In Praise of Backward Compatibility


The garden of nerdiness has many flowers: comic book nerds, computer nerds, fantasy nerds, sci-fi nerds–too many to list. After fifty years I’ve finally recognized my own personal nerd category. I’m an electromechanical nerd. This tendency manifests in an obsession with old telephones, the ability to thread a 16mm projector, fantasizing about the mimeographed version of Root Simple and spending evenings watching films about old office equipment. And I have a reverence, bordering on idolatry, for two machines in particular, the Western Electric 500 telephone and the IBM Selectric typewriter. Note that this obsession is not to be confused with Steampunk, despite my past prediction that we’d see the return of the monocle. No, my fantasy world involves a narrow tie, a cocktail in one hand and a heavy phone handset in the other.

I’ve written about it many times before but I’d like to repeat one of the things that I admire most about the Western Electric 500 and mid-20th century telephony in general: the principle of backward compatibility, an idea taken from computer engineering that you can load new software on old machines. Believe it or not, my 45 year old WE 500 still works (more on that below).

Backward compatibility in the case of phones is as much an economic as technical issue. Our phone system used to be a public utility. Before the Bell system was broken up in 1984, the phone company manufactured and maintained all telephones. They were solidly built, made to last and produced domestically by well paid workers. Because it was in their financial interest, the phone company was conservative about changes that would require new equipment. In the entire history of the Bell system, from 1877 to 1984, there were only five different types of circuits.

Once the phone system was broken up we suddenly had many different new telephones to choose from. But it was a false choice. They were all cheap pieces of crap that didn’t last more than a few years. I can’t tell you how many awful cordless telephones I blew through in the 1990s before I went back to my beloved Western Electric 500.

Similarly, we all get to buy new iPhones every other year. Apple is particularly bad about backward compatibility. Like the Bell system, Apple has total control over its hardware and blocks any attempt to go open source. But unlike the the old Bell system, Apple does not have to answer, for the most part, to any regulatory agency. They can turn our perfectly functional iPhone into a doorstop anytime they want and get us to buy a new one.

Maintaining backward compatibility is about deciding on a common sense design vocabulary and sticking to it. While standards can stifle creativity, they can also prevent waste. What if I don’t want to spend hundreds of dollars every two years on a new phone made by underpaid workers?

And what about the way we use phones? Very early on in the history of the phone system certain audio signals were agreed upon: among others these include the dial tone, the ringback tone, the busy signal and the hang up alert. Of these, the one that one rarely hears anymore is the busy signal. Maybe I don’t want to wade through long voice mails or texts. Maybe you just have to wait until I’m off the phone. And the hang up alert (that annoying sound that lets you know an old phone is off the hook) needs to be re-purposed and brought back to prevent so-called “butt dialing” or “pocket dialing.”

But let me end on a hopeful note. During the Christmas holiday, while we were hosting friends and family, AT&T decided to stop servicing my traditional landline/ISDN combo and forced me to switch to their fake fiber optic service called U-Verse (it’s still, for the most part, copper wire based). After I switched, my dial phone stopped working and our internet service degraded so much we were unable to put out this blog without using our cellphones. I called back the friendly AT&T technician who installed U-Verse and he admitted to me that it didn’t work in our neighborhood (thanks for not letting me know that ahead of time!).

In the end I was forced to switch to Time Warner for slightly better and equally expensive service. Our overseas readers should know this is common in the U.S., that we pay a lot of money for poor telecommunications services.

But the electromechanical geek in me had a delightful surprise. Either Time Warner or the folks who designed the modem Time Warner provides had a respect for backward compatibility. Unlike AT&T’s U-Verse service, my Western Electric 500 dial phone still can make an outbound call on Time Warner. The Western Electric 500’s ringer, the bane of Kelly’s existence, still rings. I suspect some old Bell system engineer must be responsible for this obscure technical detail. To that engineer, I lift my cocktail in your honor. May we always hear that electromechanical ring!

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  1. We live on a fairly isolated part of the British Columbia coast with spotty, unreliable cell phone coverage and frequent power outages in winter due to trees falling on the single line and the occasional landslide. In our emergency kit, we keep an elderly Northern Telecom push-button phone, that will work through power outages, cell phone tower failure and almost anything else that Nature can throw at it. It’s as clunky as heck, but looks as though it would work through anything, even submersion.

  2. We still use our Bell wall phone. I think it’s been hanging there for at least 30 years. We don’t do the cell phone thing, heck we didn’t even do the cordless phone thing.I do have a long cord on the wall phone so I can reach the stove and sink when I’m on the phone.

    Disclaimer, my husband worked for Bell Canada, so we have a selection of old phones

  3. I bought the British version of your Western electric after getting thoroughly cheesed off with a selection of crappy cordless phones. It’s from the early 1980’s, it’s tomato red and I love it. A retired telephone engineer rewired it for me (he thought I was bonkers). It doesn’t cope with companies who want you to “press 1 for customer service, press 2 for account enquiries” but it does everything else. and it works when there’s a power cut.

    And I love that we have to explain to visiting children how it works; “So, it’s like, switched on as soon as you pick up the receiver? Cool!!”

    • Funny thing is that, at least here, those “press 1” moments are disappearing and being replaced by voice recognition. And you point out another reason I have an old phone: teasing kids and young adults!

  4. I have an old Bell phone that stopped being able to make outbound calls when we got our new cable/phone service recently. Although I will say that I rarely dialed out on it anymore due to the clunkiness of having to dial all 10 digits on a rotary. But I did like knowing it would still work in a power outage, and I love the ring (the ringer still works and you can still talk on it). My husband can’t claim he didn’t hear the phone ring when I’m out and I try to call him.

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