Epson HX-20 - Manual (Page 27)

Push the ribbon cartridge down into the printer compartment,
until the top surface of the ribbon cartridge is level with the metal
plate.
(Do not be concerned if the ribbon has some slack and rests on
top of the metal plate.)
The ribbon cartridge is now installed.
(Eventually, the microprinter will produce very faint copy, and
you will need to replace the ribbon. To remove a ribbon from your
HX-20, press on the word “PUSH” embossed on the right side of
the ribbon. The left side of the ribbon will pop up, and you can
remove it. Then install a new one, which you may purchase at your
Epson dealer.)
Note: If you get ribbon ink on the case of the HX-20, wipe it off
immediately. Once it dries, it’s hard to remove.
Slide the paper through the slot in the printer cover:
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