Using TrueTTY
With A Screen Reader


   This article is for blind and vision-impaired amateur radio operators who want to convert HF digital mode text from TrueTTY into speech. The other accessibility features of TrueTTY are described in a separate article.

Text to Speech

  Although TrueTTY does not have a built-in speech function, it can be used with any screen reader software. Readers are not designed to work in a text window with streaming characters and scrolling lines, but TrueTTY can transfer decoded text to Windows NotePad, where a screen reader can be used.

   In 2008, W1BLS reported in his blog that he used this feature of TrueTTY to operate with PSK31 and other digital modes.

An Example of a QSO

   Three TrueTTY shortcuts are used:

         CTRL-N copies the received message to a NotePad window.
         ALT-D clears the TrueTTY Received Text Box.
         F12 clears the Transmitted Text Box.

   Two screen reader commands in this example are for JAWS:

1.  Call CQ using a TrueTTY macro.  Shortcut:  F1.
2.  Listen to radio audio for response. Wait for transmission to end.
3.  Copy message to NotePad.  Shortcut:  CTRL-N.
4.  Route JAWS cursor to PC cursor.  INSERT NUMPAD-MINUS.
5.  Read message.  INSERT NUMPAD-DOWN.
6.  Close NotePad without saving.  Shortcuts:  ALT-F4. Then N.
7.  Clear TrueTTY Received Text Box.  Shortcut:  ALT-D.
8.  Clear Transmitted Text Box.  Shortcut:  F12.
9.  Type a reply.

   Selecting "word wrap" in the Notepad Format Menu keeps all the text in an area the word processor can access. This format persists when the computer is restarted.

Automating Keystrokes

   You may also want to use short Windows macro scripts to automate the process. The main advantage is that you can start listening to a message before all of it has been received. A separate article explains how this works and lists the macro scripts.

Sound Card Connections

   Two sound cards are used for digital mode text-to-speech—one for signal processing and one for the speech synthesizer.

   In the TrueTTY Input Sound Card menu (Setup > Interface tab) select the sound card for signal processing (eg, USB audio CODEC). Select the same card in the Output Sound Card menu. For screen reader output:  In Windows Sound Control Panel select the computer primary sound device as the default playback device (eg, Realtek High Definition Audio) so spoken text goes to the PC speaker.

For More Information

PSK31 Operating Notes from a Blind Ham
TrueTTY Accessibility


   Blind and vision-impaired hams can use TrueTTY with a screen reader to hear spoken digital mode text.


  Special thanks to Brian, W1BLS, for his blog about digital modes for blind operators. Thanks also to Kathy, KB1OLH, for adding useful comments to his blog. Sergei, UA9OSV, the author of TrueTTY, answered my questions.


Author Information

   Peter DeNeef, AE7PD, is an Extra Class amateur radio operator in the U.S. This web site has no ads or conflicts of interest.
Email:  HamRadioAndVision "at" gmail "dot" com

rev. 7/28/2012

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