IAI America IA-T-XD - Manual (Page 103)

Then, press 5 of the ten-key numeric pad several
times to display “n,” and press the return key.
Then, press 1 of the ten-key numeric pad several
times to display “t,” and press the return key.
Pressing the F1 (Alph) key changes the display in
the F1 key field to Num for numeric input.
Enter 5 with the ten-key numeric pad.
Press the return key to confirm the symbol name.
Numeric input
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