Tektronix SPG8000 Technical Reference page 99

SDI button menu (Option SDI only)
SDI OVERLAY ID TEXT Use this menu to create text or to select a text file that will be overlaid on the
output test signal, and to set the display position of the text.
submenu
NOTE.
You can store overlay functions, including text, in the instrument presets so
that the overlay is restored on power up.
Displaying Text. To display a text overlay, you need to either enter a text string
or create a text file (.txt) and use FTP or a USB memory device to copy the file
to the SDI7/TEXT directory on the instrument. The file must be installed in the
TEXT folder. Files installed in the wrong directory location will be ignored by
the instrument. The instructions for installing custom files are located in the
SPG8000 Quick Start User Manual.
When the string is entered from the front panel, it is limited to 30 characters in
length, and may contain only standard ASCII characters. When a text file is used,
any Unicode character supported by the default font can be displayed. The text
file can be encoded as plain 7-bit ASCII text, or UTF-8 encoding when extended
Unicode characters are used. The text file can also include embedded newline
characters to create text overlays spanning multiple lines.
Font Files. The instrument uses a TrueType font to render text overlays; the
default typeface is Deja Vu Sans. The font file is named "default.ttf" and is stored
in the SDI7 directory of the instrument memory.
The instrument supports Latin, Cryillic, Greek, and symbol character sets for use
with the text overlay. Using FTP, you can download an alternate TrueType font
file. Make sure that the font file is renamed to "default.ttf" and that the instrument
is rebooted for the new font to take effect. The instructions for using FTP or a
USB memory device to install font files are located in the SPG8000 Quick Start
User Manual.
The original Deja Vu Sans file can be recovered from the SPG8000 SW Library
and Documentation CD if necessary.
SPG8000 Technical Reference 87