How to convert Units

This method works with HP49G MODE set RPN
Press [MODE] and [+ / -] if it needs be changed.

Entering unit to convert

Lets convert 142.5 Mph to kph
Type 142.5 in level 1 and Press [ENTER]
Press [UNITS] and go to menu SPEED
Choose Mph
and press the softkey [OK]
It will appears a tagged number
Entering base unit to convert

Type 1 and press [ENTER]
Other time press [UNITS]
and go to menu SPEED
Choose kph
and press the softkey [OK]
Press [UNITS], go to menu TOOLS
and press the softkey [OK]
Choose CONVERT and press [OK]
It will show the result

There is an easier way...

Type 142.5_mph in level 2
type 1_kph in level 1

Note: it is case sensitive.
You need press
for smal case (HP49G default flag).
Press [UNITS], go to menu CONVERT
and press [OK]

And this is the easiest...

With HP49 in RPN mode
Set flag -117 SF
Type -117 SF  [ENTER]

Press   [UNITS]

Type 142.5_mph at level 1
Press and the softkey
closest to kph.