Roland LX-10 Owner's Manual page 39

Example: Playing a Song in the Key of E Major After Transposition to C Major
Hold down the [Transpose] button and press the E key (since E is the tonic).
Counting from C as a reference point, one moves up four keys, including the black keys, to
reach E, thus "+4" appears in the display.
fig.d-Transpose4.eps
fig.Transpose.eps
If you play C E G
If you switch songs or turn off the power, the Transpose setting will return to "0."
#
It will sound E G B
Performing
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