HP LineJet Série Guide De Référence Rapide page 48

Chapter 1
Basic Operating Procedures
17.
Normally, you should not need to adjust the position of the left
tractor.
If adjustment is necessary, unlock the left tractor. Slide the
tractor until it is directly to the left of the number "1" on the
paper scale and lock it. (You can also use the paper scale to
count columns.)
Caution To avoid damage to the printer caused by printing on the
platen, always position the left tractor unit directly to the left
of the "1" mark on the paper scale.
18.
Move the paper supports as necessary to support the paper
through the tractor area.
Paper Scale
Paper Support
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