Buried in the user’s manual (PDF) for the iPhone is the following:

Using iPhone with a Teletype (TTY) Machine

Teletype (TTY) machines are used by the hearing impaired to communicate by typing and reading text. If you have the iPhone TTY Adapter cable, available at, you can use iPhone with a TTY machine.

Connect iPhone to a TTY machine

From the Home screen choose Settings → Phone, then turn TTY on. Then connect iPhone to your TTY machine using the adapter cable.

For information about using the TTY machine, see the documentation that came with the machine.

Yes, you can plug in an external TTY and it will work. You need an adapter, typically overpriced for Apple at $19. (I bet it’s a standard jack converter you could get somewhere else.)

I suppose this is halfway decent, but if the iPhone has a TTY mode and a keyboard, why doesn’t it work as a self-contained TTY? (Presumably it uses only the so-called ASCII telecommunications protocol, not the ancient Baudot.) We’ve already got complaints from deaf people about the lack of iChat and captioning.

UPDATE, 2007.07.03: On second thought, I suspect TTY mode at present merely allows passthrough of signals from your external TTY. For the iPhone to transmit TTY tones would require either a software encoder of some kind or a chip that supports the ostensibly standard but actually obscure V.18 specification. I wouldn’t expect either of those before iPhone 2.0, if ever.

The foregoing posting appeared on Joe Clark’s personal Weblog on 2007.07.01 17:00. This presentation was designed for printing and omits components that make sense only onscreen. (If you are seeing this on a screen, then the page stylesheet was not loaded or not loaded properly.) The permanent link is:

(Values you enter are stored and may be published)



This personal Weblog is unlikely to be updated again until my next book comes out. (See Best postings)

Other reading

Topics of interest

Typography ⁓ graphic designTTCCanadian EnglishInversion

Archives by category

Archives by date

Just add /year/month/day/ to the end of site’s URL, You can add just /year/month/, or just /year/, if you wish. Years are four-digit, month and day two-digit (with padding zero below 10). For example:

Copyright © 2004–2021

You enjoy

Transgenderism is to be opposed categorically