relatively inconvenient and shouting didn't work if we were wearing headphones.
Today I guess we would just whatsapp each other.
Presumably much cheaper than HomePod Mini too; I’ve seen the Echo Flex for as low as $10.
Good question. Maybe smaller families and fewer multi-family/multi-generation households?
Yelling was easier than going all the way to the intercom button, but even then it’s not often that you need to communicate with everyone that would justify installing an intercom system.
I like that you were able to assemble it together.
It's a bit like XMPP.
Thanks for building this! (edit: You're a Liverpool fan? I take back what I said... :)
Yes I am! But we are struggling right now so feel pity for me!
EVERY TIME somebody attempts this yet again;
2 oldskool phones and a 9v battery!
thats it, thats the whole thing!
So I never even saw the page this post is about, but somehow I can just feel that it somehow involves an overkill of brand-new digital electronics.
Like; is there a raspberryPI involved? cause I bet theres a RaspberryPI involved.
2 oldskool phones and 1 9v battery. AKA "telecom".
I for one, have created one using Mumble on raspberry, and works even better that OP's solution. I have it running on my computer, and I can mute/unmute with a mouse click. Works for me.
Yes, a RaspberryPI is a "Computer" or "Universal Machine". So literally every ACTUAL SMARTPHONE (regardless of price or ability) is a "Better Solution" than this.
a RaspberryPI for this purpose is such a waste!
"But Think Of The Children!" you cry!?
So now we're teaching the kids that the way to build a house is to buy a skyscraper and burn down the top floors?
Seems like this has been goin on since the "S.T.E.M." fad and its pretty easy to see the effects if you stand back far enough.
you can run a RaspberryPI off a 9v battery too, just not for very long.
Kid: Can I have chocolate chocolate cake for breakfast?
Chatbot: ..."So I give the child a glass of grapefruit juice and chocolate cake --- nutrition. Eggs, milk, and wheat in the chocolate cake"