It may seem like an odd concept to younger readers, but there was once a time when people rented their phones rather than buying them outright. Accordingly, these phones were built like tanks, and seeing one of these sturdy classics of midcentury modern design can be a trip down memory lane for some of us. So retrofitting a retro phone with a Raspberry Pi and Google’s AIY seems like a natural project to tackle for nostalgia’s sake.
The phone that [Alasdair Allan] decided to hack was the iconic British desk telephone, the GPO-746, or at least a modern interpretation of the default rental phone from the late 60s through the 70s. But the phone’s looks were more important than its guts, which were stripped away to make room for the Raspberry Pi and Google AIY hat. [Alasdair] originally thought he’d interface the Pi to the rotary dial through DIOs, until he discovered the odd optical interface of the dialer — a mask rotates over a ring of photoresistors, one for each digit, exposing only one to light from an LED illuminated by a microswitch on the finger stop. The digital interface brings up the Google voice assistant, along with some realistic retro phone line sounds. It’s a work in progress, but you can see where [Alasdair] is in the video below.
If stuffing a Google Pi into a retro appliance sounds familiar, it might be this vintage intercom rebuild you have in mind, which [Alasdair] cites as inspiration for his build.
Ten CdS cells! Whodathunkit. Nifty tech, I remember tearing down a similar looking (but beige) phone and the mechanism was quite a bit different.
It’s a modern repo. The only thing it has in common with the original is the case is the same shape. They probably took a mold of it. The plastic finish far from matches the original. Why tho. Reproducing the original mechanical action would not have been too difficult.
Certainly the build quality differs massively too.
I have an original red one. I harvested it from home when BT finally gave us an upgrade to a socket rather than a hard wired phone.
It does duty on the ADSL line in case of some sort of end of the world emergency where only POTS work.
And ringing it from your mobile to scare the bejesus out of anyone stood next to it.
Also managed to find one of those BT tone daillers that some people had back in the day when many phones were still pulse and you wanted to send commands to your answering machine.
Makes dialing a cinch.
Mobiles used to emit the number as DTMF when dialing. Android doesn’t, for security maybe ?
He should put in an easter-egg based on the emergency number from The IT Crowd :)
Too much work.
Too much work to dial it that is.
That’s why it’s perfect for an easter-egg!
What is that button in front of the handset?
IME, it was always a blanking plate on domestic phones, not a button. No idea what circumstances it might be one. Intercom capability in an office environment?
A quick google suggests it’s a “Ringer/Bell On-Off” button.
At least on the phone used in the build it’s a blanking plate. I have a vague recollection from when I was younger that it was a mute button for the ringer. But I could be wrong.
Necro post but, on the original GPO (and maybe BT) rotary dial phones, that was a ‘Party line’ button.
They were common where there was only one telephone line but more than one subscriber, you picked up the handset, listened and if there were no voices on the line, you pushed it to get the dial tone, then you could make a call.
> It may seem like an odd concept to younger readers, but there was once a time when people rented their phones rather than buying them outright.
Pretty sure very few people buy their phones outright these days either. (Although there might be a disproportionally higher percentage among HaD readers). Most people get their phones as lease-to-own from the cellular providers, under horrible contract terms, and with a percentage paid up front.
While this is true, it is understood that you will eventually own the phone if you sign such an agreement. Further, you do actually have the option to purchase your own phone and connect it to a variety of service operators. Back in the day you’d never own the telephone itself (not that it would have been helpful to do so anyway), nor did you have a choice of service operator.
I have several cell phones floating around that I own. They are obsolete, I own them all the same. Around here the total phone and contracts aren’t that horrendous, and are on par with the cost of POTS. You are correct very few purchase the phone outright, unless they are going with a prepay no contract service plan. Even with those the plan subsidizes the lower initial cost of the phone and in the long run one may end up paying full price for the phone, not to mention the plans are in essence not much different than contract. Miss paying one month your service ends.
466453
Oh! I should have thought of that. Doh!
The button was also used on “shared service” lines…
The button was for “party line”
To each their own. To me it’s a table space eating dust collector
To me it would be nice to have back on the end table and wired to the wall.
You might get a kick out of my take :) https://oldestvocation.wordpress.com/2016/08/20/tech-support/